Ure's Dictionary of Arts, Manufactures, and Mines: Containing a Clear Exposition of Their Principles and Practice

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Longman, Green, Longman, and Roberts, 1860
 

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الصفحة 218 - All these things being considered, it seems probable to me that God in the beginning formed matter in solid, massy, hard, impenetrable, moveable particles, of such sizes and figures, and with such other properties and in such proportion to space as most conduced to the end for which he formed them; and that these primitive particles being solids are incomparably harder than any porous bodies compounded of them, even so very hard as never to wear or break in pieces, no ordinary power being able to...
الصفحة 218 - And therefore that nature may be lasting, the changes of corporeal things are to be placed only in the various separations and new associations and motions of these permanent particles...
الصفحة 219 - Chemical analysis and synthesis go no further than to the separation of particles one from another, and to their reunion. No new creation or destruction of matter is within the reach of chemical agency.
الصفحة 219 - In all chemical investigations. it has justly been considered an important object to ascertain the relative weights of the simples which constitute a compound. But unfortunately the enquiry has terminated here; whereas from the relative weights in the mass, the relative weights of the ultimate particles or atoms of the bodies might have been inferred, from which their number and weight in various other compounds would appear, in order to assist and to guide future investigations, and to correct their...
الصفحة 219 - We might as well attempt to introduce a new planet into the solar system, or to annihilate one already in existence, as to create or destroy a particle of hydrogen.
الصفحة 353 - ... than it would have been by beating ; and the compression is so much greater, that a rolled book will be reduced to about five-sixths of the thickness of the same book if beaten. A shelf, therefore, that will hold fifty books bound in the usual...
الصفحة 219 - If there are two bodies, A and B, which are disposed to combine, the following is the order in which the combinations may take place, beginning with the most simple, namely: 1 atom of A + 1 atom of B = 1 atom of C, binary. 1 atom of A + 2 atoms of B = 1 atom of D, ternary.
الصفحة 219 - The following general rules may be adopted as guides in all our investigations respecting chemical synthesis. 1st. When only one combination of two bodies can be obtained, it must be presumed to be a binary one, unless some cause appear to the contrary.
الصفحة 17 - Scientific definitions, whether they are definitions of scientific terms, or of common terms used in a scientific sense, are almost always of the kind last spoken of : their main purpose is to serve as the landmarks of scientific classification. And since the classifications in any science are continually modified as scientific knowledge advances, the definition! in the sciences are also constantly varying.
الصفحة 483 - The face of the block is either carved in relief into the desired design, like an ordinary woodcut, or the figure is formed by the insertion edgewise into the wood of narrow slips of flattened copper wire.

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