( 510 ) 



the rise of the level in 7>„j. \\v once more beoin to diniiiiisli the 

 pressure ( )\^ shut, V^^ open) \\ hieh process generally lakes some 

 time. Tlien more liipiid is admitted as before and if necessary this 

 process is rei)ealed several times, if the beaker is sufficiently tilled 

 at the desired recbiced pressure we begin to regidale the pressure 

 with ihe duly e.xhaiisled vacuum reservoir as descril)ed al)ove. 



Plate III shows a couple of grajjliical representations of the varia- 

 tions of the temperature of tlie l)atli. The ordinates show the deflec- 

 tions on tlie scale of the galvanouieter in centimeters. Tlic abscissae 

 represent the time in minutes; fig. 1 relates to a measurement in 

 methane at ordinary pressure; a deflection on the scale of 1 cm. 

 corresponds to alxjut 0.009 deg. (the open space in the figure indi- 

 cates a magnetic disturbance). Fig. 2 refers to oxygen at a diminished 

 pressure; here a delleclion on tlie scale of I cm. corresponds to 

 0.005 deg. They were borrowed from the measurements of Meili.nk 

 mentioned above. 



The temperature of the measurement is determined by the help 

 of graphical representations, extending over the whole time of 

 measurement, tVoui Avhich the poi'tions rei)roduced on plate 111 ha\<> 

 been taken. For tills determination the readings of the galvano- 

 meter are noted down about twice every minute. By means of the 

 planimeter we derive from the graphical representation obtained, the 

 mean ordinate, which mean is considered as the temperature of the 

 bath during the whole measurement. 



(March 25, 1903). 



