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Page 45 - In calm weather when the air is inclined to rain, the mercury is commonly low. In serene settled weather the mercury is generally high. During very great winds, though unaccompanied with rain, the mercury sinks lowest of all with relation to the point of the compass from which the wind blows.
Page 61 - 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 35 - 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 96 - If there were a hundred persons so situated, they would every one feel the shock at the same instant. The electric fluid may be thus conveyed many miles in a moment of time.
Page 67 - It is made by placing a convex glass in a hole of a window shutter, and if no light enters the room but through the glass, the pictures of all objects on the outside may be distinctly seen in an inverted position, on any white surface placed at the focus of the lens.
Page 107 - ... the card may not be disturbed by the wind. What is called the card, is a circular piece of paper, which is fastened upon the needle, and moves with it.
Page 11 - 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 63 - Thus, the pencil of rays qrs, that flows from the point A of the object, will be converged to the point a on the retina; those from the point B will be converged to the point b ; those from the point C will be converged to the point c ; and so of all the intermediate points ; by which means the whole image...
Page 57 - F, of the convex glass def, some of the rays which flow from every point of the object, on the side next the glass, will fall upon it, and after passing through it, they will be converged into as many points on the opposite side of the glass, where the image of every point will be formed, and consequently the image of the whole object, which will be inverted. Thus the rays...