472 MISS W. H. SAUNDERS ON THE 



poured into a, depression at tlie top and tlioroughly incorporated 

 with the soil by the " cone-and -quarter " method, . The mixture 

 was spread over the surface of tlie manure, forming a layer 1 inch 

 thick. 



{h) Treating the soil on which the manure rested, as well as 

 the surface, by sprinkling the plain oil or spreading oiled soil, 



(c) Sprinkling plain oil evenly over the surface of the manure. 



Afethods. 



I. Three manure-heaps, each on a, base 65 feet square, rising 

 to 3 feet in the centre, were treated with Neutral Blast-furnace 

 oil, Blast-furnace Creosote, and Green Tar oil mixed with dry 

 soil in the proportion of one part oil to 40 parts soil, spread 

 evenly over the surface, forming a layer 1 inch thick. Maggots 

 Avere put under the treated layer on the fourth day. 



Result s. 



Nexitral Blast- t,i j. j? n ^ n m r\-7 



n ^., Jilast-rurnace Creosote. Green Tar Oil. 



jnrnace Oil. ■' 



Living after 2 da^'s. Dead in 2 days. Dead in 24 hours. 



II. Four manure-heaps, each on a base 7 feet square, rising 

 3 feet to a top 3 feet square, were treated with : — 



Green oil. ~j 



Green oil and Pyridene. > 5 gallon to 10 gallons of soil. 



Nentval Hlast-furnace oil. J 



Control. 



The mixture was spread evenly over the surface. All the 

 manure was infected. 



Results. 



In three days larvae w^ere found dead in the treated heaps. In 

 six days the Control heap contained large maggots. The treated 

 heaps remained immune. 



III. Four manure-heaps, each on a base 4 feet 6 inches square, 

 rising 18 inches in the centre, were treated with: — 



1 Tr- , •, IT) -J f 3^ gall, sprinkled over base. 



1. Mineral oil and ryridene. .^ -101 



<■ \ gall, with 10 galls, soil on surface. 



2. Mineral oil and Pyridene. \ gall, with 10 galls, soil on surface only. 



3. Tar oil and Pyridene \ gall, with 10 galls, soil on surface only. 



It 



. ,.. -1 1 D ■ 1 ^ 4 ^'all- with 10 galls, soil on surface only. 



4. lar oil and Pyridene i . 



\ gall, sprinkled over base. 



The manure contained many full-grown larvse, but the heaps 

 were too small to heat. 



Results, 



Flies emerged from the mineral-oil heaps through places where 

 straw prevented the treated soil from lying evenly. They were 



