Intelligence and Miscellaneous Articles. 149 



heated, readily dissolves zinc and iron. Sulphuretted hydrogen has 

 no action upon it ; but an alcoholic solution of hydrosulphate of am- 

 monia gives it a deep brown red colour. Assafcetida yields about 3 

 per cent, of this acid. 



MM. Boettger and Will found, as M. Erdmann had done, that its 

 composition is Ce H^ N^ 0\ or C^ (H^ X^) 0°-. This acid is bibasic. 

 It is capable of forming several salts with two different bases. All 

 the oxypicrates, in common with the picrutes, possess the property 

 of exploding with considerable force when heated gently. — Journ. 

 de Pharm. et de Ch., Novembre 1846. 



REDUCTION OF THE PERSALTS OF IRON BY ZINC. 



Metallic zinc reduces the persalts of iron to the state of protosalts, 

 and precipitates at the same time some metallic iron, often in the 

 state of brilliant scales. According to M. Poumarede, it is equal to 

 one-third of that which remains in solution, the reaction taking ])lace 

 according to the following equation (Fe/3=|Fe) : 

 6SFe"-l3 O* 

 or 



S6Fe3 0M + Zn6=3SFe'^0+ + 3SZn^O+ + Fe2. 



By superoxidizing the mixture of protosalts which results from a 

 first reduction, a fresh quantity of iron may be precipitated ; and by 

 successive operations, the whole of the iron of a solution may be pre- 

 cipitated. 



If weak solutions be operated upon, there is usually disengaged a 

 certain quantity of hydrogen, which, according to the author, is de- 

 rived from a secondary decomposition, operated on water by the iron 

 set free ; in fact, the zinc is always covered with a very slight coating 

 of oxide of iron. 



According to M. Poumarede, the solutions of nickel, manganese, 

 and even of alumina, yield similar results. — Jottrn. de Pharm. et de 

 Ch., Novembre 1846. 



AWARD OF MEDALS. LINNiEAN SOCIETY. 



A Special General Meeting of this Society was held on PViday the 

 8th of January, to consider the subject of the following Statement 

 and Resolution of Council relative to the Bequest of the late Edward 

 Kudge, Esq., F.L.S. 



The Council, after much patient and anxious deliberation, had 

 unanimously come to the following resolution : — 

 _ " Resolved, — That in the opinion of this Council, on a full con- 

 sideration of the terms of the bequest of the late Edward Rudge, Esq., 

 of the interest of a sum of £200, for the purpose of establishing a 

 Medal ' to be awarded by the President and Council of the (Linnajan) 

 Society, at their discretion, to the Fellow of the said Society who 

 shall write the best communication in each volume which after his 

 (the testator's) decease shall be published by the said Society, in 

 either of the four departments of Natural History,' it is inexpedient 



