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 ...

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

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

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

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.

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.