November 9, 1900. ] 



SCIENCE. 



705 



convey some impression, though an imper- 

 fect one, of the extent of the work ac- 

 complished : 



FIRST (physical) DIVISION. 



I. Work in Heat. — Determination of the density of 

 ■water between 0° C. and 40° C. 



Determination of the pressure of water vapor at low 

 temperatures. 



Determination of the pressure of water vapor near 

 50° C. 



Investigations of thermometers for temperatures be- 

 tween 100° and 200° C. 



Investigation of the nitrogen thermometer with a 

 platinumiridium bulb for very high temperatures. 



Investigation of thermometers for low tempera- 

 tures. 



Determination of the thermal and electrical con- 

 ductivity of pure metals. (These determinations are 

 to be extended down to the temperature of liquid air 

 and up to 1,000° C.) 



Investigations with the Fizeau-Abbe dilatometer. 



Investigation of the transmission of heat through 

 metal plates. 



II. Work in Electricity. — Comparison of the normal 

 wire resistances of Divisions I and II. 



Determination of the capacity of an air condenser. 



Comparison of the standard cells of Divisions I and 

 II. 



Determination of the conductance of water solu- 

 tions with a higher degree of accuracy than has been 

 attained hitherto, especially with dilute solutions. 



III. Work in i?^^^.— Investigation with electrically 

 heated black bodies. 



Proof of Stefan's law between 90° and 1,700° abso- 

 lute temperature. 



Determination of the relation between the intensity 

 of light and the temperature. 



Measurement of radiation in absolute measure. 



Determination of the distribution of energy in the 

 spectrum of black bodies. 



Determination .of the distribution of energy in th g 

 spectrum of polished platinum and other substances ; 

 also their reflective power. 



SECOND (technical) DIVISION. 



I. Work of 3Iechanical Precision. — Investigation of 

 the errors of length and of the division of 300 scales, 

 tubes, etc. 



Coefficient of expansion of 18 bars, tubes and wires. 



Verification of 86 tuning forks for international 

 pitch. 



Construction of a new transverse comparator. 



Study of the variations of angular velocity of rota- 

 ting bodies. 



II. Electrical Work. — Calibration of direct current 

 apparatus, 183 pieces. 



Calibration of alternating current apparatus, 58 

 pieces. 



Examination of other electrical apparatus, 76 ar- 

 ticles. 



Examination of accumulators, primary elements 

 and switches, 37 articles. 



Examination of insulating and conducting mate- 

 rials and carbons, 23 articles. 



Installation of storage cells for a current of 10,000 

 amperes. 



Installation of small storage cells for an electric 

 pressure of 20,000 volts. 



Installation of alternating current instruments for 

 measuring potential difference up to 500 volts and 

 current up to 100 amperes. 



Examination of 29 samples of alloys for specific re- 

 sistance and temperature coefficient. 



Examination of 126 samples of insulating materials 

 with an electric pressure up to 800 volts. 



Verification of single resistances, 123 samples. 



Calibration of 33 resistance boxes, compensation 

 apparatus, etc., containing 1,153 resistances. 



Comparison and verification of 133 standard cells — 

 111 Claik and 22 Weston elements. 



Determination of the ratio Clark 15° C. to cadmium 

 20° C, and Clark 0° C. to cadmium 20° C. with a 

 large number of standard cells. 



Examination of 21 samples of dry and storage cells. 



Calibration of 25 galvanometers to measure high 

 and low temperatures with thermal elements. 



Magnetic examination of 25 samples of iron and steel. 



Investigation of the difference between the contin- 

 uous and the discontinuous magnetization of steel. 



Investigation of the influence of repeated heating 

 on the magnetic hardness of iron. 



III. Work Relating to Heat and Measurement of 

 Pressure. — Calibration of 18,777 thermometers. 



Examination of 4 safety appliances and benzine 

 lamps. 



Calibration of 317 thermal elements. 



Verification of 9 manometers and 22 barometers. 



Testing of 190 samples of apparatus for petroleum 

 investigations. 



Testing of 3,210 samples of safety rings and plugs. 



Testing of 32 samples of indicator springs. 



IV. Work in Light. — Testing of 119 Hefner lamps 

 for photometric purposes. 



Testing of 189 incandescent lamps. 



Testing of 143 gas and other lamps and adjunct ap- 

 pliances. 



Investigation of the relation between the tempera- 

 ture of sugar solutions and their rotary power on po- 

 larized light. 



