358 Mr. George Harry Jackson, 



100 grs. of water, at 60° F., dissolve 23 grs. The solu- 

 tion of the salt precipitates a salt of lead, white, perfectly 

 soluble in an excess of the precipitants ; if added to a proto- 

 salt of iron, an orange-coloured precipitate takes place, 

 which is evidently the proto- cyanuret. of iron; for, on expo- 

 sure to the air, it is readily converted into Prussian blue; 

 if added to a salt of lime, a white precipitate falls which 

 is insoluble in an excess of the precipitant ; if added to solu- 

 tions of chloride of manganese, tartar emetic, or arsenious 

 acid, no precipitates take place : This salt is slightly soluble 

 in alcohol. 



II. Hydrargyro-cyanwet of sodium crystallizes from its 

 solution in white, transparent octohedrons. 



10 grs. of this salt were put into a small tube connected 

 with another containing chloride of calcium, when the same 

 process was employed as I have already mentioned under 

 the preceding salt for ascertaining the water of crystalliza- 

 tion ; the difference between the weight of the tube contain- 

 ing the chloride of calcium, before and after the experiment, 

 was 1*2 grs. of water = 8 equivalents of water of crystal- 

 lization. 



The decomposed salt remaining ill the tube after the above 

 experiment, was heated with muriatic acid ; the solution of 

 chloride of sodium obtained by this means was filtered, and 

 the filter well washed ; the solution and washings were 

 evaporated very low, a small quantity of sulphuric acid was 

 then added, and the whole evaporated to dryness in a 

 weighed platinum crucible, and ignited, the same precau- 

 tions being observed as were used in the preceding salt to 

 prevent any bi-sidphate from being present ; the weight of 

 the sulphate of soda was 1*10 grs. = 0*77 grs. of cyanuret 

 of sodium = 1 equivalent. 



10 grs. of this salt (in crystals) were dissolved in water, 

 and sulphuret of sodium was added to the solution, in the 

 same manner as in the preceding salt; the bi-sulphuret of 

 mercury thus obtained, after being well washed and dried 

 on a weighed filter, weighed 7-03 grs. = 8 - 02 grs. of bi- 

 cyanuret of mercury = 2 equivalents. 



The filtered solution, consisting merely of cyanuret of 

 sodium, was mixed with nitrate of silver, so that the whole 

 of the cyanogen was precipitated as cyanuret of silver, 



