22 



The settlers regarded this as a heaven-sent miracle, and there 

 stands to-day at Salt Lake City a monument costing $40,000 to 

 commemorate the event. (See frontispiece.) 



Among the most persistent enemies of grasshoppers we must 

 count crows. There was a tremendous outbreak of these insects 

 in Australia in the spring of 1894. Dr. N. A. Cobb of the De- 

 partment of Agriculture, Sydney, New South Wales, tells of the 

 immense good done by crows in the Mossvale district in de- 

 stroying the pest. For weeks crows were very abundant 

 throughout this region. Dr. Cobb made an effort to estimate 

 the number. Armed with a telescope he mounted one of the 

 highest hills and found that the crows were about equally dis- 

 tributed over the land. He estimated that the Mossvale dis- 

 trict at that time was supporting not less than one-quarter of a 

 million crows, and it was his belief that the actual number was 

 much greater than this estimate. He found that the crows were 

 feeding almost entirely on grasshoppers. By examining a large 

 number of stomachs he became satisfied that each crow's 

 stomach contained at that time nearly if not quite 100 grass- 

 hoppers. He assumed that the stomach of each crow was filled 

 twice a day. (Any one who has ever attempted to keep a crow 

 from starvation will realize that this was a very moderate esti- 

 mate, and that a crow receiving only two such meals a day 

 would soon become very attenuated.) He figured that the 

 crows in that district were destroying daily a total of 25,000,000 

 grasshoppers, and as this crow invasion lasted for a month he 

 put the total number of grasshoppers destroyed in the district 

 at 750,000,000. This number reduced to tons would give a 

 total weight of 100 tons of grasshoppers. But he said that even 

 this figure failed to give a clear idea of the good work done by 

 these crows. By careful computation he arrived at thi con- 

 clusion that these 750,000,000 grasshoppers if not killed by the 

 crows would have consumed over 2,000 tons of grass and other 

 fodder. He thus came to the conclusion that through this 

 destruction of grasshoppers the crows saved thousands of tons 

 of grass and other products to the inhabitants of the Mossvale 

 district. He says, also, that a significant feature of the locust 

 plague in 1891 in the western part of New South Wales was the 



