Mathematicall recreations. Or, A collection of many problemes, extracted out of the ancient and modern philosophers as secrets and experiments in arithmetick, geometry, cosmographie, horologiographie, astronomie, navigation, musick, opticks, architecture, statick, mechanicks, chemistry, water-works, fire-works, &c. Not vulgarly manifest till now. Written first in Greeke and Latin, lately compi'ld in French, by Henry Van Etten, and now in English, with the examinations and augmentations of divers modern mathematicians whereunto is added the description and use of the generall horologicall ring: and the double horizontall diall. Invented and written by William Oughtred.

2. Secondly, how much is the depth of the earth, the height of the heavens, and the compasse of the world?

FRom the surface of the earth unto the Cen∣tre according to ancient traditions, is 3436. miles, so the vvhole thicknesse is 6872 miles,

of which the whole compasse or circuit of the earth is 21600 miles.

From the Centre of the earth to the Moone there is neare 56 Semidiameters of the earth, which is about 192416 miles. unto the Sunne there is 1142 Semidiameters of the earth, that is in miles 3924912; from the starry firma∣ment to the Centre of the earth there is 14000 Semidiameters, that is, 48184000 miles, accord∣ing to the opinion and observation of that learned Ticho Brahe.

From these measures one may collect by A∣rithmeticall supputations, many pleasant pro∣positions in this manner.

First, if you imagine there were a hole through the earth, and that a Milstone should be let fall down into this hole, and to move a mile in each minute of time, it would be more than two dayes and a halfe before it would come to the Centre, and being there it would hang in the aire.

Secondly, if a man should go every day 20 miles, it would be three yeares wanting but a fortnight, before he could go once about the earth; and if a Bird should fly round about it in two dayes, then must the motion be 450 miles in an houre.

Thirdly, the Moone runnes a greater com∣passe each houre, than if in the same time she should runne twice rhe Circumference of the whole earth.

Fourthly, admit it be supposed that one

should go 20 miles in ascending towards the heavens every day, he should be above 15 years before he could attaine to the Orbe of the Moone.

Fifthly, the Sunne makes a greater way in one day than the Moone doth in 20 dayes, be∣cause that the Orbe of the Sunnes circumfe∣rence is at the least 20 times greater than the Orbe of the Moone.

Sixthly, if a Milstone should descend from the p••ace of the Sunne a thousand miles every houre, (which is above 15 miles in a minute, farre beyond the proportion of motion) it would be above 163 dayes before it would fall dovvne to the earth.

Seventhly, the Sunne in his proper sphere moves more than seven thousand five hundred and seventy miles in one minute of time: novv there is no Bullet of a Cannon, Arrovv, Thun∣derbolt, or tempest of vvinde that moves vvith such quicknesse.

Eightly, it is of a farre higher nature to con∣sider the exceeding and unmoveable quicknesse of the starry firmament, for a starre being in the Aequator, (which is just between the Poles of the world) makes 12598666 miles in one houre which is two hundred nine thousand nine hun∣dred and seventy foure miles in one minute of time: & if a Horseman should ride every day 40 miles, he could not ride such a compasse in a thousand yeares as the starry firmament moves in one houre, which is more than if one

should move about the earth a thousand times in one houre, and quicker than possible thought can be imagined: and if a starre should flye in the aire about the earth with such a prodigious quicknesse, it would burne and consume all the world here below. Behold therefore how time passeth, and death hasteth on: this made Coper∣nicus, not unadvisedly to attribute this motion of Primum mobile to the earth, and not to the starry firmament; for it is beyond humane sense to apprehend or conceive the rapture and vio∣lence of that motion being quicker than thought; and the word of God testifieth that the Lord made all things in number, measure, weight, and time.