# An Easy Grammar of Natural and Experimental Philosophy: For the Use of Schools

Kimber & Conrad; W. Brown, printer, 1811 - Celestial mechanics - 152 pages

### Popular passages

Page 2 - Co. of the said district, have deposited in this office the title of a book, the right whereof they claim as proprietors, in the words following, to wit : " Tadeuskund, the Last King of the Lenape. An Historical Tale." In conformity to the Act of the Congress of the United States...
Page 65 - ... and, consequently, the heat at the focus is to the common heat of the sun, as the area of the glass is to the area of the focus. Thus, 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...
Page 28 - ... them. Here the power must exceed the weight in the same proportion as the distance of the weight from the prop exceeds the distance of the power.
Page 70 - And if he hold out his hand towards the mirror, the hand of the image will come out towards his hand, and coincide with it, of an equal bulk, when his hand is in the centre of concavity; and he will imagine he may shake hands with his image.
Page 63 - If the medium which the rays enter be denser, they move through it in a direction nearer to the perpendicular drawn to its surface. On the contrary, when light passes out of a denser into a rarer medium, it moves in a direction farther from the perpendicular. This refraction is greater or less — that is, the rays are more or less bent, or turned aside from their course — as the second medium through which they pass is more or less dense than the first. To prove this in a satisfactory...
Page 19 - UB, be drawn parallel to them, so as to complete the parallelogram, then the line which the body A will describe will be in the diagonal AD, and the length of this line will represent the force with which the body will move.
Page 54 - That upon very great winds, though they be not accompanied with rain, the mercury sinks lowest of all, with relation to the point of the compass the wind blows upon.
Page 81 - C to all parts of the glass, and each plane surface will refract these rays to the eye, the same object will appear to the eye, in the direction of the rays which enter it through each surface. Thus, a ray...
Page 43 - The pressure of a fluid upon any given part of the bottom or sides of a vessel is equal to the weight of a column of that fluid, having a base equal to that part of the bottom or side, and an altitude equal to the perpendicular height of the fluid above it.
Page 23 - If a line be drawn from the centre of gravity of a body perpendicular to the horizon, it is called the line of direction, because it is the line that the centre of gravity would describe if the body fell freely.