288 



MR. V. H. VELEY ON THE CONDITIONS OF THE 



Before a series of observations was commenced the above apparatus was heated to 

 a temperature slightly above that required, the olive oil expanding upwards through 

 the opened tap into the burette. The mixture of sulphuric and formic acids 

 previously made was heated independently in another flask to a temperature slightly 



Fig. 1. 



below that required ; the loss of carbonic oxide during this process was quite inappre- 

 ciable. The mixture was then poured into the bulb of the decomposition apparatus, 

 and its neck closed with the thermometer-bearing plug. When the temperature 

 appeared to be nearly constant, the tap of the burette was closed ; this caused the 

 oil to expand only in the U -tube (F), and to drive the thread of mercury down one 



