An appendix to Clavis horologiæ, or, An explication of the pyramidical dyal set up in His Majesties garden at White-Hall, anno 1669 in which very many sorts of dyals are contained ... / by the Reverend Father Francis Hall, otherwise Line, of the Society of Jesus ...

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Title
An appendix to Clavis horologiæ, or, An explication of the pyramidical dyal set up in His Majesties garden at White-Hall, anno 1669 in which very many sorts of dyals are contained ... / by the Reverend Father Francis Hall, otherwise Line, of the Society of Jesus ...
Author
Line, Francis, 1595-1675.
Publication
[London] :: Printed at Liege, by Guillaume Street, in the year of our Lord 1673, and reprinted at London,
1685.
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Subject terms
Sundials -- Early works to 1800.
Astronomical instruments.
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"An appendix to Clavis horologiæ, or, An explication of the pyramidical dyal set up in His Majesties garden at White-Hall, anno 1669 in which very many sorts of dyals are contained ... / by the Reverend Father Francis Hall, otherwise Line, of the Society of Jesus ..." In the digital collection Early English Books Online 2. https://name.umdl.umich.edu/A44898.0001.001. University of Michigan Library Digital Collections. Accessed June 17, 2024.

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Page 1

AN APPENDIX. A Brief Explication of the Pyramidical Dyal set up in His Majesties Private Garden at White-Hall, July 24. 1669.

THE Dyal being placed upon a Pillar by His Majesties Order in the Privy Garden, it was intimated unto me by divers Worthy Persons as a thing very expedient, that an Explication should be published, of the Use of the several Dyals there contained: For although to divers of them were added a Verse or two, explicating how the Hour, &c. was to be found by them; yet in regard many of them were new, and not to be found in any Author; and others belonging to Astronomy, Cosmography, &c. not so easily conceived by all, they judged very expedient a Declaration thereof should be set forth, whereby such as came dayly to see it, might receive more satisfaction.

Hereupon, having soon after the setting up of the Dyal, left Lon∣don, and being arrived at my Lodging in the Country, I began the said Explication; and being much desirous to add some further Orna∣ment to the Dyal already placed, I began the making of four Water-Dyals, to the placed at the four Corners of the Pyramidical Dyal in a competent distance from the same.

To this Underatking I was moved, as well by the opportunity of a Fountain in the Privy Garden so near the Dyal; as also, for that Ex∣perience

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had taught me, that such Dyals as formerly I had made to shew the Hour in several ways by Water, were for their Rarity and Novelty no less pleasing to the Beholder than the rest.

Being now very busie in these two Employments, and having towards the middle of Winter made a considerable progress therein, I received a Letter from a Friend at London, wherein he told me, that the Dyal, for want of a Cover (which according to His Majesties Gracious Or∣der, should have been set over it in the Winter) was much endamaged by the Snow lying long frozen upon it; and that, unless a Cover were provided (or which we saw little hope) another or two such tempestuous Winters would utterly deface it. Hereupon I laid aside as well the said Explication, as these Water-Dyals, it seeming to no purpose, an Expli∣cation should come forth of the Use of the Dyal, when it was now rendred useless: Which Resolution being understood by some of those worthy Persons, who before had urged for the publishing the said Ex∣plication, they judged, that notwithstanding the Dyal it self should be rendred useless, yet the said Explication was not to be omitted; since thereby would be given occasion to some other skilful Mathemati∣cian (of which we have many in England) to set up another in place thereof, both more specious and durable, and adorned with more variety of Invention.

This Reasonsuting well with the Desire I formerly had of adorning His Majesties Garden with some Curiosity that might in its kind surpass what might elsewhere be found, I resolved to take in hand again the said Explication. Which that it may the better be performed, I will first enumerate the Parts or Pieces of which the whole Dyal consists, and then descend to the Dyals described on each particular Piece.

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CHAP. I. Of the several Parts of this Dyal; and of the Dyals described on each part in general.

THis Dyal standing on a Pillar or Pedestal of Stone, consists chiefly of six Parts or Pieces, one less than another; and pla∣ced one above another in form of a Pyramis, as you see in the Figure.

Of the First Piece.

THE first and largest of these six Pieces, or Base of the said Py∣ramis, is a round Table of about forty inches in Diameter, and some eight or nine inches in Thickness; the Edge whereof is cut into twenty equal Planes, which being made hollow, like so many Boxes of an inch deep, are covered each of them with a clear polish'd Glass, and on the inside of each Glass is described a Dyal; whereof some of them shew the Hour according to the ancient, or Jews manner of counting the Hours; other, according to the counting used by the Babylonians; others, according to the Italians; others according to the way of counting used by Astronomers; and lastly, others shew what Hour it is according to our usual and ordinary way of counting the Hours used in most Parts of Europe. These Twenty Dyals thus described on the Edge of this Table or first Piece, are all vertical declining Dyals; whose Style or Gnomon is either a Lions Paw, or Unicorns Horn, or such like relating to His Majesties Arms, and painted on the bottom of the Box, as shall be said in the next Chapter.

Moreover, upon the upper part of this Table, are placed eight recli∣ning Dyals, all made hollow, and covered with polish'd Glass like the former, but differ chiefly in this, that they shew only the usual Hour in different ways; one of them shewing the Hour by the shade of the Style falling upon the Hour-lines; another by the shade of the Hour∣lines falling upon the Style; a third without any shade either of Hour∣lines or Style, &c.

Upon this Piece stand also four Globes, out into several Panes; up∣on

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one of which Globes are described several Dyals belonging to Geo∣graphy: on another, Dyals belonging to Astronomy, the other Dyals shewing several things appertaining to Astrology; as what Planet reigns every Hour, the Horoscope, Aspects of the Sun with the Stars, &c.

There are also belonging to this Piece, and issuing out of the sides thereof towards the East, West, North and South, four Iron Branches, supposing each of them a Glass-Bowl, which shew the Hour in four different ways, to wit, by the four Elements, as shall hereafter be said.

Of the second Piece.

THE second Piece of the Pyramis is also a round Table, almost like the former, but somewhat less; having only thirty inches in diameter, about the thickness of the first, held up by four iron Sup∣porters. The Edge or Circumference of this Table is cut into six∣teen equal Planes, all made hollow, and covered with Glass, like those of the first Table; but they differ from them in this, that here the Dyals are not described on the Glass Covers, but on the bottom of the Boxes: neither do they shew the Hour, but the different Ri∣sing of the more remarkable Stars, according to the three manners of Risings observed by Astronomers, to wit, the Cosmical Rising, the Acronical, and the Aeliacal, as shall be declared hereafter, when we speak of the Dyals of this second Piece. The Style to each of these Dyals is a little Star painted upon the inside of the Glass-Cover, the better to keep it from the weather.

Out of the sides of this Piece issue also four Branches, towards the East, West, North and South, and carry on each of them a Glass-Bowl to shew the Hour, like those of the first Piece, but in a diffe∣way: for one of them shews the Hour by a Style without a Shadow: another shews it by a Shadow without a Style, &c. whereas those of the first Table shew it by the four Elements, Fire, Water, Air and Earth, as shall be shewed in their due place.

On the upper part of this Table are placed eight reclining Planes; four whereof are covered each of them with a Plate of Looking-glass, on which the Hour-lines, or Style of a Dyal being painted, are re∣flected upon the bottom inclining Planes of the third Piece, and there shew the Hour, as shall be presently demonstrated. The other four have also Dyals upon them, which are to be seen each of them in a

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Looking-Glass placed upon the said bottom inclining Planes of the third Piece; of which we shall now speak.

Of the Third Piece.

THE Third Piece of this Pyramidical Dyal is a great hollow Globe, of about twenty four inches in diameter; and is placed im∣mediately without any Supporter, upon the second piece. The Su∣perficies of this Globe is cut into twenty six Planes; two whereof being Octogones, serve for top and bottom. The rest are divided into eight equal reclining Planes, eight equal inclining Planes, and eight equal vertical or upright Planes. These Planes are all of them made hollow like those of the first and second Piece. The Incliners are not co∣vered with Glass, but left open, that they may the better receive and shew the Dyals reflected, as hath been said, from the second Piece.

Two of the eight upright Planes looking toward the North, have no bottoms, but are covered only with clear Glass, as serving only for windows to look into the Globe, and behold there the Dyals described on the Globe, which are seen as well without the same, as within. The other six have not only each of them a Cover of clear polished Glass, with a Dyal described thereon, like those of the first Piece, but have also a Glass for their bottom; which Glass is thinly painted over with white colour, to the end the shade of the Hour-lines drawn upon the Cover, may be seen as well within the Globe as without. On these bottom-Glasses are drawn several Pictures, holding either a Scepter, or a Troncheon, or the like, the end whereof points the Hour you look for.

Two also of the Recliners looking towards the North, have only a Glass-Cover serving for a window to look into the Globe. The other six have double Glass, like the former: Their Dyals are some drawn upon the Cover, others u••••n the bottom; but all so contrived, that the Hour cannot be known 〈◊〉〈◊〉 them, but only by looking within the Globe.

Moreover, from the top of this Globe issue four iron Branches to∣wards the four parts of the world, each of them carrying a Glass-Bowl, proportionably less than those of the first and second Piece: on which Bowl are also Dyals described, but different from the for∣mer, shewing the Hour according to the several ways of counting the Hours. These Bowls are painted on the inside with thick colour to

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keep out the light, except a little place which is left clear like a Star, for the Sun-beams to pass through and shew the Hour: and the place also where the Hour-lines are drawn, is only painted on the outside thinly with white colour, that the light of the Sun passing through, the said Star may be seen, and shew the Hour.

Of the Fourth Piece.

THE Fourth Piece standing on the aforesaid Globe, and held up by four iron Supporters, like to those which hold up the Second Piece, but proportionably less, is also a round Table of about twenty inches diameter, and six in thickness. The Edge of this Table is cut into twelve equal Superficies, not plain, as hitherto, but concave, as so many concave Semicylinders: on each of which is described a Dyal, which shews the usual Hour by the shade of a Flower-de-luce fixed at the top of each Semicylinder.

From the top of this Table issue forth four iron Branches, carrying each a Glass-Bowl just like those of the first, second and third Piece, though proportionably less. The Dyals described on these Glass-Bowls differ from those of the Third Piece, not because they shew only the usual Hour; but also because here the Hour-lines are all left clear for the Sun-beams to pass through; that by so passing, they may ex∣hibit the like Dyal on the opposite side of the Bowl; which side is for that purpose thinly painted over with white colour, that the said Hours may be seen, and shew the Hour by their passing over a little Star painted in the middle thereof.

Of the Fifth Piece.

THE Fifth Piece standing upon the ••••••rth, and held up also by four iron Supporters, is a Globe of about twelve inches Dia∣meter; whose superficies is cut into fourteen Planes; eight whereof are Triangles equal and equilateral; the other six are equal Squares. The Dyals described on these Planes, shew only the usual Hour by the shade of a Flower-de-luce fastned to the top or bottom of each Plane.

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Of the Last or Highest Piece.

THE Highest Piece or Top of the Pyramis, is a Glass Bowl of some seven inches Diameter, standing upon a Foot of Iron placed on the middle of the Fifth Piece. The North side of this Piece is thin∣ly painted over with white colour, that the shade of a little golden Ball that is placed in the middle of the Bowl, may be seen to pass over the Hour-lines, which are drawn upon the said white colour, and note the Hour. The Bowl is included between two Circles of Iron gilded, with a Cross on the Top.

And thus much concerning the Parts of this Pyramidical Dyal in general.

To which may be added, That the first four Pieces have all their sides covered with little Plates of black Glass, fast cemented to the said Pieces, except those places whereon the Dyals are drawn; which being, as is said, covered also with Plates of polished Glass, there ap∣pears almost nothing on the outside of this Dyal but Glass; which for the greater Ornament of the Dyal, the Angels or Corners where those little Plates of black Glass are joyned together, are gilded as almost all the Iron-work of the Pyramid, as well Supporters, as Branches, Style, &c. are either wholly, or as much as serves for Ornament, covered in like manner with Gold.

CHAP. II. Of the Twenty Vertical Dyals described on the Edge of the first Piece.

BY what is said in the precedent Chapter, of the first Piece, it ap∣pears, that besides the Dyals described on the four great Globes which stand on the said first Piece, there are two and thirty Dyals be∣longing thereto, viz. twenty vertical or upright Dyals, eight reclining Dyals, and four spherical Dyals. Of the twenty verticals we shall now speak in this Chapter, of the eight Recliners in the next; and of the four Spherical in the Fourth Chapter.

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These Verticals being made hollow Boxes (as is said) covered with Glass, the Hour-lines of each of them are drawn upon the Glass; and the Style (which is either a Lions Paw, or Unicorns Horn, &c. is the ordinary way of making Sun Dyals, the shade of the Style or Gno∣mon passes over the hour-lines; here on the contrary, the shade of the hour-lines passes over the Style; so that whereas before, when the Sun did not shine, you saw nothing in the bottom of the Box, but a painted Lion or Unicorn, &c. So now assoon as the Sun shines, you may be∣hold there a perfect Dyal, with all its lineaments and numbers exactly described, and just like the other drawn upon the glass-cover, as being only the shade thereof caused by the Sun-beams passing through the said Glass; which shady Dyal being moved by the motion of the Sun from one part of the said bottom to another, shews by passing over the paw of the Lion; for example, the same hour of the day which in the ordinary Dyal is shewed by the shade of the Style passing over the Hour.

These twenty Dyals thus described, are not all of the same kind, nor shew the time of the day all in the same manner, but in very diffe∣rent ways, according to the different ways of numbring the hours used by several sorts of people; some beginning to count their hours from Sun-rising, others from Sun-setting; others from Noon, others from Midnight. And again, of those who count from Sun-rising, some count always twelve hours from Sun-rising till Sun-setting for the day, and as many from Sun-setting till Sun-rising for the night, whether the days or nights be long or short: And these kind of hours are therefore called the unequal hours, as being longer or shorter, accord∣ing as the days are now longer or shorter. Others there are, who also count from Sun-rising, but continue the number till next Sun-rising; counting always from Sun-rising till Sun-rising twenty four hours; according to which, it is always twenty four of the Clock at Sun-rising. Others on the contrary, count always twenty four hours from Sun-setting till next Sun setting; so that when the Sun sets, it is always twenty four of the clock. Others count always twenty four hours, but begin at Noon, and end at next Noon, and with these it is always twenty four of the Clock at Noon. Lastly, Others begin at Midnight, and count twelve hours till Noon, and then twelve more till Midnight; and accord∣ing to these it is always twelve of the clock at Noon and at Midnight.

The first of these five ways, and which divides the space between Sun-rising and setting into twelve equal parts, making thereby the hours unequal (as is said) that is, longer in Summer than in Winter,

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is the most ancient of all; and are therefore called Horae antiquae. They were anciently used by the Jews, as is manifest by divers places of holy Writ: So that when in St. Matthews, ch. 27. v. 54. it is said to have been darkness (at our Saviours Passion) from the sixth hour to the ninth, it is to be understood according to our manner of reckoning the hours, that there was darkness from Noon till about three of the clock after Dinner: since, according to this counting by unequal hours, it is al∣ways at Noon six of the clock, and twelve at Sun-set. And for this reason they are called here in the Dyal Horae Antiquae sive Judaicae. They are also called Horae Planetariae; because the ancient Astrologers suppo∣sed a new Planet to reign in each of these unequal hours.

The Second Way of counting 24 hours from Sun-rising to Sun-ri∣sing, is used by the Babylonians; and these hours are therefore called Horae Babylonicae, the Babylonian hours.

The Third Way of counting 24 hours from Sun-set to Sun-set, is used chiefly by the Italians; and therefore these hours are called Horae Italicae, the Italian hours.

The Fourth Way of counting also 24 hours from Noon or Mid-day till next Mid-day, is used by Astronomers in calculating the Places and Positions of the Stars and Planets in the Heavens, &c. and are therefore called Horae Astronomicae, Astronomical hours.

The Fifth and last Way, which counts Twelve hours from Midnight to Noon, and as many from Noon to Midnight, is used as well in most parts of Europe, as here in England, and is therefore styled in this Dyal the usual or vulgar way, and the hours Horae Vulgares, the Vulgar or Usual Hours.

Now, there being (as hath been said) Twenty Dyals placed on the edge of this first Piece, there is allotted in the Dyal to each of the five sorts four Dyals, which are so disposed, that at any time of the day you may behold the hour represented in every of them five manner of ways. And that they may be the better understood, I have thought it convenient to set down one of each sort, which by their Titles are easily known.

Page 10

Fig. 1.

For 1. Those Four, whose Title is, Per horas numeratas ab ortu Solis more antiquo, sive Judaico, and have a Red Lion painted on the bottom, shew by the shady Dyal passing over the paw of the Lion what of the Clock it is said to be at White-Hall according to the Ancient, or Jews Account.

Fig. 2.

2. Those Four whose Title is, Per Horas numeratas ab ortu Solis, more Babylonico, and have painted on their bottom a Harp with a Scepter, shew by the shady Dyal passing over the Scepter, what it is of the Clock it is at White-Hall according to the Babylonian way of counting the Hours.

Fig. 3.

3. Those Four whose Title is, Per horas numeratas ab occasu Solis, more Italico, and have on their bottom a Flower-de-Luce, shew by the like shady Dyal passing over the top of the Flower-de-Luce what of the Clock it is there according to the Italian Account.

Fig. 4.

4. Those Four whose Title is Per horas numeratas a Meridie, more Astronomico, and have on their bottom a Unicorn, shew by the often mentioned shady Dyal passing over the tip of his Horn, what of the Clock it is said to be according to the Account used by the Astronomers.

Fig. 5.

5. And Lastly, Those Four, whose Title is, Per horas numeratas a Meridie & media nocte, more usitato, and have on the bottom a Lion painted in its natural Colour, shew by the shady Dyal passing over the Lions paw what of the Clock it is according to the usual and ordinary way of reckoning the Hours.

So that for Example, If at the beginning of July (at what time the Sun rises at Four of the Clock, and sets at Eight) I find, by looking on the usual Dyal that it is just eight of the Clock in the Morning, I shall find at the same time by the Ancient and Judaical Dyal, it is just three

Page 11

of the Clock; by the Babylonian, to be Four; by the Italian Twelve; and by the Astronomical to be Twenty. And thus much for the Use of these Twenty Vertical Dyals.

Now the reason of their difference from the ordinary Dyals, which shew the Hour by the shade of the Style passing over the Hour-lines, is, that the Sun being moved in the same manner, whether the shade of the Hour-lines be moved over the Style, or on the contrary, the shade of the Style moved over the hour-lines, the self same effect, in order to shewing the hour, must needs follow both ways, since the hour-lines are no other than the Sections which the Plains of the hour-circles in the Heavens make with the Plains of the Dyal; in each of which Plains the Style also is as insensibly differing from the Axis of the World.

From whence it follows, that the aforesaid Dyals, being made accord∣ing to the ordinary way of making the like vertical declining Dyals, are to be inverted, to the end they may shew the Hour.

Page 12

CHAP. III. Of the Eight Reclining Dyals standing upon the first Piece.

THE Eight reclining Dyals, being also made hollow, and covered with Glasses like the twenty Verticals we now spoke of, shew only the usual hour, but perform it in different, or rather contrary ways one to another; for of those four which stand upon the fourth part of the Table, one shews the hour by the shade of the Style passing over the hour-lines; another, on the contrary, shews it by the shade of the hour-lines passing over the Style. A third shews it both ways, as well by the shade of the Style passing over the hours, as the shade of the hours passing over the Style. The fourth shews the hour without shade either of Style or hour-lines.

In like manner, of those four which stand on the North-part of the Table; in one you see the hour-lines, but no Style; in another you see the Style, but no hours: In a third you see neither Style nor hours, un∣less the Sun shine, as shall be declared by and by. In the fourth you see both hours and style, but in a different way from what hath been hi∣therto practised; for here you behold the style in the same superficies with the hour-lines; whereas in the common practice of Dyalling, the style is always lifted above the superficies, in which are the hour-lines, to the end it may cast its shade upon them.

And thus much of these eight reclining Dyals in general; we shall now speak of them in particular; and first of those four which stand upon the South part of the Table.

Fig. 6.

The first of these four, whose Title is, Per umbram Styli, and shews (as is said) the hour by the shade of the Style passing over the hour-lines, hath upon the Glass-Cover painted a little Star, which serves for the Style; and on the bottom are drawn the hour-lines, over which the shade of the said Star passing, shews the Hour.

Page 13

Fig. 7.

The Second, whose Title is, Per umbram horarum, and shews the hour by the shade of the hour passing over the style, hath upon the Glass-cover painted a Harp, whose strings are the hour-lines; and on the bottom is painted a Flower-de-luce, whose top serves for the style. So that by the shade of those strings passing over the Flower-de-luce, the hour is known.

Fig. 8.

The Third, whose Title is, Per umbram tam styli quam horarum, and shews the hour as well by the shade of the hours passing over the style, as by the shade of the style passing over the hours, hath upon the glass∣cover an Unicorn painted, with certain little stars on his back; each of which standing for an hour, hath its number written over it▪ on the bottom are drawn the hour-lines of a Dyal, and by them a Scepter; so that when the Sun shines, you may behold the Unicorns shade, being moved by the motion of the Sun, to note the hour with the end of its Horn; and at the same time the shade of the said little Stars to shew the same hour by passing over the Scepter.

Fig. 9.

The fourth and last of these, whose Title is, Sine umbra vel styli vel horarum, and shews the hour without shade of either style or hours, hath painted upon the glass-cover a Flower-de-luce together with a Harp, whose strings are the hour-lines, and the top of the Flower-de-luce is their style. Now out of this Flower-de-luce you shall see when the Sun shines, another Flower-de-luce of Light to arise, and by passing under the said strings of the Harp, to note the hour, and by consequence, to shew (as is said) the hour without shade of style or hours.

As for the reason of the Three first, there needs to add no more than what hath been said of the Twenty Vertical Dyals. But concerning the Fourth, the reason why the Style or Flower-de-luce lies in the same su∣perficies with the hour-lines, is, That the said luminous Flower-de-luce arising out of the painted Flower-de-luce, and shewing the hour, is re∣flected from a Looking-Glass placed upon the bottom of the Dyal.

Page 14

Of the other Four Reclining Dyals which stand upon the North-part of the Table.

THE Three first of these Dyals are so contrived, that the hour cannot be otherwise known by them, than by looking through a little Ring placed on the Back of the Dyal; as shall be now explicated.

Fig. 10.

For in the First, whose Title is, Per horas latentes, If you look on the Face of the Dyal, you perceive no hour-lines, but only a Style, that is, a Flower de-luce painted upon the Cover: And on the contrary, if you look on the back of the Dyal through the said Ring, you shall see the hour-lines, but no style, unless the Sun shine; for then you shall behold the shade of the said Flower-de-luce pass over the said hour-lines, and note the hour.

Fig. 11.

In the Second, whose Title is, Per latentem Stylum, by looking on the Face of the Dyal, you behold only the hours; that is, you see only a Crown bedecked with Stars, each whereof stands for an hour: And on the contrary, by looking on the Back through a little Ring, you be∣hold only the Style, that is, a Scepter, unless the Sun shine; for then you see also the shade of those starry hours pass over the Scepter, and note the Hour.

Fig. 12.

In the Third, whose Title is, Per latentes tam horas quam stylum, you see neither hours nor style by looking on the Dyal; but if you look (as before) on the Back; you may behold the hour-lines; and if the Sun shines, you may perceive also a little Star pass over them, and shew the hour.

Fig. 13.

Lastly, In the Fourth, whose Title is, Per tam stylum quam horas pa∣tentes, there appears both style and hours; but the style is without shade, and the hours without lines; that is, upon the Glass-cover are painted certain little Stars, serving for the hours, and a Scepter, serving for

Page 15

the Style; out of which Scepter, when the Sun shines, you may be∣hold another Scepter of Light to issue, and by passing under the said stars, to shew the hour.

Now for the Reason why in the Three first you cannot see the hour, but by looking through the Ring on the Back of the Dyal, it is, because their Bottoms being Glass thinly painted over with white colour, nothing can be seen by looking on the face of the Dyal, that is drawn on the lower side of the bottom-glass; and on the contrary, by looking on the Back, nothing can be seen that is drawn upon the glass-cover, but only the shade thereof when the Sun shines.

The Reason of the Fourth, is the same which was given for the Fourth of those which stand on the South-part of the Table.

Page 16

CHAP. IV. Of the Four Glass Bowls standing on the Four Branches of the First Piece.

THese Four Bowls shew also the usual Hour in four different ways; for one of them shews the Hour by Fire, another by Water, the Third by the Air, and the Fourth by the Earth; as we shall immediately declare.

Of the First Bowl.

Fig. 14.

THE First therefore, whose Title is, Per Ignem, and shews, as is said, the hour by Fire, is a little Glass-Bowl filled with clear wa∣ter. This Bowl hath about three inches in diameter, and is placed in the middle of another Sphere of about six inches in diameter, consist∣ing of several Iron Rings or Circles, representing the hour-circles in the Heavens. The hour is here known by applying your hand to the said hour-circles when the Sun shines; for that Circle where you feel your hand burnt by the Sun-beams passing through the Bowl filled with wa∣ter, shall shew the true hour; according to the Latine Verse there ad∣joyned.

Cratem tange, manuf{que} horam tibi reddet adusta.

The Reason of this Dyal is, that the parallell'd Rays of the Sun pas∣sing through the said little Bowl, are bended by the density of the water, into a Cone or Pyramis, whose vertex reaches a little beyond those hour-circles, and there burns the hand applied; for so many Rays being all united into a Point, must needs make an intense heat, which heat is so powerful in the Summer-time, that it will fire a piece of Wood ap∣plied unto it.

Page 17

Of the Second Bowl.

Fig. 15.

THE Second Bowl, whose Title is, Per Aquam, shews the Hour by Water, that is, by the Rays of the Sun passing through the water with which the Bowl is filled, as in the precedent; which Rays, although they be bended by the density of the water, as before, yet they burn not, being cut off at their going out of the Bowl, by a little white colour laid thin on that part where they break out; making thereby only a round Circle of Light upon the said Co∣lour; the Center of which Circle shews the Hour amongst the Hour-Circles there described on the said white Colour; as the Latine Verse doth also explicate:

Luminis hoc Centrum qui tangit, tangit & horam.

The Reason of this Dyal (besides what we now said of the bending of the Rays, is, that these hour-circles being no other than the Secti∣ons which the Planes of the Celestial hour-circles crossing each other in the Center of the Bowl, make in the superficies thereof, and the said Center of the Circle of Light made on the Bowl, answering perpetu∣ally to the Center of the Sun, it necessarily follows, that it shews always the true hour, as any one that knows but the first Principles of Dyal∣ling, will conceive.

Of the Third Bowl.

Fig. 16.

THE Third Bowl, whose Title is, Per Aerem, and shews the hour without any style, is only filled with Air, and exhibits to the sight, when the Sun shines, two little Pictures of the Sun, like two small Stars within the Bowl, both which, if by moving your Eye, you bring under the same hour-circles described on the Bowl, or at least, parallel unto it, they shall shew the true hours, according to the Latine Verse there under-written.

Ʋnam det geminus Sol horam, & vera patebit.

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Now the reason why by those little Pictures of the Sun seen both un∣der the same hour-circle, or parallel to it, you find the hour, is, that those hour-circles described on the Bowl, being the Sections which the Planes of the Celestial Hour-Circles make in the superficies of the Bowl, (as was said also of the second Bowl) and these two little Suns being reflected one of them from the convex superficies of the Bowl, and the other from the concave, it follows by the Rules of reflection, that those two Pictures of the Sun are both seen in the same Plane; in which is also the Eye which seeth, and the Sun which is seen. Wherefore since the Sun is always in the Plane of the true Hour-circle, it necessarily follows that the Eye beholds both those Pictures at the true hour; for although one reflection cannot sufficiently determine the Eye to behold the Sun in the true hour-circle, yet two reflections suffice.

Where is also to be noted, that these three Bowls we have now spoke of, have this preheminence above all other Dyals depending on the shade of the style, that they shew the hour, when by none of the others it can be discerned; that is, when the Sun shines so dimly that it casts no perceptible shadow.

Of the Fourth Bowl.

Fig. 17.

THE Fourth Bowl, whose Title is, Per Terram, shews what of the Clock it is in any part of the World, which is here performed by a Geographical Description of the whole Earth upon the inward super∣ficies of the Bowl, together with a Meridian-circle moveable upon the North and South Poles, and the Equinoctial circle divided into its 24 equal hours, and fastned to the said Meridian, at the hour of Twelve; at which place also is erected a Flower-de-luce, and at the North-Pole is fastned a Thred. The Bowl being thus prepared, and rightly placed, if you turn the said moveable Meridian till the Flower-de-luce cast no shade upon the Bowl, and then bringing the Thred over any part of the World till it cross the Equinoctial-circle, you shall see the hour there noted belonging to that part or parts of the World over which the said Thred passed; according to the Verse there adjoyned.

Ʋmbram tolle Orbi, totum{que} stat Hora per Orbem.

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CHAP. V. Of the Four great Globes standing on the First Piece.

Of the First Globe.

THE First therefore of these Globes, whose Title is, Horologia Geographica, having about Thirteen inches in diameter, hath its superficies cut into thirty two Planes; whereof twenty are Triangles all equal and equilateral; the other twelve are Pen∣tagones, or five angled Figures, all of them likewise equal one to ano∣ther. Some of these Pentagones are made hollow like Hemispheres, others like Cones, the rest, as also the Triangles, are left plain. The Dyals described as well on the Pentagones, as on the Triangles, have for style, a sharp-pointed Iron perpendicularly erected.

The Dyals described on the Pentagones, shew not only the situation of the more remarkable Countries in the World, but also what several actions are performed in them at the same time; for example, who are now at Dinner, who at Supper, who are rising, who sleeping, &c.

Fig. 18.

For those two whose Title is, Tempus surgendi, shew by the shade of the style in what part of the World it is time of rising, or six of the Clock in the Morning.

Fig. 19.

Those, whose Title is, Tempus Prandendi, shew in the same manner, in what part of the World it is time of Dining or Mid-day.

Fig. 20.

Those, whose Title is, Tempus Coenandi, shew in what Countrey it is Supper-time, or six of the Clock at Night.

Fig. 21.

Those, whose Title is, Tempus Dormiendi, shew where it is Midnight, or time of sleeping.

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Fig. 22.

But those two, whose Title is, Habentes Solem supra Caput, shew by the shade of the style what People, whether by Sea or Land, have the Sun just over their Heads at such a time as you look upon the Dyal; which is performed by inverting that part of the Terrestrial Gobe which is included between the two Tropicks.

The Reason of which inversion is, that the shade of the style being always cast towards the contrary part to the Sun, that is, if the Sun be East, the shade falls towards the West, &c. it was necessary the Eastern part of the World should here lie Westwards, and the Northern South∣wards. And thus much for the twelve Pentagones described on the Globe.

Fig. 23, & 24.

Now for the twenty equilateral Triangles; the Dyals described on them, shew only what of the clock it is in this or that particular place, according to the usual way of counting the hours from Midnight to Noon, and from Noon to Midnight; whereof only three Examples are here set down thus; one of these Dyals shews what of the Clock it is at Jerusalem, another at Constantinople, another in Jamaica, &c.

Of the Second Globe.

THE Second Globe, whose Title is, Horologium Astronomicum osten∣dens, &c. is just like the former, whereof we have now spoken; that is, the superficies thereof is cut into twelve Pentagones, and twenty Triangles; but the Dyals described on these Pentagones and Triangles, are much different from those of the former, as not only shewing the hour of the day, but divers other things belonging to Astronomy, as, the Azimuth, or distance of the Sun from the South, the Almicanta∣rath, or height of the Sun above the Horizon, what hour he rises and sets; and the like; of which are now to treat.

Fig. 25.

1. The Dyal, whose Title is, Azimuth Solis a Meridie, shews by the shade of the style (which in each Dyal here also is perpendicularly

Page 21

erected) how many degrees the Sun is distant from the true South, at such time as you look upon the Dyal: The Lineaments of this Dyal are no other than the Sections which the Plains of the vertical Circles crossing each other, on the top of the style, make with the superficies of the Dyal.

Fig. 26.

2. The Dyal, whose Title is, Altitudo Solis supra Horizontem, shews how many degrees the Sun is elevated above the Horizon. The Linea∣ments of this Dyal are the Sections which the superficies of the Dyal makes with those cones whose bases are parallel to the Horizon, and whose common vertex is the top of the style, or center of the Earth.

Fig. 27.

3. The Dyal, whose Title is, Incipit Aurora, shews at what hour be∣gins Break of Day, that is, when first the Crepusculine Arch begins to appear. The Lineaments by which this is here performed, are the Sections which the superficies of the Dyal makes with the cones, whose bases are parallel to the Equator, and whose common vertex is the top of the style, or the Earths Center.

Fig. 28.

4. The Dyal, whose Title is, Sol oritur, shews by the now named Sections of those Cones whose bases are parallel to the Equator at what hour the Sun riseth, and by consequence when he sets.

Fig. 29, & 30.

5. The Dyal, which hath for Title, In quo Signo Zodaici sit Sol, shews by the said Sections of the superficies of the Dyal with the Cones, whose bases are parallel to the Equator, in what part or sign of the Zodiack the Sun is; but because the shade of the top of the style falls twice every year upon the same Section, by reason of the Suns ascending and de∣scending from the one Tropick to the other: therefore to avoid confu∣sion, there are two Dyals of the same sort, one serving from the 10th. of December to the 10th. of June; the other from the 10th of June to the 10th. of December.

Page 22

Fig. 31, 32.

6. The Dyal, whose Title is, Dies Mensis, shews by the like conical Sections now mentioned, what day of the Month it is; at least, as near as can be expected in so little a form. Here are likewise two Dyals of the same sort, for the reason now mentioned. And these Dyals within this second Globe we have hitherto spoken of, are all of them described on the Pentagones: Those which follow, are described on the Trian∣gles.

Fig. 33.

7. The Dyal, whose Title is, In qua parte Horizontis incipiat Aurora, shews in what part of the Horizon begins the Break of Day, that is, in what part thereof begins first to appear the convex part of the Crepuscu∣line Arch; whether just in the East, or in the North-East, or South-East, &c. and by consequence, in what part also the Evening Twilight ends. The Lineaments of this Dyal are the Sections which the Planes of the vertical Circles crossing each other on the top of the style, make with the plane of the Dyal.

Fig. 34.

8. The Dyal, whose Title is, Duratio Crepusculi, shews by the now often mentioned conical Sections of the superficies of the Dyal with the Cones, whose bases are parallel to the Equator, how long as well the Morning as Evening Twilight doth last, that is, how many hours are from Break of Day till Sun-rising; and from Sun-set∣ting to the end of Twilight, or till dark night.

Fig. 35.

9. The Dyal, whose Title is, In qua Coeli plaga existat Sol, shews by the Sections of the vertical Circles, See Num. 7. in what part of the Heaven the Sun is, whether in the East or West, South-East, or South-West, &c.

Fig. 36.

10. The Dyal, whose Title is, Amplitudo ortiva Solis, shews by the conical Sections mentioned in num. 3. how many degrees the Sun rises wide of the true East-point, whether towards the North, or towards the South.

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Fig. 37.

11. The Dyal, whose Title is, Quot horae restent ad occasum Solis, shews by the Sections of the Italian (c. 2. n. 3.) hour-Circles with the superficies of the Dyal, how many hours rest till Sun-set.

Fig. 38.

12. The Dyal, whose Title is, Quota pars Diei sit elapsa; shews by the sections of the unequal (as n. 3.) hour-circles, what part of the day, or space from Sun-rising to Sun-setting is now spent, whether the Third, or Fourth, or Fifth, &c.

Fig. 39.

13. The Dyal, whose Title is, Declinatio Solis, shews by the coni∣cal sections mentioned n. 3. the Suns declination, that is, how many de∣grees he is distant from the Equator.

Fig. 40.

14. The Dyal, whose Title is, Qua hora Sol perveniat ad verum Ori∣entem, shews by the same conical sections, at what hour the Sun comes to be just East, and by consequence, at what hour after Dinner it will be just West.

Fig. 41.

15. The Dyal, whose Title is, Refractio Solis, shews by the conical sections, spoken of n. 2. the Suns Refraction, that is, how many mi∣nutes he appears to be elevated above his true height, by the bending of his Rays in passing through our thick Atmosphere.

Fig. 42.

16. The Dyal, whose Title is, Quoties umbra contineat corpus erectum, shews by the shade of the style falling upon the aforesaid conical secti∣ons mentioned in n. 2. how often the shadow of a Body perpendicu∣larly erected upon a Plain parallel to the Horizon, contains the length of the same Body.

Page 24

Fig. 43.

17. The Dyal, whose Title is, Longitudo Diei, shew by the shade of the style falling upon the conical sections spoken of, n. 3. the length of the day, that is, how many hours are between Sun-rising and setting.

Fig. 44.

Lastly, The Dyal, whose Title is, Quot sint horae elapsae ab ortu Solis, shews, by the shade of the Style falling upon the sections which are made in the superficies of the Dyal, by the Plains of those circles which divide all the parallels of the Suns dayly motion into twenty four equal parts, according to what was said, c. 2. n. 2. how many hours have passed since Suns-rising.

Of the Third Globe.

THE Third Globe, whose Title is, Horologium Ʋranographicum, is about the same bigness with the two former; but the superficies thereof cut into twenty Triangles, all equall and equilateral, some where∣of are made hollow like Cones, the rest left plain. The Dyals de∣scribed on these Triangles, shew what situation or posture the Heavens have at any time of the day, when the Sun shineth, that is, what stars are rising, what setting, what stand just over your head, &c. So this Globe standing immoveable, performs, by the shade of the styles be∣longing to these several Dyals, that in effect, which a Celestial Globe, whereon all the fixed stars or constellations are painted, would do, if being rightly placed, it were continually turned about, according to the Suns dayly motion: where is to be noted, that here are always two Dyals of each sort, one serving one half year, and the other an∣other, for the reason given in the Fifth Dyal of the Second Globe.

Fig. 45, 46.

1. Therefore, Those two Dyals, whose Title is, Constellationes Ori∣entes, shew by the shade of the style, what Constellation or Company of stars begin then to arise above the Horizon, provided that you look upon the Dyal belonging to the time of the year which you are now in,

Page 25

according to what was now said. The lineaments of these Dyals are the Sections which the Plain of the Ecliptick Circle makes with the super∣ficies of the Dyals at such time as those several Constellations noted upon the Dyal, begin to rise.

2. Those two, whose Title is, Constellationes Occidentes, shew in like manner what Constellation begins to set, or go under the Horizon. The Lineaments of these two Dyals are the Sections which the Plain of the Ecliptick Circle makes with the superficies of the Dyal at such time as this or that Constellation begins to set.

3. Those two Dyals, whose Title is, Constellationes existentes in Me∣ridie, shew what Constellation begins to pass the Meridian Circle, or full South, which is here performed by the sections which the Plain of the Ecliptick Circle makes with the superficies of the Dyal, when the several Constellations there noted, begin to pass the Meridian Circle.

4. Those two whose Title is, Constellationes existentes in ipso Oriente. shew what Constellations stand just East, whether it be in the Horizon, or elevated above the same, which they perform by those Sections which the Plain of the Ecliptick makes with the Plain of the Dyal, when such Constellations as are there noted, do pass the East Circle, or first Vertical.

5. Those two, whose Title is, Constellationes existentes in ipso Occi∣dente, shew on the contrary what Constellations stand just West, which is done by the like Sections made by the Ecliptick, when those Con∣stellations begin to pass the true West.

6. Those two Dyals, whose Title is, Constellationes existentes supra Caput, shew what Constellation stands over your head; which is also done by the aforesaid Sections made when the Constellations there no∣ted, pass the Zenith, or vertical Point.

Now these twelve Dyals being all made (as is said) by the Sections of the Ecliptick with the superficies of the Dyal, it will be sufficient to give here a Diagram of the two first.

But because these two Dyals shew only what situation the stars have in the day-time, when the stars cannot be seen, unless there should happen a total Eclipse of the Sun, there are therefore described on the same Globe six other Dyals, shewing what situation the stars will have at 8 of the Clock at Night; a time proper to behold them; and see the truth of the Dyal.

Page 26

Fig. 47, 48.

7. Those two Dyals, whose Title is, Constellationes existentes in Ori∣ente hora octava vespertina, shews what Constellation will stand just East∣ward at Eight of the Clock at Night; which is here performed by the Sections which the superficies of the Dyal makes with those Cones whose bases are parallel to the Equator, and whose common Vertex is the top of the style, or Center of the Earth.

8. Those two, whose Title is, Constellationes existentes in Occidente hora octava vespertina, shew by the fore-named Sections, what Constel∣lations will be just Westward at Eight of the Clock in the Evening.

Lastly, Those two, whose Title is, Constellationes existentes in Meri∣die hora octava vespertina, shew by the Sections which their superficies make with their aforesaid Cones, what Constellation at Eight of the Clock at Night will be just South.

And these six Dyals being made by the Sections of the same Cones, it will suffice to place here the Diagram of the two first: And thus much of the Third Globe,

Of the Fourth Globe.

Fig. 49.

THE Fourth and last Globe, whose Title is Horologium Astronomi∣cum, is also cut into twenty Triangles, equal and equilateral, just like the Precedent.

The Dyals described on these Triangles, belong to Astrology, and are placed here for those who are delighted with such conjectural Un∣certainties. These Dyals are as follow.

1. The Dyals, whose Title is, Domus Astrologica Solis, shews in which of the twelve Astrological Houses, described according to the way of Regiomontanus, the Sun is at the time you behold the Dyal. The Li∣neaments of this Dyal are the Sections which the plains of those Cir∣cles, which crossing each other on the North and South Points of the Horizon, divide the Equator into 12 equal parts, beginning at the East point of the Horizon, and so descending, make with the Plain of the Dyal.

Page 27

Fig. 50, 51.

2. Those two Dyals, whose Title is, Signum horoscopans, shew the Horoscopon (as Astrologers term it) that is, which of the twelve Signs do begin to rise above the Horizon; which is here performed by the Sections which the Plain of the Ecliptick makes at the time they begin to rise, with the superficies of the Dyal.

3. Those, whose Title is, Signum culminans, shew by the like Secti∣ons of the Ecliptick with the superficies of the Dyal, what Sign of the Zodiack is in the Meridian, or full South. Wherefore these four Dyals being made by the same sections, it suffices also to put a Diagram only of the two first.

Fig. 52.

4. Those Dyals which serve here for the several days of the week, shew what Planet reigns, according to the Opinion of ancient Astrolo∣gers, every hour of the day: So the Dyal, whose Title is, Dominatur die Lunae, shews what Planet reigns any time of the day on Monday.

Fig. 53.

And in the same manner, the Dyal, whose Title is, Dominatur die Martis, shews what Planet reigns at any time on Tuesday. And so of the rest. The Lineaments of these Dyals being all alike, to wit, the sections which the plains of the unequal hour-circles make with the super∣ficies of the Dyal, it will be sufficient also to put here the Diagrams of the two first.

Fig. 54, 55.

5. Those two Dyals, whose Title is, Conjunctio Solis cum Stellis fixis, shew with which of the more remarkable fixed Stars the Sun is in con∣junction, or under the same Circle of Longitude.

Lastly, Those two, whose Title is, Varit Aspectus Solis cum Stellis fixis, shew the other Aspects of the Sun; as the Trine-Aspect, the Quadrat, &c. with the said fixed stars. These four Dyals being made much alike, as made by the sections which the superficies of the Dyal makes with the cones whose bases are parallel to the Equator, and com∣mon Vertex, is the top of the style, or center of the Earth, it will suf∣fice to place here also the Diagram of the two first. And thus much of the Dyals belonging to the first Piece.

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CHAP. VI. Of the Dyals described on the Edge of the Second Piece.

Fig. 56, 57.

1. THose Dyals which are described on the Edge of this Table, have for Title, Stellae Orientes Cosmice, shew what Stars rose cosmically (that is to say) rose at the same time when the Sun rose, on the day you look upon the Dyal; provided you look upon the Dyal belonging to the time of the Year, here being two Dyals of the same sort, one for the one half of the Year, and another for the other half.

2. Those Dyals, whose Title is, Stellae Orientes Acronice, shew what Star will rise acronically, that is, will rise just at Sun-setting; where also Care is to be had, that you look upon the Dyal agreeable to the time of the Year.

Lastly, Those Dyals, whose Title is, Stellae Orientes Heliace, shew what Stars rise that day Heliacally, that is, what Star, which for some time before, had, by reason of its nearness to the Sun, lay hid, begins now to appear again, by getting out of the Sun-beams.

Now the Lineaments of these Dyals, being all of the same sort, to wit, such conical sections as the Plain of the Dyal makes with the Cones, whose Bases are parallel to the Equator, and whose common Vertex is at the top of the style, that is, at the middle of the little painted Star, which here in each Dyal represents the Style: This, I say, being so, it will suffice here to place two Diagrams of the first sort.

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CHAP. VII. Of the Eight Reflecting Dyals placed on the Top of the Second Table.

THE Reason why these Dyals placed upon the second Table were made by reflexion of Looking-Glasses, was not so much for variety, as for necessity; for the Table standing high, the Dyals placed on the upper part thereof, could not have been seen, but by being reflected on the bottom or inclining Plains of the great Globe, which stands (as is said in the first Chapter) upon this second Table; whereas, now being reflected, they are very well seen upon the said-bottom, together with their Titles, as followeth:

Fig. 58.

1. The Dyal, whose Title is, Per horas sine stylo, hath its hour-lines described, and visible on the bottom of the aforesaid Globe, but by the style, which is a Flower-de-luce, being painted upon a Looking-Glass placed on the Table, appears not, but only the shadow thereof appears; which being reflected upon the said hour-lines, drawn on the bottom of the Globe, shews the hour, according to the Verse there adjoyned:

En-Horas! stylus a lucenti Sole petendus.

These hour-lines being no other than the sections which the Plains of the ordinary hour-circles, crossing each other upon the top of the said Flower-de-luce, make with the Plain of the Dyal, no more needs to be said but that it is a reflex Dyal, supposing always the Sun as much depressed under the Horizon, as it is de facto elevated above it.

2. The Dyal, whose Title on the contary, is, Per stylum sine horis, hath its style (which is a Lions Paw) painted upon the bottom of the Globe, and therefore easie to be seen; but the hour-lines being drawn upon a Looking-Glass placed upon the Table, appear not, only their shadow reflected upon the said Lions Paw, shew the hour, according to what the Verse there intimates;

Da mihi Phoebe horas, horam{que} tibi ungue notabo.

This Dyal being only the former invers'd, according to what was said of the like inversion in the second Chapter, there needs no more to be

Page 30

added: As also neither is it needful to say any more of the other, which there in the self-same manner shews the hour by the hour-lines reflected upon the end of an Unicorns Horn; according to the Verse;

Sol mihi Luce dat horas, horam do tibi Cornu.

3. In the Dyal, whose Title is, Sine Horis vel Stylo, appears neither hour-lines nor Style, unless the Sun shine; for then you see them both; that is, you see the shadow of both style and hour-lines reflected from the Looking-Glass, upon which the said Hour-lines are drawn.

This Dyal differing nothing from an ordinary reclining Dyal decli∣ning, we need say no more thereof; as neither of the other four, which also differ no otherwise from ordinary Dyals, than that they are not to be otherwise seen than each of them in a Looking-Glass placed on the bottom of the great Globe. Wherefore it will suffice to place the Dia∣grams of the two first.

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CHAP. VIII. Of the Four Dyals supported by the Four Branches of the Second Piece.

THese Four Dyals are drawn each of them upon a Glass-Bowl of a∣bout five Inches diameter, and shew the usual hours by four dif∣ferent ways, viz. by a shade, without any style, by a style without any shade, by a style and shade, and without either style or shade.

Fig. 60.

1. The Dyal, whose Title is, Per stylum sine umbra, shews the hour by moving the style (which here is a Flower-de-luce fixed on a move∣able Equator) to and fro till it cast no shade upon the Bowl; which be∣ing done, the hour sought for shall stand just under the style; as the Verse there added declares:

Nulla sit umbra stylo; veram stylus indicat horam.

Now the Reason, why the style casting no shade on the Bowl, stands over the true hour, is, that these hours lying all in the sections, which the Plains of the hour-circles make in the superficies of the Bowl, it is necessary that then the top of the style be in the Plain of the same hour-circle, in which at that time is also the Center of the Sun.

Fig. 61.

2. In the Dyal, whose Title is, Per umbram sine stylo, the hour is found by observing where the part of the Bowl enlightned by the Sun, meets with the part not enlightned; for this meeting shews the hour, as the there adjoyned Verse explicates:

Vis horam? lucem{que} inter tenebras require.

The Reason whereof is, That the Sun, by reason of its immense di∣stance enlightning without any considerable difference, the one half of the Bowl, and the hour-points being all noted in the Equator of the Cone or Sections which the Plain of the Equator passing through the Center of the Bowl, makes in the superficies thereof, the said termina∣tion

Page 32

of Light must needs fall upon the true hour-point, provided that the Dyal be once rightly placed.

Fig. 62.

3. The Dyal, whose Title is, Per Stylum & Ʋmbram, shews the hour by the shade of a style perpendicularly erected upon the superficies of the Bowl, and therefore differs nothing from an ordinary Dyal descri∣bed on the convex superficies of a Globe. There are three such Dyals placed upon this Bowl, to the end that when the shade of the style ceases, by reason of the convexity of the Bowl, to shew the hour in one, may shew it in another.

Fig. 63.

Lastly, The Dyal, whose Title is, Sine Stylo vel Ʋmbra, shews the Hour without either style or shadow; for if you place your self, so as to behold your face in the middle of the little convex Looking-Glass which is there placed on the South-pole of the Bowl, you shall at the same time, if the Sun shine, behold the Picture thereof at the true Hour; according to the Verse there adjoyned.

Spectanti Speculum Horam dat tibi Solis Imago.

The Reason whereof is, that the Eye, when placed, as is said, being in the Axis of the World, and by consequence, in the Plain of all the hour-circles, and therefore in the Plain of the true hour-circles, in which Plain also, the center of the Sun being necessarily placed, it fol∣lows that the said Picture of the Sun appears at the true hour, since by the Rules of Reflexion, the Eye seeing, and the Point seen, are in the same Plain with the Point of the Reflextion.

As for the Hour-lines of these four Dyals, they are no other than the Sections, or some point of them, which the Plains of the hour-circles make in the superficies of the Bowls; which Plains in the first, second, and fourth, cross each other in the Center of the Bowl; but in the third, they cross one another at the top of the Style.

Page 33

CHAP. IX. Of the Dyals described on the great Globe which stands on the Second Table.

THis Globe having Eight reclining Plains, eight inclining, and Eight upright Plains, the Dyals described on them, are as followeth; 1. Six of the Eight upright Plains being made hollow, like those Twenty on the edge of the first Table, are covered also with Glass, and Dyals described on them, just like those twenty; the difference only being, that here the bottoms are also covered with Glasses thinly painted over with white colour, to the end the Dyals may be seen as well with∣in the Globe, as without: To which purpose, two of these upright Plains, looking towards the North, are covered only with clear Glass, as serving for Windows to look into the Globe. On the said Bottom-Glasses are drawn several Pictures; as of their Majesties, the Queen Mother, the Duke of York, Prince Rupert, &c. In His Majesties Picture the Hour is shew'd by the shade of the Hour-lines passing over the top of the Scepter. In the Pictures of the two Queens, it is shew'd by the like shade passing over the top of a Flower; and in the other three, by passing over the end of a Troncheon, which each of them hold in their hands; under each Picture is written a Chronograph for the Year 1669. in which Year the Dyal was set up; and futable to the Person.

Which Chronographs, according to the Order now named, are as followeth:

  • 1. Regnet DiV CarolVs IMperetqVe BritannIs
  • 2. FaXIt Regina Det Regi RegnoqVe ProLem CatharIna,
  • 3. RegIna Mater nato sIbI Carolo DIV frVatVr.
  • 4. IaCobVs & RegIs frater, & InsignIs BrItanniae aDMIraLIVs,
  • 5. FILIVs SeCVnDVs RegIs BoheMIae.

Page 34

These six Vertical Dyals being all alike, it will suffice to place here the Diagrams of the two first.

Fig. 64, 65.

As for the Dyals described on the reclining Plains of this Globe, they are in substance like those Recliners placed upon the first Table, except that, whereas those of the first are most of them made to shew the hour by looking on the outside of the Dyal, here no hour can be seen but by looking through the aforesaid Windows into the Globe; which doing, you shall behold in one a Star, in another a Flower-de∣luce, shewing the hour, by passing over the hour-lines; in a third, you shall behold a Lion, with certain Stars on his back, each whereof repre∣sents an hour, to pass under a Cloud, and so by successively hiding them, to note the hour; and the like of the rest of these Recliners. As for the reclining Plains, which are placed on the bottom of the Globe: the Dyals belonging thereto, are already explicated in the precedent Chapter, as made by reflection of Looking-Glasses, &c.

Page 35

CHAP. X. Of the Four Glass-Bowls supported by the Four Branches of the Great Globe.

OUT of the top of the great Globe issue (as was said in the first Chapter) four Branches, each bearing a Glass-Bowl, like those of the first and second Piece, but somewhat less in proportion to the Pyramis. These four Bowls are gilded over, except where the Hour-lines are drawn, which is thinly painted over with white colour, to the end the Sun-beams passing through a little Star left clear on the top of the Bowl, and making the like Star of Light upon the hour-lines, may be seen to note the hour.

These Dyals shew the hour according to the different ways of num∣bring the hours, used by several Nations, as was said in the second Chapter.

Fig. 66.

1. The Dyal, whose Title is, Per horas Italicas, shews by the said luminous Star passing over the hour-lines, what hour it is to be said ac∣cording to the Italian Account, which numbers from Sun-set to Sun-set 24 hours. These hour-lines are the Sections which the Plains of the Italian hour-circles crossing each other in the middle of the said Star placed on the top of the Bowl, make in the superficies thereof.

Fig. 67.

2. The Dyals, whose Title is, Per horas Babylonicas, shews in like manner, what hour it is according to the Babylonians way of reckoning, who count 24 hours from Sun-rising till next Sun-rising, which it per∣forms by the sections which the Plains of the Babylonian hour-circles crossing each other in the middle of the said Star, make in the superfi∣cies of the Bowl.

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Fig. 68.

3. The Dyal, whose Title is, Per Horas Astronomicas, shews by the like Star, the hour according to the Astronomical Account, which numbers 24 hours from Noon till next Noon. This Dyal is made by the like sections of the usual hour-circles crossing each other in the mid∣dle of the said Star; the Numbers set to the hours being only different, that is, One of the Clock in the Morning is here called Thirteen, and Two Fourteen, and Three Fifteen, &c.

Fig. 69.

Lastly, The Dyal, whose Title is, Per Horas antiquas, sive Judaicas, shews the Hour according to the ancient way of numbring the hours, viz. counting always 12 Hours from Sun-rising till the setting thereof: Wherefore the sections by which this Dyal is made, are those which the Plains of the unequal hour-circles make in the superficies of the Bowl; which Plains also cross each other in the middle of the Star, or Style of the Dyal.

And thus much of the Third Piece, with the Branches belonging to it. The Diagrams belonging to these Four Bowls are as follow∣eth:

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CHAP. XI. Of the Three uppermost Pieces of the Pyramis.

THE Dyals belonging to the three lower Pieces of the Pyramis, being explicated in the precedent Chapters, we will now in this Chapter explicate the rest, that is to say, the Dyals appertaining to the Three highest, or uppermost parts thereof.

Fig. 70.

The Fourth Piece therefore, consisting (it is said in the first Chap∣ter) of twelve concave Semi-Cylinders, and standing upon the great Globe, held up by four Supporters, like those which hold up the second Piece, but less, hath upon each of those Semi-Cylinders a Dyal descri∣bed, shewing the usual hour by the shade of a Flower-de-luce fixed at the top of a Semi-Cylinder.

Out of the top of this Piece issue four Branches, carrying each a lit∣tle Glass Bowl, shewing also the usual hour by the Light of the Sun penetrating through the hour-lines (which for that purpose are left trans∣parent, the rest of the Bowl being gilded over) and passing over a little Star painted on the lower part of the Bowl.

Fig. 71.

The first Piece, consisting of 8 plain Triangles, equal and equilateral, and six equal squares, and held up also by four Supporters, hath in like manner Dyals described thereon, shewing the usual hour by the shade also of a Flower-de-luce.

Fig. 72.

The Sixth and last Piece, or top of the Pyramis, is a great Glass-Bowl standing upon the Fifth, supported by a Foot of Iron, and en∣compassed with two Iron Circles, having on the Top a Cross. This Bowl also shews the usual hour by the shade of a little Golden Ball placed in the middle of the Glass.

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The Dyals belonging to these three Pieces, shewing only (as is said) the usual hour, it will suffice to set down a Diagram for each Piece.

As for the Reason of these Dyals, they all shewing only the usual hour, there needs no more to be said than what hath been already of the like, viz. that in the Fourth and Fifth Pieces, the Plains of the Hour-circles cross each other upon the top of the Flower-de-luce; but in the Sixth, they cross on the Center of the little Ball placed in the middle of the great Bowl.

The Dyals of the four little Bowls supported by the Branches, are no other than the Astronomical Dyal of the precedent Chapter, inverted, and only differ in the Numbers set to the Hours.

And thus much concerning what in this short Tract was intended to wit, the Use and Reasons of the Dyals described on the said Py∣ramis.

FINIS
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