312 THE LABRADOR PENINSULA. CHAF. xvm. 



Canada ; but he has conceived the idea of combining the 

 fish-offal with a large amount of calcined shale, under the 

 impression that the manure thus prepared will have the 

 effect of driving away insects from the plants to which 

 it is applied. He employs a black bituminous shale from 

 Port Daniel, and, distilling this at a red heat, passes the 

 disengaged vapours into a vat containing the fish, which by 

 a gentle and continued heat have been reduced to a pulpy 

 mass. The calcined shale is then ground to powder and 

 mingled with the fish, and the whole dried. Experiments 

 made with this manure appear to have given very satisfac- 

 tory results, and it is said to have had the effect of driving 

 away insects when applied to growing crops - - a result 

 which may be due to the small amount of bituminous 

 matter in the products of the distillation of the shale, rather 

 than to the admixture of the calcined residue. Coal-tar is 

 known to be an efficient agent for the destruction of 

 insects ; and in a recent number of the journal " Le 

 Cosmos " it is stated that simply painting the wood-work 

 of the inside of green-houses with coal-tar has the effect 

 of expelling from, them all noxious insects. Mr. Bruce 

 caused several analyses of this shale to be made by 

 Mr. Eeid of New York, from which it appears that 

 different specimens contain from 2'0 to 26'0 per cent, of 

 carbonate of lime, besides from 1*4 to 2'0 per cent, of 

 gypsum, 2'0 per cent, of iron pyrites, and from 4 '5 to 6 '7 

 per cent, of carbon remaining after distillation. The 

 amount of volatile matter, described by Dr. Eeid as 

 consisting of water, naphtha, and ammonia, was found by 

 him in two different samples to equal only 3-5 per cent., 

 of which a large proportion is probably water. 



