M. R. Bunsen on the Law of Absorption of Gases. 181 



hint that the " Glottalite " of Thomson, of which only one speci- 

 men has been found, and about which nothing is known, may 

 turn out to be nothing but an impure mixture of Edingtonite and 

 harmotome (which, as we have stated, invariably accompanies it) ; 

 the locality and characters are much the same. Turner mistook 

 lime for barytes, and why not Thomson, who had before made 

 the same mistake. Granting this error, both contain the same 

 elements ; the quantity of silica, which no one could mistake, 

 agrees, and a person not very conversant with crystallography 

 might fancy he saw both octohedrons and cubes in the faces of 

 Edingtonite, especially when the "'crystals were so mixed together 

 that only a small portion of each could be seen." We may also 

 mention that " Glottalite " was procured from the same dealer 

 from whom we purchased cur Edingtonites. 



XXVII. On the Law of Absorption of Gases. By R. Bunsen. 

 [Concluded from p. loO.j 

 9. Oxygen in Water. 



OXYGEN gas, prepared in the usual manner from chlorate 

 of potash, gave, — 



During the agitation in the absorptiometer the water became 

 turbid from the formation of a black powder, and it was feared 

 that the metals dissolved in the mercury Lad been oxidized at 

 the expense of the oxygen in the water, and hence too large a 

 coefficient obtained. The mercury employed was therefore puri- 

 fied from all foreign metals, as perfectly as several long digestions 

 with concentrated nitric acid would permit. The experiment 

 conducted with the purified mercury gave the following results : — 



