388 
DR. A. W. HOFMANN’S RESEARCHES INTO THE 
The theoretical values of the formula 
C 40 H44NI = <1 
CloH 
11 
are as follows : — 
^10 H41 
^10 
.^10 
>N I 
Theorj'. 
__A_ 
1 equiv. of Tetramylammonium . . . 298*0 
1 equiv. of Iodine 127*1 
1 equiv. of Iodide 
425*1 
70*11 
29*89 
100*00 
Experiment. 
29*60 
On boiling the iodide with protoxide of silver, an alkaline, very bitter solution of 
the oxide of tetramylammonium is obtained. This substance is evidently far less 
soluble in water than the corresponding bases in the methyl- and ethyl-series. It 
would almost appear as if this compound stood to the methyl- and ethyl-bases as an 
alkaline earth does to potassa and soda. 
On adding potassa to a solution of oxide of tetramylammonium, the base rises in 
the form of an oily layer on the surface of the liquid. The same separation is ob- 
served when the solution is much evaporated; in the latter case the oily layer gradu- 
ally solidifies. On allowing a moderately concentrated solution of this base to stand 
for some time in a vessel in which it is protected from carbonic acid, magnificent 
perfectly definite crystals, sometimes an inch in length and in thickness, are de- 
posited ; they are but moderately deliquescent, and attract but slowly carbonic acid 
from the air. These crystals are the hydrate of tetramylammonium, containing a 
certain amount of water of crystallization. I have not yet been able to determine 
the number of equivalents. On heating these crystals, they fuse in their water of 
crystallization, and yield on evaporation in the water-bath a viscid semi-solid trans- 
parent mass, which is the hydrated oxide of tetramylammonium. 
^10 
l^N O, HO. 
CioH 
11 
^10 
This substance is extremely deliquescent, and opposes to an ordinary analysis the 
same obstacles which I met with in the case of tetrethylammonium. I succeeded, 
however, in the following manner, in determining with tolerable accuracy the compo- 
sition of this mass. Having observed that this oxide is far less easily decomposed by 
heat than the corresponding ethyl-compound, I endeavoured to determine the state 
of hydration in which the oxide remained, by decomposing a known quantity of the 
iodide with protoxide of silver, and evaporating the solution thus obtained in a glass 
vessel, through which a current of air previously dried and decarbonated by potassa 
