176 



MR. R. ROUTLEDGE ON THE 



drawn for an instant, so that a few drops of the acid might 

 enter the tube. The ammonia gas present was of course 

 immediately absorbed ; and the mercury having been again 

 brought to the same level in both limbs, the space occu- 

 pied by the residual hydrogen was marked on the tube. 

 The volumes occupied by the gases were determined by 

 finding the quantity of water required to fill them from a 

 burette. 



The following are the results of four experiments : — 



No. of 

 expe- 

 riment. 



Volume of 



the mixed 



gases. 



Volume of 



residual 

 hydrogen. 



Volume of 

 ammonia 

 absorbed. 



Volume of 



ammonia found 



for one volume 



of hydrogen. 



i. 



2. 



3- 



4- 



cub. cent. 



20'8 

 l8'2 

 12-8 



13-6 



cub. cent. 

 7-0 

 62 



4'3 



4-6 



cub. cent. 

 138 



I2"0 



8-5 



9-0 



197 



i'93 

 1-98 

 195 



I believe these figures are as nearly accordant with the 

 atomic proportions as could be expected from the means 

 employed, where the possible error in determining the 

 volumes might amount to perhaps *2 cub. centim. 



In another similarly conducted experiment, in which it 

 was sought to obtain as much gas as possible, the tube 

 was closed too soon ; and the result showed a deficiency of 

 ammonia, but is otherwise interesting : — 





Experiment 5. 





Volume of 





Volume of 



Volume of 



mercury in 



Volume of 



the mixed 



residual 



he amalgam. 



amalgam. 



gases. 



hydrogen. 



cub. cent. 



cub. cent. 



cub. cent. 



cub. cent. 



1 18 



3o*5 



49-0 



18-0 



A new observation on the amalgam has recently been 

 made in America by Professor C. A. Seely*, who found, by 

 subjecting it to varying pressure, that its volume changes, 



* Chemical News, June 10, 1870. 



