208 



FRANKLAND'S METHOD OF GAS ANALYSIS. [BOOK i. 



graduation, what volume of air or water (as the case may be) the tube 

 contains, when the upper convex surface of the mercury stands exactly level 

 with it. For this purpose the orifice a is connected by means of an 



FIG. 46. FRANKLAND'S SMALLER APPARATUS FOR THE ANALYSIS OF GASES BY THE 

 OF LIQUID REAGENTS. (From Sutton's Volumetric Analysis.) 



- 



india-rubber tube with a reservoir (a funnel) containing distilled water. 

 The mercurial column is then allowed to descend until it stands exactly at 

 zero. A weighed beaker having been then placed under a, water is expelled 

 till the column stands at a height of fifty millimetres, and the beaker again 

 weighed. In a similar manner the outflow of the water corresponding to a rise 



i 



