June, '10] HOWARD : AFRICAN LOCUST PROBLEM 267 



breaking his fast. Consequently all the efforts at actual destruction 

 were centered on the voetgangers. At first the various methods sug- 

 gested in the locust reports of the United States of America, Egypt, 

 Cyprus, and Argentine, were tried, from the digging of eggs to the 

 use of rollers, trenches or screens and pits, to that of the famous locust 

 fungus. All were found ineffective, owing to conditions existing in 

 South Africa. The population is very sparse, labor is scarce and ex- 

 pensive and transportation and materials are very costly. Moreover 

 these methods were not thorough and could not be carried out over 

 wide areas except at great expense to the Government and the people 

 were not yet broad minded enough to take up the work on their own 

 initiative. The old Boer was indolent enough to accept a locust 

 plague as a punishment for his sins and resorted to prayers and days 

 of fasting, like our half-civilized ancestors of the middle ages, in the 

 hopes of seeing a miracle wipe them out. 



It remained for Natal to devise a method of voetganger destruction 

 which is remarkable for its simplicity, cheapness and ease of applica- 

 tion. The history of this discovery is interesting. 



The sugar planters in Natal found the locusts very troublesome 

 about 1894. They tried every method of destruction and amongst 

 others the pit and screen system. The hoppers were driven into the 

 trenches which were about two feet deep and in the bottom of which 

 was placed four to six inches of treacle, a waste product from the 

 sugar mills. The treacle held and smothered the hoppers. But it 

 was soon noticed that when the trenches were filled with earth some 

 treacle oozed out and the survivors hung about and ate the treacle 

 and that fresh swarms seemed to be attracted to the treacle and ate 

 it. They then tried poisoning the treacle and found arsenic the best 

 poison. The next step was the use of a bait made of boiled sweet po- 

 tatoes, molasses and arsenic, but this soon gave place to poisoned 

 molasses sprinkled about on the grass. The credit for the discovery 

 so far belongs to Mr. Gilbert Wilkinson a sugar planter of Natal. 

 This method was followed for some time with considerable success. 

 Later, I believe, at the suggestion of Mr. Lounsbury, the treacle and 

 poison were made into a thin solution and sprayed on the grass and 

 vegetation. This sweetened arsenical-spray is what has revolutionized 

 the whole work of locust destruction in South Africa, because of its 

 simplicity in mixing and applying and its complete effectiveness. 

 The formula for its use vary with the size of the hoppers to be killed 

 and the urgency of killing them. The usual strength employed is 1 

 lb. of arsenite of soda and 2 lbs. of crude sugar or molasses to 16 gal- 

 lons of water but in special cases it may be made as strong as 1 lb. 



