This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1888 Excerpt: ...is admitted above the piston and escapes below. In the lefthand figure it is again for the instant closing both pas sages. The slide-valve is in constant motion up and down, being driven by a kind of crank (called an eccentric) which revolves with the fly-wheel. Very often the feet of the slide-valve are lengthened, as ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1888 Excerpt: ...is admitted above the piston and escapes below. In the lefthand figure it is again for the instant closing both pas sages. The slide-valve is in constant motion up and down, being driven by a kind of crank (called an eccentric) which revolves with the fly-wheel. Very often the feet of the slide-valve are lengthened, as in fig. 86, so as LIGHT. Chapter XIV. RECTILINEAR PROPAGATION. PLANE MIRRORS. 162. Light is known to us through our sense of sight. The things which we see send light to our eyes, and it is by means of the light so sent that we see them. Some bodies allow light to come through them, and are called transparent; others prevent it from passing, and are called opaque. An opaque body hides from us any object which lies upon the production of a straight line drawn from our eye to the opaque body. On the other hand, when we see an object through a hole in an opaque obstacle, the object so seen lies upon the production of a straight line drawn from our eye to the hole. It is thus proved that light travels in straight lines. A line along which light travels is called a ray, and the name is also applied in a loose sense to the light which travels along the line. As a lane has no breadth, every point of a visible object must be regarded as sending out an infinite number of rays in different directions. When we want to speak of all the rays which a point of an object sends to the pupil of an observer's eye, or to the object-glass of a telescope, or to any other surface of finite size, we call them, a pencil of rays. They form a solid cone or pyramid from whose vertex they all proceed. 163. The fact that light travels in straight lines is conspicuously shown by a beam of sunshine coming 1ML Bensetuw.--When a rav of light, as SL tig. 90. fails on a plane m...
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Add this copy of Elementary Text-Book of Physics to cart. $24.30, new condition, Sold by Ebooksweb rated 3.0 out of 5 stars, ships from Bensalem, PA, UNITED STATES, published 2010 by Nabu Press.
Add this copy of Elementary Text-Book of Physics to cart. $110.68, like new condition, Sold by Ebooksweb rated 3.0 out of 5 stars, ships from Bensalem, PA, UNITED STATES, published 2010 by Nabu Press.
Add this copy of Elementary Text-Book of Physics to cart. $110.68, very good condition, Sold by Ebooksweb rated 3.0 out of 5 stars, ships from Bensalem, PA, UNITED STATES, published 2010 by Nabu Press.
