200 DRS. T. L. BRUNTON AND J. T. CASH ON CHEMICAL CONSTITUTION, 
response to indirect stimulation is, however, much feebler than to direct. The tetanus 
of both is impaired, but especially that of indirect stimulation. The total failure of 
reaction upon stimulation of the nerve frequently occurs whilst the muscle yields a 
moderate tetanus. If the heart has not been arrested by the injection of too large a 
dose of ammonium iodide before the circulation has distributed the poison sufficiently, 
it is often found that stimulation of the nerve does not produce any contraction, or 
it may be only a few faint twitches of the muscle. In poisoning by the phosphate 
of ammonium direct stimulation produces, as a rule, a tolerably good, though pro¬ 
longed contraction, but the failure of reaction to direct and indirect stimulation is 
more parallel than in poisoning by the iodide, and if the irritability of the nerve 
is entirely lost, it is usually found that the muscle when stimulated directly contracts 
but very feebly even to the strongest tetanising current. A m monium sulphate 
paralyses both muscle and nerve. The reactions given by the former are, however, 
longer, and outlast those of the latter. The tetanus curve of both is feeble, even 
in cases of rapid poisoning. 
Action of Compound Ammonias. 
Our experiments with these bodies were made upon frogs, rats, and rabbits. The 
substances employed, twenty-six in number, were :—Ethylamine, trimethylamine, 
triethylamine ; the chlorides of methyl-ammonium, ethyl-ammonium, amyl-ammonium, 
dimethyl-ammonium, diethyl-ammonium, trimethyl-ammonium, and triethyl-ammo¬ 
nium ; the iodides of methyl-ammonium, ethyl-ammonium, amyl-ammonium, dimethyl- 
ammonium, diethyl-ammonium, trimethyl-ammonium, triethyl-ammonium, tetramethyl- 
ammonium, and tetraethyl-ammonium ; the sulphates of methyl-ammonium, ethyl- 
ammonium, amyl-ammonium, dimethyl-ammonium, diethyl-ammonium, trimethyl- 
ammonium, and triethyl-ammonium. The action of all these bodies was tested in 
Frogs, but the whole of the series was not investigated in Rats and Rabbits. All 
the salts of the compound ammonias which we used were obtained from Messrs. 
Hopkins and Williams, who prepared them expressly for us, and guaranteed their 
purity. The poison was in all cases administered by subcutaneous injection. 
We have compared first the action of the compound ammonias, uncombined with an 
acid radical, with the action of ammonia itself. We have then compared the actions 
of the chlorides, iodides, and sulphates, of the compound ammonias with each other, 
and with the corresponding salts of ammonium. It will be noticed that there is a 
considerable difference between the action of the compound ammonias and of am¬ 
monia. The tendency to produce tetanus resembling that of ammonia was noticed in 
ethylamine, which was the only one of the compound ammonias containing only one 
atom of hydrogen, replaced by a radical, that we investigated in a free state, uncom¬ 
bined with acid. When used as a chloride, the convulsive action was less marked. 
The substitution of even a single atom of hydrogen by an alcohol radical appears to 
