The Year-book of Facts in Science and Art

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Simpkin, Marshall, and Company, 1848
 

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Página 95 - From these experiments it will appear, that as the temperature rises the light increases in refrangibility ; and making a due allowance for the physiological imperfection of the eye, the true order of the colors is red, orange, yellow, green, blue, indigo, violet. 3. To determine the relation between the brilliancy of the light emitted by a shining body and its temperature. Here we shall find that the intensity of the light increases far more rapidly than the temperature. For example, platinum at...
Página 187 - It is found in irregular shaped bodies, varying in size from that of a pin's head to a pea or small nut, and when seen in its proper sites, has never been found attached to any support whatever. An analysis of the Lecauora shows that there is no fecula in its composition.
Página 144 - Europe, and with heavy orders for agricultural produce, the farmers in the interior of the states of New York, informed of the state of things by the magnetic telegraph, were thronging the streets of Albany with innumerable team-loads of grain almost as quickly after the arrival of the steamer at Boston as the news of that arrival could ordinarily have reached them.
Página 134 - ... they were resting on the wire. Though accidents to the operators, from the direct discharge, may be prevented by the method before mentioned, yet the effect on the machine cannot be entirely obviated ; the residual current which escapes the discharge along the perpendicular wires, must neutralize, for a moment, the current of the battery, and produce irregularity of action in the apparatus. The direct discharge from the cloud on the wire is, comparatively, not a frequent occurrence, while the...
Página 90 - I considered myself justified in announcing "that the quantity of heat capable of increasing the temperature of a Ib. of water by one degree of Fahrenheit's scale is equal to, and may be converted into, a mechanical force capable of raising 838 Ib. to the perpendicular height of one foot"{.
Página 152 - ... estimated. If the sample has been allowed to remain too long in sulphuric acid, the linen threads likewise become brittle, or even eaten away ; if it were not left a sufficient time in it, only a portion of the cotton threads have been removed ; to make this sample useful, it must be washed, dried, and the immersion in the acid repeated. When the tissue under examination consists of pure linen, the portion immersed in the acid likewise becomes transparent, but more slowly and in a uniform manner,...
Página 134 - ... the smaller induced currents may not be felt by the machine. It must be recollected that the inductive influence takes place at a distance through all bodies, conductors and nonconductors; and hence no coating that can be put upon the wire will prevent the formation of induced currents. I think it not improbable, since the earth has been made to act the part of the return conductor, that some means will be discovered for insulating the single wire beneath the surface of the earth; the difficulty...
Página 225 - I think I may safely say, that there can be little if any doubt as to the resolvability of the nebula. — We could plainly see that all about the Trapezium is a mass of stars ; the rest of the nebula also abounding in stars, and exhibiting the characteristics of resolvability strongly marked.
Página 179 - Calebogyne, that male flowers have lately been discovered in New Holland unquestionably of the same species. " Prof. Gasparini, of Naples, has more recently communicated to the scientific meeting held in that city in 1845, his observations and experiments on the cultivated fig, which, though entirely detitute of male flowers, produced seeds having a perfectly developed embryo, independent of fecundation ; access to the pollen of the wild fig, generally supposed to be carried by insects...
Página 62 - ... dried the surface at once. It was then re-dipped, and the process was repeated a dozen times, until the shoe was of sufficient thickness, care being taken to give a greater number of coatings to the bottom. The whole operation from the smearing of the last, to placing the finished shoe in the sun, required less than five minutes. The shoe was now of a slightly more yellowish hue than the liquid milk, but in the course of a few hours, it became of a reddish brown.

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