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Page 135 - From the foregoing statements it may be safely inferred that " the mean height of the barometer at the level of the sea being the same in every part of the globe...
Page 152 - For this purpose, circular and horizontal indentations are cut out quite around it, and at proper distances, according to the thickness to be given to the millstones. Wedges of willow, dried in an oven, are then driven into the indentations, by means of a mallet. When the wedges have sunk to a proper depth, they are moistened, or exposed to the humidity of the night, and next morning the different pieces are found separated from each other. Such is the process which, according to M. de Mairan, is...
Page 350 - ... sides, forming a multitude of ramifications heaped one upon the other, which will sometimes pass over the edge of the vessel, and extend themselves on the outside, with all the appearance of a plant.
Page 120 - Pont-Royal, when at its mean height, is 400 feet broad, and 5 deep. When the river is in this state, the velocity of the water is estimated at 100 feet per minute, taking a mean between the velocity at the surface, and that at the bottom. If the product of 400 feet in breadth, by...
Page 217 - ... a hazel, of different sizes and strength, only they were forked branches, and hazel was preferred, as forking more equally than most other trees ; but it is not requisite that the angle should be of any particular number of degrees. He held the ends of the twigs between each fore finger and thumb, with the vertex pointing downwards. Standing where there was no water, the baguette remained motionless; walking gradually to the spot where the spring was under...
Page 217 - A la Baguette. This account was received with unbelief, almost amounting to derision. The Marquis, piqued at being discredited, sent for the man, and requested we would witness the experiment. A large party of French and English accordingly attended. The man was quite a peasant in manners and appearance : he produced some twigs cut from a hazel, of different sizes and strength, only they were forked branches, and hazel was preferred, as forking more equally than most other trees ; but it is not requisite...
Page 121 - But a considerable part of this water, perhaps three fourths, immediately runs off: so that no more than 405000 forces its way through the earth and sandy soil, till it meets with a bed of clay at the depth of two or three feet, from which it flows to the mouth of the fountain, and feeds it. If...
Page 53 - ... will have a very sensible motion; so that the moveable extremity of the small bar cannot pass over the hundredth or thousandth part of a line, without a point of the circumference of the last wheel passing over several inches. If this circumference then have teeth fitted into a pinion, to which an index is attached, this index will make several revolutions, when the dilatation of the bar amounts only to a quantity altogether insensible.
Page 68 - ODOURS. — It is said that a grain of musk is capable of perfuming for several years a chamber twelve feet square without sustaining any sensible diminution of its volume or its weight. But such a chamber contains 2,985,984 cubic inches, and each cubic inch contains 1,000 cubic tenths of inches, making in all nearly three billions of cubic tenths of an inch. Now it is probable, indeed almost...
Page 353 - To melt Iron in a Moment and make it run into Drops. BRING a bar of iron to a white heat, and then apply to it a roll of sulphur. The iron will immediately melt, and run into drops. This experiment should be performed over a basin of water, in which the drops that fall down will be quenched.