17 
Ammonia and Hydrogenium are only intimately mixed with 
the Mercury. The peculiar buttery consistence of the Amal- 
gam he attributed to inflation or frothing of the Mercury. 
If this theory be a correct interpretation of the facts the gases 
being uncombined should obey Marriotte’s law of condensa- 
tion. ‘This he considered would be the experimentum crucis 
in this case. He then prepared some of the Ammonium-Amal- 
gam in a glass tube closed at one end and submitted it to 
considerable pressure by means of a piston. The contraction 
and expansion of the Amalgam was very clearly and evidently 
seen, which was apparently proportioned to the pressure 
exerted. On increasing the pressure to six or eight atmos- 
pheres the Amalgam became liquid like Mercury and on re- 
moving the pressure it resumed its pasty condition. 
Prof. G. F. Barker, of Yale College, being called upon, 
offered some remarks. He thought Prof. Seely’s experiment 
exceedingly interesting and a valuable contribution to our 
knowledge of Ammonium-Amalgam. He questioned, how- 
ever, Prof. Seely’s hypothesis as to its constitution. He 
asked in what condition the gaseous Hydrogen and Ammonia 
might be while under pressure? There was no visible escape 
of the gases during the compression; and the fact that on 
removing the pressure the Amalgam resumed its bulky 
nature, was opposed to Prof Seely’s physical theory. 
Mr. O. Loew thought it possible to calculate the amount of 
Hydrogen developed by a certain quantity of Sodium, and if 
a portion was united with the Mercury, it would become evi- 
dent by measuring the free Hydrogen evolved. He thought 
that Prof. Seely’s experiment proved conclusively that the 
Amalgam was a chemical compound, and not a physival or 
mechanical mixture. 
Dr. I. Walz remarked, that if we adopt the physical theory, 
we must agree that a decomposition and recomposition takes 
place, each time that the pressure is applied and removed. 
Wror, Ie . 2 
