EVERYONE who has been intimately connected with any large manufacturing companies, especially those manufacturing machines such as lathes, planers and other tools, will recall the activities of certain attaches of the companies who were recognized as employed for the specific purpose of suggesting and devising improvements in the machines. These inventors spent many hours daily in the shops seeking here and there the improvements which might place the machines produced by the company in a better position for competition with those of other makers. Many of the large industrial corporations of the country have intimate connection with groups of inventors especially skiIled in certain directions. From the foregoing it is readily appreciated that the problems presented to many of our industrial organizations necessitate the employment by them of men of scientific and technical training, graduates of our colleges and technical schools, or those trained in the school of experience, who being presented with a problem and having knowledge and originality, can, if the occasion demands, create inventions. It is not surprising, therefore, to find that to these men, the identity of whose inventions is often lost in that of the organizations of which they are a part, we owe many of the improvements which mark our industrial progress. The employment of technically trained men by the large companies will be found extending throughout many arts, but it is natural that it should be found especially emphasized in the electrical and metallur- gical developments to which much of what follows will be confined, serving to illustrate the importance, in fact the practical necessity, of the inventor as an adjunct to large industrial corporations. While it is impossible within the limits of this article to enumerate alI such that are worthy of mention, a few illustrative cases will serve to indicate how greatly we are indebted to thesf men for the advances made in the arts. The meta1urgical art furnishes many interesting examples of difficult problems met and solved by men of genius in the line of their employment. To illustrate, it would perhaps scarcely occur to ohe not confronted by the fact in actual working, that the variable quantity of moisture in the atmosphere might produce a deleterious effect in the operation of blast furnaces and steel converters which, as is well known, consume large quantities of air, the former in the process of reducing the oxides of iron, and the latter in the oxidation of certain impurities. Nevertheless, it is a fact that the presence of moisture in appreciable quantity is injurious because it absorbs heat due to its decomposition at high temperatures, and moreover, the variations in the quantity of moisture produce corresponding irregularities in the quality of the product. It is estimated that between sixty and two hundred and forty gallons of water per hour may be delivered to&blast furnace in this manner. The effect can readily be appreciated. Since the air must be supplied under pressure and in enormous quantities, the use of chemical agents for removing the moisture does not offer a ready solution of the problem. The difficulty was effectually solved, however, by James Gayley, who devised a system wherein the air, under pressure, in its passage between the blast engine and furnace or converter, was cooled in successive stages by contact with a series of pipes arranged to conduct a refrigerating fluid across the direction of the air current. The air before being fed to the furnace or converter was, in this way, cooled to a temperature at or below zero degree Centigrade, which caused the precipitation of the greater portion of its moisture. The water of condensation was then drawn oft through pipes provided for that purpose. In this way, substantially dry air was provided, the amount of moisture being practically uniforn from day to day. To William R. Jones we are indebted for a method of cheapening the cost of production of Bessemer steel. Prior to his invention the indireCt or cupola process was generally used in this country. This process consisted in running molten metal from the blast furnace into pigs; these after cooling were carefully assorted, broken up and remelted in cupola furnaces from which the molten metal was conveyed to the converter for conversion into steel. Many attempts were made to eliminate the costly intermediate steps by supplying the converter direct from the blast furnace, but the fluctuations in the chemical composition of the metal from the blast furnace were such as to render the final product of the converter of uncertain character. The necessity for obtaining a uniform product will readily be appreciated when we consider the annual fatalities due to broken rails alone. The November 18, 1911 SCIENTIFIC AMERICAN 449 problem was happily solved by Jones in a manner at once simple and efcacious. He conceived the idea of employing a large covered reservoir between the blast furnaces and converters which should receive the molten metal from the blast furnaces and maintain it in a molten state in such quantity that its average compos!tion would not be materially altered by the addition from time to time of much smaller quantities of variable composition. From this mass of substantially uniform composition the converters were supplied, and the resultant steel product derived was substantially uniform. This invention iustrates in a forceful way the familiar fact that often the simplest expedient reveals the highest degree of invention, and also shows what small diferences often lie between success and failure, for the chief diference between Jones' device and prior known devices resided in the size of his reservoir whereby he was able to obtain metal of substantially constant composition. Perhaps nowhere is the efciency of organized efort better illustrated than in the advances made in the arts by the engineering departmemts of the electrical companies. In the telephone art appear such names as Scribner, a prolifc inventor who has done much to standardize telephone installations, and Dean and Dunbar, to whom is due much credit for the development of the so-called two-wire switchboard system whereby the third wire of previous systems is dispensed with. Worthy of special mention, also, is the invention by Schellenger of the four-relay cord circuit, a form now widely used in many telephone systems, in which its use is held to b practically indispensable. Entitled to special note also is the invention by White of the so-called solid back transmitter, which has been a standard for many years. Charles P. Steilnetz, head of the electrical engineering department of one of the large electrical companies, has done much constructive work in the electrical art, having made many important inventions In alternating current motors, generators, converters, regulators, lighting and the like, but perhaps his greatest contributions to the art are his remarkable mathematical treatises on the subject of alternating current phenomena, which are standard text books in electrical engineering, as well as books of reference for the practical engineer. The mathematical accuracy of physical laws of action is well exemplifed in the phase-transformer, independently invented by Steinmetz and Charles F. Scott, a prominent engineer of another company. This device, though structurally simple, would not have occurred save to one skilled in the mathematics of mechanics. The value of the invention lies in the fact that it enables current to be transmitted of a number of phases capable of the most economic transmission, and then, by the use of the transformer, to be changed to a number of phases best adapted to local needs, as from a three-phase transmission line to a two-phase motor. The transformer consists merely of several primary and secondary coils so connected and inductively arranged that the electromotive forces in the primary circuit are resolved into components corresponding to the number of phases desired, thus inducing electromotive forces of the same number of phases in the secondary coils, which supply the secondary circuit. Dr. Elihu Thomson, one of America's leading authorities on matters electrical, is regularly employed by a large electrical company. His work on high potential and high frequency apparatus and also on electric welding is notable. Many important inventions have been made in electric meters by Schellenberger, Pratt, Tingley, Conrad, Davis, Bradshaw, and other engineers of the various companies, while the synchronizer of Lincoln, which enables the phase and frequency of an incoming generator to be determined preliminary to connecting it to line, is also a valuable addition to its art. Of particular importance among regulators for electric systems is the invention by Tirrill of the regulator which bears his name. The characteristic which renders this regulator of particular value is the quickness with which it acts to control the generator voltage responsive to changes in the load on the line. Much progress has been made by the engineering corps of the electrical companies in the electrifcation of railways and interurban lines. Prior to the present decade direct current only wal available for railway purposes. This could not be economically employed on the longer lines owing to the difculties of transmission at ordinary voltages and the heavy sparking at the brushes encountered when higher voltages were used. On the other hand, alternating current, which can be efciently transmitted to relatively great distances at ordinary voltages, could not be employed because no thoroughly satisfactory variable speed alternating current railway motor had as yet been devised. Within the past decade, however, not only has the length of direct current systems been increased by the employment of interpole generators and motors of ef-cient design, which has rendered the use of much higher voltages .possible, but also the problem of the alternating current variable speed railway motor has yielded to the ingenuity of engineers in charge of construction work of this character, and successful variable speed alternating current railway motors are now in operation on many of our roads, notably the New York, New Haven and Hartford. Prominent among the inventors of this country in the development or the alternating current railway motor are Lamme, Alexanderson and Milch, while abroad much valuable work of a pioneer character has been done by such prominent engineers as Winter, Eichberg, La-tour, Deri, and others. Few felds have claimed more attention recently than that of lighting, and many important improvements in this art have resulted from the extensive experiments conducted by the well-organized departments of the various electric companies. Just and Hanaman have done much to develop the tungsten light, and Kuzel also has rendered efcient service in this line, the latter having invented the colloidal process for the manufacture of tungsten flament. The importance of the tungsten light will be readily appreciated from the fact that for the same amount of current it furnishes substantially 100 per cent more light than the ordinary carbon lamp. Prominent in the development of the faming arc are the names of Steinmetz, Dempster and Ladof, while the names of Steinmetz, Thomas, Weintraub, and Kruh are conspicuous in the development of the mercury vapor lamp which, owing to the uniform distribution of its light and the absence of sharply defned shadows, renders it admirably adapted for use in machine shops, drafting rooms, and like places, in which it has found extensive use. The mercury vapor lamp, suitably modifed, is also used as a rectifer of alternating currents, especially in the charging of storage batteries from an alternating current source of supply, since it occupies little space and is inexpensive and simple in operation. Further enumeration might be continued almost indefnitely, but the few instances selected will indicate to how great an extent the development of the arts is due to the inventor whose invention is often not associated with his name.