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 strippings, 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 strippings, that the entire topography 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
- ↑ 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.