in the Butter of Nutmegs. 109 



rvtes In the second also 54-95 is expressed by the analysis, 

 but 2-14 being added for the carbon retained by 25-97 barytes, 

 frives the number stated above. 



The mean of the two analyses makes the quantity of bai-ytes 

 contained in the salt 25 93 per cent. : the quantity found by 



calculation is 25-62. i u i ui 



Scricate of Silver.— Thh salt may be prepared by double 

 decomposition in the same manner as sericate oi barytes. 



When it is newly precipitated, it is a bulky white powder, 

 which speedily acquires a lilac colour by exposure to light. 

 To avoid this it must be washed in the dark. It is insoluble 

 in water, but very soluble in a solution of caustic ammonia, 

 from which it may be obtained, by spontaneous evaporation, 

 in lar^re transparent colourless crystals. It melts upon the 

 application of heat, but at the same time undergoes decom- 



I. 0-36] gramme of substance, burned with oxide of cop- 

 per,' gave 0-2G7 water, and 0-646 carbonic acid, 



n. 0-340 gramme of substance, burned with oxide of cop- 

 per,'"'ave 0-610 carbonic acid, and 0-243 water. 



HI? 0-553 gramme of substance, burned with oxide of cop- 

 per, "ave 0-992 carbonic acid, and 0-4015 water. 



0-?04 gramme of salt left, after ignition, 0-277 metallic 



silver. 



I. II. in. 



Carbon 49-48 49-61 49-60 



Hydrogen 8-03 7-94 8-06 



Oxygen 7-82 7-78 7-67 



Oxide of silver 34-67 34-67 34-67 



100-00 100-00 100-00 



If we suppose the salt to be composed like that of barytes 

 of one atom of sericic acid and one atom of oxide of silver, 

 then the numbers given below should represent the analysis. 



By calculation. 



28 Carbon 2140-18 50-61 



27 Hydrogen 336-94 7*94 



3 Oxygen 300-00 7-13 



1 Oxide of silver 1451-61 34-32 



4228-73 100-00 



The difference between the carbon found by analysis and 

 calculation is very considerable, but the close correspondence 

 between the hydrogen and the oxide of silver leave little doubt 

 that the formula is the same as that of the salt of barytes. At the 

 same time it is proper to mention that the close correspond- 



