Proceedings of the American Academy of Arts and Sciences, Volume 42

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Vol. 12 (from May 1876 to May 1877) includes: Researches in telephony / by A. Graham Bell.

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Page 742 - Premium to the author of any important discovery or useful improvement in light or heat, which shall have been made and published by printing, or in any way made known to the public, in any part of the continent of America, or any of the American islands; preference always being given to such discoveries as, in the opinion of the Academy, shall tend most to promote the good of mankind...
Page 737 - If any book shall be lost or injured, or if any notes, comments, or other matters shall be written, or in any manner inserted therein, the person to whom it stands charged shall replace it by a new volume, or set, if it belongs to a set.
Page 217 - A piece of thin seamless steel tubing of such a diameter as to slip easily through the hollow cores of the electromagnet, from which the conical pole-pieces have been removed, is procured. A short piece of small brass tubing is brazed into one end, through which the tube is exhausted. A lump of sodium the size of a walnut is melted in an iron crucible, and poured out into a V-shaped trough made of thin sheet iron. As soon as the bar is solid it is placed in the iron tube, one end of which J p I Li...
Page 742 - American islands, during the preceding two years, on heat or on light; the preference always being given to such discoveries as shall, in the opinion of the Academy, tend most to promote the good of mankind.
Page 70 - Other points would have been determined, but time did not permit It is obvious that the intermediate points in the lower and in the higher octave were desirable, but no pipes were to be had on such short notice for this part of the range, and in their absence the data could not be obtained. In the diagram, Figure 7, the points lying on the vertical lines were determined the first night. The points lying between the vertical lines were determined the second night. The accuracy with which these points...
Page 571 - X 10~l° per degree, in the region between 32° and 182°. As v is proportional to the tangent of the angle of inclination of the iron line from the horizontal line on the thermo-electric diagram, the statement just made means that in the temperature region considered the iron line should be one of increasing steepness with rise of temperature. Taking the value of v at 32° as — (757 — 20 X 2) X...
Page 52 - ... absorption by the walls and contained material, or it may be regarded as a process of rapid reflection from wall to wall with loss at each reflection. In either case it is called reverberation. It is sometimes called, mistakenly as has been explained, resonance. The reverberation may be expressed by the duration of audibility of the residual sound after the cessation of a source so adjusted as to produce an average of sound of some standard intensity over the whole room. The direct determination...
Page 448 - Report on the Hydroida collected during the Exploration of the Gulf Stream by LF de Pourtales, Assistant United States Coast Survey.
Page 373 - Romanes thinks the answer is that ' the moon is a familiar object, the insects regard it as a matter of course, and so have no desire to examine it.' " Parker and Cole give a more reasonable explanation. The moths and gnats react to larger areas of light than to a point of more intense light. They therefore remain near the ground, on account of the bright patches of moonlight, instead of flying towards the moon; but if they come near a candle, the...
Page 347 - V . antiopa does discriminate between light derived from a large luminous area and that from a small one, even when the light from these two sources is of equal intensity as it falls on the animal. These butterflies usually fly toward the larger areas of light.

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