solids; contact, thermal and electromagnetic generation of e. m. f.; dielectric phenomena; radiation, and luminescence. No discussion. THE GENERAL EQUATIONS OF THE ELECTRIC CIRCUIT Charles P. Steinmetz Vol. xxvii-1908, pp. 1231-1305 Mathematical development and physical interpretation of general equations for the electric circuit-covering standing waves, free oscillations and traveling waves in simple and complex circuits. Numerical examples of overhead and underground power transmission circuits, and telephone, telegraph and submarine cable circuits. Discussion, pp. 1306-1307, by Messrs. Frederick Bedell, Dugald C. Jackson, H. L. Wallau; Charles P. Steinmetz and W. S. Franklin. General remarks on Steinmetz's equations. Brief exposition of Heaviside's method of explaining electric wave motion. AN IMPERFECTION IN THE USUAL STATEMENT OF THE FUNDAMENTAL Carl Hering Vol. xxvii-1908, pp. 1341-1351 Description and discussion of an experiment that tends to show that present methods of teaching do not give a clear conception of the fundamental law of electromagnetic induction. Discussion, pp. 1352-1371, by Messrs. Charles P. Steinmetz, A. E. Kennelly, Elihu Thomson, W. S. Franklin, Percy H. Thomas, W. P. Graham, George T. Hanchett, George A. Campbell, Tracy D. Waring and Carl Hering. General remarks on the laws of electromagnetic induction and criticisms of the author's experiment. R. E. Hellmund GRAPHICAL TREATMENT OF THE ROTATING FIELD Vol. xxvii-1908, pp. 1373-1394 Development of a graphical method of investigating a rotating field and examples of its application. Discussion, p. 1395, by Messrs. Comfort A. Adams and R. E. Hellmund. A TRIGONOMETRIC METHOD FOR THE SOLUTION OF ALTERNATING-CURRENT PROBLEMS Harold Pender Vol. xxvii-1908 pp. 1397-1424 Development of a short method for solving alternating-current problems with examples of its application to single-phase and three-phase transmission lines, transformers and induction motors. Tables of reactance, capacity, resistance and drop factors for use in such calculations. Discussion, pp. 1424-1427, by Messrs. Comfort A. Adams, W. A. Del Mar and L. W. Rosenthal. Magnitude of errors involved by this method when applied to transmission line calculations. EVEN HARMONICS IN ALTERNATING-CURRENT CIRCUITS Vol. xxviii -1909, pp. 725-732 John B. Taylor Description of conditions under which even harmonics may be produced in commercial circuits, with special reference to the effect of stray direct current on the performance of stationary transformers. Tests and oscillograms of transformer exciting current with stray direct current in the windings. Discussion, pp. 733-736, by Messrs. Frederick Bedell, V. Karapetoff, Charles F. Scott, Charles P. Steinmetz and John B. Taylor. Production of even harmonics in alternators and effect of direct-current in the windings of a transformer upon the losses. VECTOR POWER IN ALTERNATING-CURRENT CIRCUITS A. E. Kennelly Vol. xxix-1910, pp. 1233-1267 Analytical study of vector quantities combating the use of wattless power and wattless current, and advocating the standardization of the counter-clockwise rotation of vectors. Discussion, pp. 1268-1280, by Messrs. C. P. Steinmetz, Gano Dunn, William W. Crawford, John B. Taylor. L. T. Robinson, F. Creedy and A. E. Kennelly. Polar diagram vs. the crank diagram for vector representation of alternating quantities. Representation of vector power by Mobius & Grassman system of point-analysis. 3. MEASUREMENT AND INSTRUMENTS A. UNITS, STANDARDS AND LABORATORIES Clayton H. Sharp Discussion, incorporated with that of paper by William J. Hammer on "Edison's Tungstate of Calcium Lamp-The Nernst Lamp-Radium, Polonium and Actium." THE PRESENT STATUS OF THE QUESTION OF A STANDARD OF LIGHT Clayton H. Sharp Vol. xix-1902, pp. 55-57 Brief reference to some of the shortcomings of the present standards of luminous intensity. Advantages of acetylene flame as standard. Discussion, incorporated with that of paper by William J. Hammer on "Edison's Tungstate of Calcium Lamp-The Nernst Lamp-Radium, Polonium and Actium." MAGNETIC UNITS AND OTHER SUBJECTS THAT MIGHT OCCUPY ATTENTION A. E. Kennelly Discussion, pp. 537-538, by Messrs. Carl Hering, W. E. Goldsborough and J. P. Jackson. THE LEGALIZED STANDARD OF ELECTROMOTIVE FORCE Henry S. Carhart Vol. xxii-1903, pp. 521-523 Legally determined values of e. m. f. of the Clark standard cell. Ratio between the Clark and Weston cells. Reasons for recommending the adoption of the Weston cell as standard. Discussion, pp. 524-527, by Messrs. C. H. Sharp, Carl Hering and W. E. Goldsborough. Importance of standard cell and potentiometer in practical work. Motion passed to refer specifications for standard cell to Board of Directors. THE NATIONAL BUREAU OF STANDARDS S. W. Stratton and E. B. Rosa Vol. xxiv-1905, 999-1050 Description of the Bureau of Standards, its origin, functions, organization, equipment and work. Also a description of the laboratory at the Louisiana Purchase Exposition. Discussion, incorporated with that of paper by Clayton H. Sharp on "A Testing Laboratory in Practical Operation." A TESTING LABORATORY IN PRACTICAL OPERATION Clayton H. Sharp Discussion (including that of paper by S. W. Stratton and E. B. Rosa on "The National Bureau of Standards"), pp. 1061-1065, by Messrs. F. B. Crocker, W. E. Goldsborough, C. O. Mailloux, George F. Sever, C. A. Doremus, William McClellan, S. W. Stratton, John W. Lieb, Jr., and E. B. Rosa. General remarks on the scope and importance of standardization laboratories. Desirability of international standardization. PRIMARY STANDARD OF LIGHT Charles P. Steinmetz Vol. xxvii-1908, pp. 1319-1324 Criticism of primary standard based on energy of radiation, recommending standard composed of three component colors of definite wave lengths. Discussion, pp. 1325-1339, by Messrs. A. E. Kennelly, Edwin P. Hyde, W. S. Franklin, Carl Hering, Clayton H. Sharp, C. A. Perkins, John B. Taylor, E. B. Rosa, H. S. Carhart and Charles P. Steinmetz. General remarks on Steinmetz's proposed standard. Motion carried to refer question of establishing standard to the Bureau of Standards. B. ELECTRICAL MEASUREMENTS AND INSTRUMENTS Vol. xviii-1901, pp. 169-183 Description of the theory of operation, the design and construction of the transformer. Account of tests demonstrating the degree of accuracy under various conditions, such as occur in testing switchboard instruments in place. Discussion, pp. 184-190, by Messrs. Geo. T. Hanchett, Gano S. Dunn, Samuel Sheldon, A. E. Kennelly, C. O. Mailloux and Townsend Wolcott. Criticism of the method and answers thereto. Paul M. Lincoln SYNCHRONISM AND FREQUENCY INDICATION Vol. xviii-1901, pp. 255-270 Description of construction and theory of operation of the Lincoln synchroscope and the Lincoln frequency indicator. Discussion, incorporated with that of paper by William Hand Browne, Jr., on "Power-Factor Indicators." Caryl D. Haskins SOME FUNDAMENTALS OF ELECTRIC METERS Vol. xviii-1901, pp. 271-276 Discussion of the relations between torque, friction and permanency under various surrounding conditions. Discussion, incorporated with that of paper by William Hand Browne, Jr., on "Power-Factor Indicators." METERING OF ELECTRICAL ENERGY Harry P. Davis Vol. xviii-1901, pp. 277-285 Requirements of a good energy meter and choice of meter rating for different kinds of load based on extensive experience. Discussion, incorporated with that of paper by William Hand Browne, Jr., on "Power-Factor Indicators." POWER-FACTOR INDICATORS William Hand Brown, Jr. Vol. xviii-1901, pp. 287-312 General discussion of power-factor regulation and methods of measuring power-factor. Description of numerous types and forms of powerfactor meters, phase-meters and wattless power meters, and wattless current meters, with short description of the theory of each general type. Discussion (including that of paper by Paul M. Lincoln on "Synchronism and Frequency Indication"; paper by Caryl D. Haskins on "Some Fundamentals of Electric Meters"; paper by Harry P. Davis on "Metering of Electrical Energy"), pp. 313-338, by Messrs. W. S. Barstow, Chas. P. Steinmetz, H. W. Buck, Gano S. Dunn, Ralph D. Mershon, C. F. Scott, Carl Hering, C. O. Mailloux, F. S. Holmes, E. A. Sperry, Henri Boy De La Tour, Henry W. Fisher, H. G. Stott, Chas. Janisch and C. D. Haskins. Relative merits and comparative performance of direct-current and induction motors. Desirability of charging for apparent and quadrature power. Two-rate meter for peak load differentiation. LIQUID POTENTIOMETER; DETERMINING ELECTROLYTIC RESISTANCES Carl Hering Vol. xix-1902, pp. 317-323 Description of the instrument and methods of using it. Discussion, incorporated with that of paper by W. R. Whitney on "Colloids." THE ELECTROSTATIC WATTMETER IN COMMERCIAL MEASUREMENTS Miles Walker Vol. xix-1902, pp. 1035-1045 Discussion of the advantages and disadvantages of the Electrometer. Simple formulas for calculating the torque on the vanes of an electrometer under various practical conditions. Description of a bifilar suspension electrometer. Discussion, incorporated with that of paper by Charles Edward Skinner on "Energy Loss in Commercial Insulating Materials When Subjected to High-potential Strains." Robt. B. Owens A NEW CURVE TRACING INSTRUMENT Vol. xix-1902, pp. 1123-1129 Description of the instrument and directions for checking current and |