400 Chronicles of Science. [July, 



but leaves from 7 to 13 per cent, of residue. The taste of Russian 

 isinglass is pleasant and sweet ; it yields a very firm gelatine, which 

 is perfectly transparent. The Bengal, or Indian kind, often has a 

 fishy taste, and the gelatine it yields is not clear. The Brazilian 

 isinglass yields an opaque, milky-looking gelatine, and its taste is 

 acrid. China isinglass is a rare article in the European markets. 



An important reaction in synthetical chemistry has been pub- 

 lished by Dr. E. Boyer, who has effected the formation of formic 

 acid from carbonic acid. The author states that, while submitting 

 to the action of a current of electricity an aqueous solution of car- 

 bonic acid, the latter was simply converted into formic acid by the 

 addition of hydrogen. 



Owing to the fears of a quinine famine expressed some years 

 ago, great efforts were made to introduce the cultivation of cinchona 

 trees in numerous new localities. We have recently heard of the 

 first importation of cinchona bark from Java, a quantity of some 

 ^30 lbs. of this bark having been exported from Java to the 

 Netherlands. According to analysis made by Dr. B. Moens in 

 Java, this bark contains from 2*4 to 7'5 per cent, of alkaloids, of 

 which quantity 0'59 to 3*67 is quinine. The loss of weight occa- 

 sioned by the drying of the bark has been found to amount to 66 

 per cent. There is every prospect that within some six or seven 

 years hence Java will largely export this drug ; and the cultivation 

 of the cinchona trees is also to be extended to Sumatra, Celebes, and 

 the Moluccas. 



Dr. Loew has made known a fact which renders still more pro- 

 bable the Hydrogenium theory of the late Professor Graham. 

 The researches of Graham went to show that hydrogen could be 

 alloyed with palladium, and that it was also contained in meteoric 

 iron. He condensed the hydrogen in the palladium, and came 

 nearer proving its metallic character than any other person had done. 

 Dr. Loew has succeeded in combining hydrogen with mercury. 

 He takes an amalgam composed of not more than 3 or 4 per cent, 

 of zinc, and shakes it with a solution of bichloride of platinum ; the 

 liquid becomes black, and a dark powder settles to the bottom. 

 The contents of the flask are then thrown into water and hydro- 

 chloric acid added to dissolve the excess of zinc. The amalgam of 

 hydrogen and mercury at once forms in a brilliant voluminous 

 mass, resembling in every way the well-known ammonium amalgam. 

 It is soft and spongy, and rapidly decomposes, but without any 

 smell of ammonia. The hydrogen escapes, and soon nothing but 

 pure mercury is left in the dish. The experiment appears to show 

 that an amalgam of hydrogen and mercury can be formed, and that 

 hydrogen is really a metal. 



Now that the analysis of air — physical and chemical — is attract- 

 ing so much attention, it may be of seme interest to know what 



