THE TYPHOID FLY 137 



THE TYPHOID FLY ON THE MINNESOTA IRON RANGE 1 



By Professor F. L. WASHBURN 



AGRICULTURAL EXPERIMENT STATION, ST. ANTHONY PARK, MINN. 



TOWARD the northern part of Minnesota, running from a point 

 near Coleraine and Hibbing on the west to Ely on the east, is 

 a low ridge of land, on an average about 1,200 feet above seal level, 

 known, as most of you are aware, as the Minnesota Iron Range. It is 

 not out of place to say that the industries associated with iron mining 

 on this range give employment to over 200,000 people, all told, and of 

 this number about 16,000, represented by Finns, Austrians (in the 

 broadest sense of that term), Italians and a few Swedes, labor day and 

 night to bring to the surface and send to Duluth, in carloads, the iron 

 ore which enriches the coffers of the United States Steel Company. 

 These latter are the miners, the actual workers with pick and shovel, 

 and it is of these and their environment, and their relations to the 

 common house fly of which we wish to speak. 



I used the expression " bring to the surface." Let me hasten to 

 say that a very large proportion of this mining is surface mining, and 

 the mines are, for the most part, particularly in the Hibbing district, 

 huge open valleys, made by stripping the surface covering the ore for a 

 depth varying from fourteen to one hundred and fifty feet. Below this 

 stripping there may be anywhere from fifty to two hundred feet of ore, 

 and the removal of this, and the shippings, leaves enormous holes, 

 resembling huge craters of extinct volcanoes. So deep are some of 

 these artificial canyons, and so tremendous the mountainous piles of 

 gravel and sand which constitute the shippings, that the entire topog- 

 raphy of that part of the country is being strikingly changed, and one 

 would imagine the phenomenon there observed to be the result of a 

 mighty convulsion, or of several convulsions of the earth's crust, did 

 lie not see, far below him, as he stands on the edge of one of these 

 mines, countless men at work, and busy engines, steam shovels and 

 trains of ore cars running on temporary tracks, either carrying off the 

 strippings, or bringing up the precious ore, which is soon speeding on 

 its way to Duluth. 



I have emphasized the fact of the existence of open mines in order 

 to make it clear that these men are working in the open air, and under 

 conditions which should be, other things being equal, in the highest 



1 Address, illustrated by lantern slide and moving pictures, delivered under 

 the auspices of the Entomological Society of America, at their winter meeting 

 in Minneapolis, December 28, 1910. 



VOL. LXXIX. — 10. 



