Popular cyclopaedia of natural science (by W.B. Carpenter).

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Pagina 114 - Every body must persevere in its state of rest, or of uniform motion in a straight line, unless it be compelled to change that state by forces impressed upon it.
Pagina 114 - Inertia is that property of a body by virtue of which it tends to continue in the state of rest or motion in which it may be placed, until acted on by some force.
Pagina 219 - An account of experiments for determining the length of the pendulum vibrating seconds in the latitude of London.
Pagina 8 - The change of a solid into a liquid is usually termed its melting, fusion, or liquefaction; whilst the change from the liquid to the gaseous state is called vaporization, — when made rapidly, boiling, — or if made slowly, evaporation.
Pagina 55 - The property of receiving a new set by the blow of a hammer, or by impact, as it is properly termed, is called malleability. As there is a great difference in the ductility of different metals, so also there is in their malleability. In general, the most ductile metals are also the most malleable ; but there is a remarkable exception in the case of platinum and iron. Platinum and iron are more ductile than copper, zinc, tin, and lead ; but copper and tin are more malleable than platinum ; and even...
Pagina 268 - Fi ?- 149 when the tooth A comes into contact with B, it acts obliquely upon it, and as it moves, the corner of B slides upon the plane surface of A in such a manner as to produce much friction, and to grind away the side of A, and the end of B. As they approach the position CD, they sustain a jolt the moment their surfaces come into full contact; and after passing the position...
Pagina 53 - ... or l-30th of an inch, a bundle containing the same quantity of material will sustain a weight of from 60 to 90 tons. For the sake of comparison it may be mentioned that a mass of hemp fibres glued together will sustain a weight of 41 tons per square inch ; whilst copper wire will not sustain more than...
Pagina 227 - ... that the power is to the weight, as the distance of the weight is to the distance of the power. Thus, suppose that we have a piece...
Pagina 306 - Without friction, it would be impossible to make a roj>e of the fibres of hemp, or a sheet of the fibres of flax ; neither could the short fibres of cotton have ever been made into such an infinite variety of forms as they have received from the hands of ingenious workmen. Wool also has been converted into a thousand textures for comfort or for luxury ; and all these are constituted of fibres united by friction. In fine, if friction retards the motion of machines, and consumes a large quantity of...
Pagina 43 - In the manufacture of embroidery it is necessary to obtain very fine gilt silver threads. To accomplish this, a cylindrical bar of silver, weighing 360 ounces, is covered with about two ounces of gold. This gilt bar is then wire-drawn, as in the first example, until it is reduced to a thread so fine that 34-00 feet of it weigh less than an ounce. The wire is then flattened by passing it between rollers under a severe pressure, a process which increases its length, so that about...

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