Action of Ammonia on Chlorides and Oxides of Mercury. 495 
present day, founded on facts that pneumatic chemistry, as ap- 
plied to germination, has clearly demonstrated. ‘ It is well 
known that seeds will not germinate in the light. This is 
caused by light decomposing the carbonic acid gas, expelling 
the oxygen, and fixing the carbon, whence all the parts be- 
come hardened,—a condition under which vegetation cannot 
proceed.”—Lindley’s Introd. to Bot. p. 270. 
Still we regard the author of the criticism with feelings of 
the most unfeigned respect. But when it comes to be circu- 
lated at second-hand, and advanced by the plagiarists as an 
original remark of their own, without any intimation what- 
ever of the source from which it came, we can only regard them 
with feelings of contempt. In a late botanico-veterinario- 
agricultural periodical, the criticism was excerpted from the 
work of M. DeCandolle, and published, in translation, as the 
actual critique of the editor or writer of the article, without 
the slightest reference to the original from which it was stolen. 
But as the periodical in question did not long survive the 
commission of this piece of plagiarism, and died a natural 
death (some say a violent death) at a very early age, we have 
nothing further to say on the subject. De mortuis nil nisi 
bonum. 
Charing, Kent, Feb. 17, 1836. Patrick KeiTH. 
LXXXV. Experiments on the Action of Ammonia on the Chlo- 
rides and Oxides of Mercury, and on the Composition of 
White Precipitate. By Ropert Kane, M.D., M.RI.A* 
The paper of part of which the following is an abstract was 
read to the Royal Irish Academy at the October and November 
meetings of 1835, and will appear in the next part of the Trans- 
actions of that body. By permission of the Council the present 
abstract is sent for publication in the Philosophical Magazine. 
Y the action of ammonia on a solution of corrosive subli- 
mate there is produced a White Precipitate, which has been 
frequently made the subject of examination by chemists. 
Nevertheless there prevails considerable doubt as to its real 
nature. In these countries there has been adopted a theory, 
founded principally on the experiments of Hennell, that it 
consists of an atom of red oxide of mercury united to one of 
sal ammoniac: several, other chemists, however, of equal emi- 
nence, as Soubeiran, Guibourt and George Mitscherlich, have 
each formed separate and discordant views. I trust it will be 
* Communicated by the Author. 
