| Edward Augustus Kendall - Encyclopedias and dictionaries - 1811
...the sun'S rays hito a footn at the distance of 12 inches, the Image will not be ftiore than one tenth **of an inch in diameter, the surface of this little...surface of the lens, and consequently the heat will be** KiOO times greater at the focus than at the lens. Hence the construction of Common burning glasses,... | |
| James Smith - Industrial arts - 1815 - 684 pages
...into a focus at the distance of one foot, the image will not be more than one-tenth of an inch broad. **The surface of this little circle is 1600 times less...than the surface of the lens, and consequently the** density of the sun's rays within it is proportionately increased. It is not therefore Bunting lenses... | |
| Alexander Jamieson - Natural history - 1821 - 448 pages
...into a focus at the distance of one foot, the mage will not be more than one-tenth of an inch broad. **The surface of this little circle is 1600 times less...than the surface of the lens, and consequently, the** sun's rays must be ten times den 324. If the rays of the sun dispersed over the surface of a glass,... | |
| Luke Herbert - Industrial arts - 1825 - 396 pages
...into a focus at the distance of one foot, the image will not be more than one tenth of an inch broad. **The surface of this little circle is 1600 times less...than the surface of the lens, and consequently, the** sun's rays must be ten times denser within that circle ; it is not therefore surprising that it burns... | |
| Sir Richard Phillips - Physics - 1826 - 248 pages
...//IKS. If a lens four inches in diameter collect the sun's rays into a focus at the distance of twelve **inches, the image will not be more than one-tenth...times greater at the focus than at the lens. Cor.** I. Hence the construction of common burning-glasses, which are all double convex lenses. 2. Hence the... | |
| Sir Richard Phillips - Physics - 1826 - 234 pages
...Jllus. If a lens four inches in diameter collect the sun's rays into a focus at the distance of twelve **inches, the image will not be more than one-tenth...diameter, the surface of this little circle is 1600** limes less than the surface of the lens, and consequently the heat will be 1600 times greater at the... | |
| Levi Washburn Leonard - New Hampshire - 1827 - 398 pages
...sun's rays into a focus at the distance of twelve inches, the image will not be more than one tenth **of an inch in diameter : the surface of this little circle is** one thousand six hundred times less than the surface of the lens, and consequently the heat will be... | |
| Levi Washburn Leonard - Science - 1830 - 352 pages
...sun's rays into a focus at the distance of twelve inches, the image will not be more than One tenth **of an inch in diameter : the surface of this little circle is** one thousand six hundred times less than the surface of the lens, and consequently the heat will be... | |
| Leonard Dunnell Gale - Physics - 1838 - 308 pages
...Illustration. If a lens four inches in diameter collect the sun's rays into a focus at the distance of twelve **inches, the image will not be more than onetenth of...1600 times greater at the focus than at the lens.** Corollary 1. Hence the construction of common burning-glasses, which are all double-convex lenses.... | |
| Richard Green Parker - Physics - 1838 - 262 pages
...sun's rays into a focus, at the distance of twelve inches, the image will not be more than one tenth **of an inch in diameter ; the surface of this little...1600 times greater at the focus than at the lens,** t 617. The following effects result from the laws of refraction, stated in No. 593 ; and, first, with... | |
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