by means of the interferometer. One hundred and eighty-nine faint lines in the visible and infrared neon spectrum (5343A to 8783A) have been measured by means of a concave grating. K. Burns, W. F. Meggers and P. W. Merrill, Bureau of Standards, Washington, D. C. [Neon is a gas which has some promise of practical use for illumination purposes in electric lamps of the vacuum-tube type. Lamps of this type are in an experimental stage and have been shown on one or two occasions. Editor.] Transformations, Electric, Possible with Stationary Apparatus. A mathematical investigation has been made of inherent limitations of current and voltage transformations possible by means of a network constituted of self and mutual inductors, resistors and condensers. Expressions have been derived for electrostatic and electromagnetic energies, Joulean heat dissipation and power, in complex quantities. The purely imaginary part of the expression for power in a static network is shown to be equal to 2 w times the difference between the mean electromagnetic energy and mean electrostatic energy, where w = 2 f. Use is made of this new principle in considering the problems of power-factor correction and phase splitting. In general, for phase transformation by static apparatus both magnetic and electrostatic storage of energy are necessary, and it has been shown how the mini mum amounts of each are determined by the load. The symmetry of the coefficients in the general equations for the steady state in a static network is demonstrated, and it is shown that limitations upon voltage and current transformations follow. The voltage regulation of any phase-splitting arrangement has also been considered. J. Slepian, Pittsburgh, Pa. INDUSTRIES AND BUSINESS On our shelves is the most complete stock of technical, industrial, engineering and scientific books in the United States. The technical literature of every trade is well represented as is also the new literature relating to scientific management, business efficiency, advertising and the various other subjects related thereto. A large number of these we publish and for an ever increasing number we are the sole agents. ALL OUR INQUIRIES ARE CHEERFULLY |