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II. Continuous Electrical Calorimetry. 
By Hugh L. Callendar, F.R.S., Quain Professor of Physics at University College , 
London 
Received November 18, 1901,—Read February 6, 1902. 
Table of Contents. 
Part I.—Introduction. 
Page 
(1.) General account of the Origin and Progress of the Investigation.57 
Part II.— Electrical Measurements. 
A. Potential. 
(2.) Advantages of the Potentiometer Method.60 
(3.) Description of the Potentiometer.63 
(4.) Method of Testing.65 
(5.) Method of Calibration.66 
B. Resistance. 
(6.) The Lorenz Apparatus.71 
(7.) Values of the Resistance Standards... . 73 
(8.) Comparisons at the National Physical Laboratory . . .. 75 
(9.) Hysteresis in Manganin Coils.77 
C. Current. 
* (10.) The Electrodynamometer.81 
(11.) Duplex Scale Reading.82 
(12.) The Bifilar Suspension. 83 
(13.) The Mean Radius of the Large Coils.83 
(14.) Distance between the Mean Planes of the Large Coils. . . 84 
(15.) Area of Windings of the Small Coils.84 
(16.) Ratio of the Currents in the Coils.85 
(17.) The Electromotive Force of the Clark Cell.86 
* Now Professor of Physics at the Royal College of Science, South Kensington, London, S. W. 
(313.) 11.8.02 
