GAS LIME. 



There has been some enquiry of late in regard to the 

 virtues of gas lime for manure. As it can be readily ob- 

 tained in the neighborhood of gas works, there is a dispo- 

 sition among the farmers to apply it to their land in the 

 expectation of great advantage to their crops. It is well 

 to consider before making a very extensive use of it. In • 

 looking up the matter, we find in the American Field Book 

 of Manures the following account of it : 



'' The refuse lime of gas works consists principally of a 

 mixture of carbonate of lime, with a variable quantity of 

 gypsum and other salts of lime containing sulphur, and a 

 little coal tar and free sulphur, the whole being slightly 

 colored by Prussian blue, the chief difference of composition 

 arising from the kind of coal employed in the manufacture 

 of gas. The following table exhibits the composition of 

 two gas limes, as analysed by Professor Johnson, one from 

 Edinburgh gas works, and the other from those of London. 

 The first two columns show what they contained when first 

 received from the works, and the second two what they 

 would have become after long exposure to the air, after 

 being made into compost, or thoroughly incorporated in the 

 soil: 



Water and coal tar, 



Carbonate of lime, 



Hydrate of lime, (caustic) 



Sulphite of lime, (gypsum) 



Sulphite and hyposulphite of lime, 



Sulphuret of calcium, 



Sulphur, 



Prussian blue, 



Alumina and oxide of iron, 



Insoluble matter, (sand, &c.,) 



