166154That the Moon may be a World.
Vertical point.
Or, which is the more eaſie

11Stevinnius

Geog. l. 3.

prop. 3. way, when a man ſhall chooſe ſuch a Station,

where he may at ſome diſtance, diſcern the

place on which the Cloud does caſt its ſhadow,

and withal does obſerve, how much both the

Cloud and the Sun decline from the Vertical

point. From which he may eaſily conclude

the true Altitude of it, as you may more plain-

ly conceive, by this following Diagram.

7[Figure 7]11Stevinnius

Geog. l. 3.

prop. 3. way, when a man ſhall chooſe ſuch a Station,

where he may at ſome diſtance, diſcern the

place on which the Cloud does caſt its ſhadow,

and withal does obſerve, how much both the

Cloud and the Sun decline from the Vertical

point. From which he may eaſily conclude

the true Altitude of it, as you may more plain-

ly conceive, by this following Diagram.

Where A B is a perpendicular from the cloud,

G the Station of him that meaſures, D the place

where the ſhadow of the Cloud doth fall.

G the Station of him that meaſures, D the place

where the ſhadow of the Cloud doth fall.

The inſtrument being directed from the Sta-

tion G, to the Cloud at A, the perpendicular

will ſhew the Angle B A G. Then letting the

Sun ſhine through the ſights of your Inſtru-

ment, the perpendicular of it will give the

Angle B A D. After wards having meaſured

22Pitiſc. Tri-

gon. the diſtance G D by paces, you may, according

to the common Rules, find the height B A.

tion G, to the Cloud at A, the perpendicular

will ſhew the Angle B A G. Then letting the

Sun ſhine through the ſights of your Inſtru-

ment, the perpendicular of it will give the

Angle B A D. After wards having meaſured

22Pitiſc. Tri-

gon. the diſtance G D by paces, you may, according

to the common Rules, find the height B A.

But if without making the Obſervation, you

would know of what Altitude the higheſt of

33Subt. l.

17. theſe are found by Obſervation; Gardan an- ſwers, not above two miles; Keplar, not 44Epit. Co-

per. l. 1. p. 3. 1600 Paces, or thereabouts.

would know of what Altitude the higheſt of

33Subt. l.

17. theſe are found by Obſervation; Gardan an- ſwers, not above two miles; Keplar, not 44Epit. Co-

per. l. 1. p. 3. 1600 Paces, or thereabouts.