139 



The apparatus is of a convenient construction for the purposes de- 

 signated in the title of the paper. The lower electrode or cathode is 

 a parallelopipedon of charcoal, on which the body is placed, to be sub- 

 jected to the influence of one or more batteries; and tubes, with valve- 

 cocks, communicating with an air-pump, a barometer-gauge, and a 

 reservoir of hydrogen, open into the interior of a ground plate, on 

 which a bell-glass is fitted, air tight. In the experiments of the 

 author, an equivalent of lime was heated with one equivalent and a 

 half of bicyanide of mercury, in a porcelain crucible, enclosed in 

 the alembic made for this purpose, and described in a former paper. 

 (See p. 131 of these Proceedings.) The weight of the residue was 

 such as would result from the union of an equivalent of calcium with 

 an equivalent of cyanogen. This was then subjected to galvanic 

 action on the cathode of the apparatus, the anode being brought in 

 contact with it, and the result was the production of masses on the 

 charcoal, having a metallic appearance. 



Phosphuret of calcium, exposed in the same manner, in the gal- 

 vanic circuit, left pulverulent matter which effervesced in water, and, 

 when rubbed on porcelain, appeared to contain metallic spangles, 

 which were rapidly oxidized in the air. 



In one experiment, particles of charcoal, apparently fused or re- 

 sembling plumbago, dropped from the anode. 



After heating lime with bicyanide of mercury, the mass was dis- 

 solved in acetic acid, in which nitrate of mercury produced a copious 

 white precipitate, that detonated under the hammer like fulminating 

 silver. 



Doctor Coates announced the formation of the Pathological 

 Society of this City, and adverted to some of its labours. 



Doctor Hare made some observations on the method of ob- 

 taining oxygen from nitre. 



He stated that the usual opinion of chemists, that the residuum is a 

 hyponitrite in case the process is stopped during the extrication of 

 pure oxygen, is erroneous ; as he found that it always contained, under 

 these circumstances, a considerable portion of undecomposed nitre. 

 If the heat was pushed in order fully to change the nitre into hypo- 

 nitrite, there was always an extrication of nitrogen. 





