Proceedings of the American Academy of Arts and Sciences, Volym 17Metcalf and Company, 1882 Vol. 12 (from May 1876 to May 1877) includes: Researches in telephony / by A. Graham Bell. |
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Proceedings of the American Academy of Arts and Sciences, Volym 42 American Academy of Arts and Sciences Obegränsad förhandsgranskning - 1907 |
Proceedings of the American Academy of Arts and Sciences, Volym 43 American Academy of Arts and Sciences Obegränsad förhandsgranskning - 1908 |
Proceedings of the American Academy of Arts and Sciences, Volym 41 American Academy of Arts and Sciences Obegränsad förhandsgranskning - 1906 |
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AgBr air-dried salt lost akenes anal analyses angles antimony argentic Arizona arsenic atomic weight baric barium base BaSO Benth boiling Boston bracteis bracts bromide Calculated calyx carbonate caudal chloride chromatophores Coahuila colors corolla crystals cultivated curcumin deflection determinations dibromacrylic acid dissolved dorsal electromotive force ether flowers foliis formula glabrous grammes Gray H₂O H₂SO heat herbarium Hort hydrate hydrobromic acid ignition inches long involucre leaves Lemmon length lines long Linnæan Linnæus lobes lobis melting molybdic Mountains Muhl nearly Nuevo Leon Nutt obtained P₂O Parry & Palmer pedicels Peltier effect phospho-molybdates phosphoric oxide pigment plant Plate potassic precipitate pubescent rays salt gave Saltillo San Luis Potosi San Miguelito Schaffner sepals silver slender soluble solution species specimen stage stem substance gave sulphuric acid Sutherland Springs temperature Texas thermo-electric current thermometer Torr tube ventrals Willd yellow
Populära avsnitt
Sida 395 - It can now be asserted upon convincing evidence that savagery preceded barbarism in all the tribes of mankind, as barbarism is known to have preceded civilization.
Sida 420 - The proof of this great generalization, like that of all other generalizations, lies mamly in the fact that the evidence in its favor is continually augmenting, while that against it is continually diminishing, as the progress of science reveals to us more and more the workings of the universe.
Sida 30 - Add to the sulphuric acid one part of the water and cool the mixture. Then dissolve the potassium bromide in six parts of the water by means of heat, supplying the loss of water by evaporation during the heating. Pour the diluted sulphuric acid slowly into the hot solution with constant stirring, and set the mixture aside for twenty-four hours, that the sulphate of potassium may crystallize.
Sida 39 - Let -IT and ir1 denote the heat — measured in dynamical equivalents — absorbed and evolved at the hot and cold junctions respectively in unit time by unit current. Let E be the electromotive force of a battery, maintaining a current / in such a direction as to cause absorption of heat at the hot junction. Then if R be the whole resistance of the circuit, we have by Joule's law and the first law of thermodynamics : — EI+irI—Tir=ltI*.
Sida 233 - Perhaps the most useful application would be in the observation of zones. When the stars are somewhat scattered it would often happen that their light might be measured without any loss of time. By this instrument another field of usefulness is opened for the form of horizontal telescope advocated at a former meeting of this Academy (Proc, Amer. Acad. XVI. 364). Very perfect definition would not be required, since it would affect all the stars equally. To an amateur who would regard the complexity...
Sida 231 - To obtain the best results the work should be made purely differential, that is, frequent measures should be made of stars in the vicinity assumed as standards. Otherwise large errors may be committed, due to the varying sensitiveness of the eye, to the effect of moonlight, twilight, &c., and to various other causes. A still further simplification of this photometer may be effected by substituting the diurnal motion of the earth for the scale as a measure of the position of the star as regards the...
Sida 395 - The principal institutions of mankind originated in savagery, were developed in barbarism, and are maturing in civilization. In like manner, the family has passed through successive forms, and created great systems of consanguinity and affinity which have remained to the present time. These systems, which record the relationships existing in the family of the period, when each system respectively was formed, contain an instructive record of the experience of mankind while the family was advancing...
Sida 298 - DR. EDWARD PALMER'S present collection was made during the last six months of 1879, mostly in the region lying northwest of San Antonio, Texas, and along the routes from that place to Laredo and Eagle Pass upon the Rio Grande, and during the following year in the States of Coahuila and Nuevo Leon in Mexico. A nearly complete set of these plants was sent to the herbarium at Kew, England, and a partial list was there somewhat hastily made, which is the basis of the present one. In addition, determinations...
Sida 415 - Koting that the trap upon irritation closes .it first imperfectly, leaving some room within and a series of small interstices between the crossed spines, but after a time, if there is prey within, shuts down close, he at once inferred that this was a provision for allowing small insects to escape, and for retaining only those large enough to make the long process of digestion remunerative. To test the surmise, he asked a correspondent to visit the habitat of...
Sida 233 - Perhaps the best method with a small telescope is to measure a large number of stars whose light has already been determined photometrically, and deduce A from them. The great advantage claimed for this form of wedge photometer is the simplicity of its construction, of the method of observing, and of the computations required to reduce the results. It may be easily transported and inserted in the field of any tele-scope like a ring micrometer. The time, if the observer is alone, may be taken by a...