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Сторінка 104 - Tait 2 used this expression in a Rede Lecture delivered at Cambridge : " It seems as if iron becomes, as it were, a different metal on being raised above a certain temperature ; this may possibly have some connection with the ferricum and ferrosum of the chemists.
Сторінка 85 - Thus, it is possible to appreciate the effect of small quantities of metallic impurity as affecting the colour resulting from the action of the pickle. Copper containing a small quantity of antimony gives a shade very different from that resulting from the pickling of pure copper. But the copper produced in Japan is often the result of smelting complex ores, and the methods of purification are not so perfectly understood as in the West. The result is that the socalled
Сторінка 282 - What people call applied science is nothing but the application of pure science to particular classes of problems. It consists of deductions from those general principles, established by reasoning and observation, which constitute pure science. No one can safely make these deductions until he has a firm grasp of the principles ; and he can obtain that grasp only by personal experience of the operations of observation and of reasoning on which they are founded.
Сторінка 115 - F.) is almost a viscous fluid," and he considers that glass-hard steel is constantly being spontaneously " tempered " at the ordinary temperature, which, he says, " acting on freshly quenched [that is, hardened] steel for a period of years, produces a diminution of hardness about equal to that of 100° C. (212° F.), acting for a period of hours.
Сторінка 37 - Riemsdijk,2 of Utrecht, has observed that a globule of gold or silver, in a fused state, will pass below its solidifying point without actually solidifying, but the slightest touch with a metallic point will cause the metal to solidify, and the consequent release of its latent heat of fusion is sufficient to raise the globule to the melting point again, as i» indicated by a brilliant glow which the button emits, a beautiful effect which I hope to show you.
Сторінка 74 - Graham's palladium ; and allotropic nickel. It was further shown that metals could be obtained in chemically active states under the following conditions : — Joule proved that when iron is released from its amalgam by distilling away the mercury the metallic iron takes fire on exposure to air, and is therefore clearly different from ordinary iron, and is, in fact, an allotropic form of iron.
Сторінка 35 - ... and is now undergoing an investigation by Dr. Andrews, which may be expected to throw much light upon its nature ; (2.) the colloidal condition or constitution, which intervenes between the liquid and crystalline states, extending into both, and affecting probably all kinds of solid and liquid matter in a greater or less degree.
Сторінка 103 - ... and he adds the expression of the belief " that the excellence of the latter metal might be tested by ascertaining the amount of change in thermo-electric condition which can be produced by the process of hardening.
Сторінка 86 - V section, в, and hammer the mass until the holes disappear ; the holes will thus be replaced by banded circles and the trenches by banded lines. A Japanese artificer taught me to produce similar effects by taking the soldered layers of the alloy, and by the aid of blunted tools making depressions on the back of the mass so as to produce prominences on the front, c. These prominences are filed down until the sheet is again flat ; the banded alloys will then appear on the surface in complicated sections,...
Сторінка 84 - In the case of the shaku-do, we shall see presently the gold appears to enable the metal to receive a beautiful rich purple coat or patina, as it is called, when treated with certain pickling solutions ; while shibu-ichi possesses a peculiar silvergray tint of its own, which, under ordinary atmospheric influences, becomes very beautiful, and to which the Japanese artists are very partial. These are the principal alloys, but there are several varieties of them, as well as combinations of shaku-do...