1C4 ANNUAL OF SCIENTIFIC DISCOVERY. 



drogen thus developed was, in several experiments, from 100 to 

 150 times that of the mercury employed. This hydrogen pos- 

 sesses a faint odor. 



"When this amalgam of hyclrogeninm is pressed, directly 

 after its preparation, between sheets of filtering paper, and then 

 spread out in a layer to the air, the temperature soon rises con- 

 siderably, and vapors of water are formed, which may be 

 condensed in a glass receiver. The finely divided platinum 

 present is obviously the cause of this rapid oxidation of the hy- 

 drogenium. In this action of bichloride of platinum upon zinc- 

 amalgam oxychloride of zinc is at the same time formed ; and 

 though this maybe removed by means of chlorhydric acid, yet by 

 this treatment a part of the hydrogenium-amalgam is destroyed. 

 If after this it be washed with water, it undergoes a very slow 

 decomposition, the volume increases, and bubbles of hydrogen 

 escape through the water above. 



" Platinum, after perfect amalgamation, does not act as en- 

 ergetically as in its nascent state ; that is, when precipitated on 

 the amalgam. When platinum-amalgam is mixed with zinc- 

 amalgam the decomposition of the water by the zinc is extremely 

 slow, and the hydrogenium-amalgam does not appear for some 

 time. Under certain conditions, moreover, the hydrogeuium- 

 amalgam is formed without the aid of the bichloride of platinum. 

 I had at one time about 20 pounds of mercury containing zinc, 

 which was left standing in a bottle with water for 3 weeks ; the 

 hydrogenium-amalgam formed on the surface of the mercury, 

 gradually decomposing above and being renewed from below." 

 0. Loew. Annals Lyceum Natural History of New York. 



AMMONIUM-AMALGAM. 



The existence of ammonium NH4, as such, in what is known as 

 ammonium-amalgam, has never been demonstrated, although its 

 constituents escape in proper proportions from the amalgam. If 

 the hydrogen escaping from the amalgam, together with the 

 ammonia (NHs), be shown to be in the nascent state, it would be 

 evidence that it had just been in chemical combination with the 

 ammonia; in other words, that metallic ammonium existed in the 

 amalgam. Some pellets of sodium were placed in contact with 

 some particles of the transparent variety of phosphorus, wrapped 

 in bibulous paper and plunged beneath the surface of water. A 

 red glow was seen ; and as the nascent hydrogen came in contact 

 with the phosphorus, bubbles of phosphide of hydrogen were 

 formed. Occasionally one would inflame as it came into contact 

 with the atmosphere, placing the nature of the reaction beyond 

 a doubt. As phosphide of hydrogen cannot be formed by direct 

 synthesis if ordinary free hydrogen be employed, this becomes a 

 test for the presence of that gas in its nascent state. The hydro- 

 gen escaping from the ammoniacal amalgam was now tested by 

 this process. A sodium-amalgam, dipped beneath a solution of 

 chloride of ammonium, was employed ; and it became necessary 



