the Thermometric Anemometer. 



693 



distance between the latter and the second thermometer 

 assumed the values 30, 15, 75 ; 6'3, 3*0, 1*1, 0'5, and 0'15 

 cm., as indicated by the respective curves. The initial 

 portions of some of the curves are plotted on an enlarged 



DISTANCE 8ETWKN HEATING COIL 

 AND SECOND THERMOMETER (CMS) 

 O30. X 15. + 7-5, A 6 3. 

 D3-0, II . ^0-5,QOl5 



iO 20 30 40 SO 



Velocity (cms. per sec, volumes reduced to o'c and 760 mm.) 



scale in fig. 2 a. The variation o£ distance between the 

 heating element and the second thermometer affords a 

 convenient method of studying the effect of a variation of 

 the heat losses due to radiation etc. upon the form of the 

 calibration curves. The broken line B in the figure gives 

 the theoretical form — a straight line passing through the 



