( 205 ) 



was once more compeared with the open standard-manometer. It 

 proved that the normal volume had again undergone a slight dimi- 

 nution, i.e. of 0.00026 of the original value. This comparison was 

 made at about 22, 28 and 55 atmospheres. If the calculations of the 

 pressure are carried out with the corrected normal volume, the 

 remaining differences between the indications of the open and the 



1 

 closed manometer are smaller than of the total pressure. 



The steeltube ƒ, with hexagonal portion f\ on the stem of the piezo- 

 meter b s (cf. fig. 2 PI. II Comm. N°. 69, for the details at the top 

 of the tube compare fig. 4 ibid ƒ,, ƒ„ ƒ,) was soldered to the glass 

 stem & 5 in the way described in Comm. N°. 94 6 . Now the packing 

 could be pressed down more tightly (cf. § 4 Comm. N°. 97") without 

 danger of the block sliding from the stem. 



The dimensions of the different parts of the piezometer were 

 about the same as in the determinations of series I of Comm. N°. 97". 

 The glass stem had a greater length and a volume of about 12 cm 3 ., 

 which enabled us to determine a greater part of the isotherms than 

 was possible in series I. The reservoir had the somewhat smaller 

 volume of 5.1583 cm 3 . 



§ 16. Second group of values of pv,i . 



In table XIX the results of (he determinations have been given 

 in the same way as in Table XII of Comm. N°. 97". 



In conclusion we express our hearty thanks to Mr. J. Clay for 

 his valuable assistance in this investigation. 



