204 Miscellanies. 
gold, platinum and palladium under certain circumstances, produce this 
change, it being facilitated by the access of air. The experiment is 
easily made by placing a piece of antimony, zinc, bismuth, lead or tin, 
in a solution of the salt in question, when it soon acquires the property 
of forming a blue precipitate with the persalts of iron, due to the forma- 
tion of the ferrocyanide of potassium. A simple manner of demonstra- 
ting the same fact consists in conveying a drop of the liquid to a bright 
surface of one of the metals, and adding a drop of a solution of nitrate of 
iron, when immediately after the mixture has taken place the metal be- 
comes coated with a layer of prussian blue. On gold, platinum, and pal- 
ladium,. this change takes place but very slowly. Other substances be- 
sides the metals produce it, as phosphorus—hydrogen in the nascent state, 
as when disengaged by the agency of electricity from a plate in the solu- 
tion. Hydrogen when combined with sulphur, selenium, phosphorus, 
arsenic, antimony, and tellurium, will do the same even in the gaseous 
state. Sugar produces the change when boiled with a solution of the 
salt; also uric acid and creosote. All the bodies that decompose the 
ferridcyanide are found also to reduce the persalts of iron to the state of 
the protosalts. And it may be as well to mention here that J. Stenhouse 
(Chem. Soc. Mem. Vol. 2, p. 121) has ascertained that fresh grass and 
other green vegetable matter, peat, and wood coal, have the same effect 
upon the persalts of iron, 
_ Decay and Mouldering of Wood, by M. Hermann, (Jour. fiir Prakt. 
Chim. Vol. 37, p. 165, and Chem. Gaz. Oct. 1844, p. 423.)—It is shown 
in these investigations that wood in its decay undergoes two entirely dif 
ferent processes, during which both oxygen and nitrogen are absorbed, 
and nitroline and humus are formed, the latter succeeding the former; 
-by bumus is here meant all parts of rotten wood soluble in alkalies. 
From 1 atom wood=C** H?2 022, 4 atoms water, 4 atoms carbonic 
acid, and 1 atom nitroline, can be focived by the absorption of 4 atoms 
oxygen and | atom nitrogen. M. Hermann shows that decayed wood 
contains three distinct organic substances—nitroline, ligneo-humous acid, 
and humus. One kind of nitroline gave— 
es ; ‘ ? 
’ 571 
H 1 a 60 
oO 1 « 32:9 
Nit.?, y 40 
100°0 
Decomposition farther 
Fresh decomposed wood, advanced. ? 
Nitroline, ee i 188 
Ligneochumic anid ; : 210 : : 53°6 
Humus, . 175 : “ 26.6 walk 
Ammonia, epee OS es 10 
