150 Jntelligence and Miscellaneous Articles. 



iron is completely converted into oxide and deposited. The deposit 

 of the spring itself may also be taken. These deposits are dissolved 

 in muriatic acid, and evaporated to a certain degree for the removal 

 of the glucina, titanium, sand and silica, when the solution generally 

 contains only alumina, lime, magnesia, iron, manganese, nickel and 

 cobalt. 



To this solution carbonate of soda is again added until a precipi- 

 tate is obtained, which is agitated in the air with a large quantity of 

 water. It is then washed ; and when it has become oxidized in the 

 air, it is brought into contact with water which has been saturated 

 with carbonic acid in an apparatus fitted for the purpose. This 

 dissolves only the carbonates of nickel and cobalt, upon which sul- 

 phuretted hydrogen is passed through the solution, or hydrosul- 

 phuret of sodium added to it. 



By this means the nickel and cobalt are separated, generally very 

 slowly, in the form of sulphurets. The sulphurets are dissolved in 

 nitromuriatic acid, precipitated by carbonate of soda, and treated in 

 the manner proposed by Laugier for the detection of cobalt and 

 mckeX.—Journ. de Pharm. et de Chim., 3rd ser. xxiv. p. 305. 



ON THE INrLUENCE OF PRESSURE UPON THE FORMATION OF 

 CHEMICAL COMPOUNDS. BY PROF. WOHLER. 



Hydrate of chlorine, which is immediately decomposed at ordi- 

 nary temperatures and at the pressure of the atmosphere, remains 

 for the most part undecomposed even at a summer heat when en- 

 closed in hermetically-sealed tubes, under the pressure of the chlo- 

 rine which is set free from a portion of it which undergoes decom- 

 position. In such a tube, when plunged into water of a temperature 

 of 86°-10+° F., the hydrate of chlorine is decomposed, but becomes 

 partially restored on its return to the ordinary tnnperature. 



This decomposition is not prevented by the exclusion of the air 

 under the pressure of chlorine gas of the tension of the atmosphere ; 

 under these circumstances the decomposition takes place as usual at 

 any temperature above 32° F. 



A tube in which hydrate of chlorine was hermetically sealed was 

 exposed to the sun for a whole summer's day. It became Huid, but 

 did not indicate decomposition of the water by the setting free of 

 oxygen. 



The author had already observed, that during the preparation of 

 liquid sulphuretted hydrogen from sulphuret of hydrogen in her- 

 metically-sealed tubes, colourless crystals are sometimes formed, 

 which immediately disappear on the tube being opened. 



In two tubes, in which sulphur, but no liquid sulphuretted hy- 

 drogen had separated, these crystals were formed in large quantity ; 

 thev did not however make their appearance in a third tube, in 

 which the persulphuret of hydrogen was enclosed together with con- 

 centrated muriatic acid. Hence the author concludes, that the cry- 



