INTRODUCTION. xxiii 
the corps, when unprovided with the necessary defence, have had our ears swelled 
to two or three times their natural size, and the line of our hats marked, all round, 
by the trickling blood. It was often necessary to rise many times, in the course of 
the night, to allay the fever of the head, by repeated cold bathings; and, at some 
of the worst spots, we could scarcely have discharged our ordinary professional. 
duties at all, without the constant protection of musquito-netting, worn over our 
head and face. 
The health, even of the more marshy portions of the District, seems better than, 
from its appearance, one might expect. The long, bracing winters of these northern 
latitudes exclude many of the diseases, which, under the prolonged heat of a more 
southern climate, the miasm of the swamp engenders. Perhaps the healthiest por- 
tion of the whole District, is along its northern limit, where it is coterminous to the 
British dominions. At the Pembina settlement, owned by the Hudson’s Bay Com- 
pany, to a population of five thousand there was but a single physician; and he 
told me, that, without an additional salary allowed him by the Company, the 
diseases of the settlement would not afford him a living. 
Our own party occasionally suffered severely from sickness, consequent upon ex- 
posure amidst almost impassable swamps. In 1849, not a single member of my 
corps escaped obstinate intermittents. In 1848, Dr. Shumard was attacked with a 
severe pleurisy, high up on the St. Peter's, beyond the reach of all medical aid. His 
life being in great danger, he was received, for a few days, into the mission house, 
at Traverse des Sioux, where the missionary, Mr. Hopkins, gave up to him his bed, 
and treated him with the utmost kindness. He was then run down the river, day 
and night, in a canoe, to Fort Snelling, where Captain Eastman, of the U. S. Army, 
stationed at the fort, assigned to him, during his illness, apartments in his own 
quarters. To the hospitable care of these two gentlemen and their families, Dr. 
Shumard probably owes his life; and I take pleasure here, in tendering to them, on 
his behalf, his most grateful acknowledgments. 
Mr. B. C. Macy, in tracing the confines of the carboniferous formation between 
the Iowa and Cedar Rivers, penetrated a region of ponds and swamps, through which 
he waded, under a burning July sun, for many days, and contracted an obstinate 
and dangerous intermittent, from the effects of which his health, even now, after 
two years, has scarcely recovered. 
We lost, by death, but one man, of cholera, at Muscatine, in Iowa, in J uly, 1849. 
Throughout the whole of that season, as the cholera was very prevalent over the 
region of country we were surveying, we had great difficulties in inducing voyageurs 
to risk the exposure of our trips, and had to offer extra pay, in order to obtain their 
services at all. Gobert, the man we lost, was attacked while we were getting our 
goods into the warehouse at Muscatine, about one o'clock in the day. We could 
not persuade the tavern-keeper to receive him into his house ; but we obtained, not 
