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according acid action animals appear applied atmosphere become body called carbonate cause centre cold color common consequence considerable considered consists containing continued covered crystals described direction dissolved distance earth effect equal experiments fall feet fire fixed flowers force four give given glass greater half heat inches iron kind known leaves length less light lime liquid machine manner matter means metal miles minute mixed motion move nature nearly necessary object observed obtained operation ounces passing piece pipe placed plants plate portion position prepared present produced proportion quantity rays remain round salt seen separated side similar solution steam string substance sufficient sulphuric supposed surface taken temperature tion tube turned vessel weight wheel whole wire wood
第 301 頁 - These are usually accounted six in number, viz. the Lever, the Wheel and Axle, the Pulley, the Inclined Plane, the Wedge, and the Screw.
第 97 頁 - ... the needle, the graver, the spring of a watch or of a carriage, the chisel, the chain, the anchor, the compass, the cannon, and the bomb. It is a medicine of much virtue, and the only metal friendly to the human frame.
第 268 頁 - Laches was repeated as before, and a new tree was launched in a similar manner. By these means a tree descended every five or six minutes, provided no accident happened to the slide, which sometimes took place, but which was instantly repaired when it did.
第 117 頁 - But the author prefers to make the copies upon photographic paper prepared in the way which he originally described in a memoir read to the Royal Society, in February 1839, and which is made by washing the best writing paper, first with a weak solution of common salt, and next with a solution of nitrate of silver. Although it takes a much longer time to obtain a copy upon this paper, yet when obtained, the tints appear more harmonious and pleasing to the eye ; it requires in general from three minutes...
第 116 頁 - Make a saturated solution of crystallized gallic acid in cold distilled water. The quantity dissolved is very small. Call this solution B.
第 105 頁 - His method is as follows: The salt to be crystallized is to be dissolved in water, and evaporated to such a consistency that it shall crystallize on cooling. Set it by, and when quite cold pour the liquid part off the mass of crystals, at the bottom, and put it into a flat-bottomed vessel. Solitary crystals form at some distance from each other, and these may be observed gradually increasing.
第 287 頁 - ... into the next room ; and with so great ease and geometrical symmetry, that, though it work day and night, from one end of the year to the other, it will not require forty shillings reparation to the whole engine, nor hinder one day's work.
第 381 頁 - ... That the strata are very nearly regularly disposed around the centre of gravity of the earth. — 3. That the surface of this spheroid, of which the sea covers a part, has a figure a little different from what it would assume in virtue of the laws of equilibrium, if it became fluid. — 4. That the depth of the sea is a small fraction of the difference of the two axes of the earth. — 5. That the irregularities of the earth, and the causes which disturb its surface, have very little depth.—...
第 161 頁 - Take antimony, calcine it with a continued protracted heat, in a flat unglazed vessel, adding to it from time to time a sufficient quantity of any animal oil or salt, dephlegmated ; then boil it in melted nitre for a considerable time, and separate the powder from the nitre by dissolving it in water.