58 



lings, and consequently of our mode of living, fully accounts for this 

 improvement. The remark of Dr. Horr, that the sanitory line is ap- 

 proaching the river at Dubuque at the rate of about fifty feet per an- 

 num, applies with greater or less force to all our towns. 



Dr. Drake's interesting and philosophical work on the diseases of 

 the Mississippi valley, shows, by a very extensive array of statistics, 

 that most of the elements of disease may abound, and localities re- 

 main comparatively healthful, because of the absence of a single one. 

 Thus our bottom lands, if transported to the latitude of New Orleans, 

 would unquestionably generate yellow fever, and other malignant 

 forms of disease, whilst, for want of a tropical sun, they with us pro- 

 duce mild intermitting or remitting fevers. 



The only remaining element of disease deserving consideration at 

 this time, is the hygrometric condition of the atmosphere, and the 

 consequent amount of rain which falls. On this subject I have no 

 records to consult, and therefore I must be very brief. The value of 

 rain as a health producing or disease engendering agent, must depend 

 on its amount, or on the time of the year at which it falls. When 

 the country is deluged at the commencement of the warm season, it 

 must be more injurious than if it fell in mid-winter. As a general 

 rule, that season is the most healthful in which the ordinary quantity 

 falls, rather than that in which there is either an excess or deficiency. 

 As trees are considered valuable in condensing or in affording those 

 vapors, which, rising into the higher regions of the atmosphere, are 

 condensed and fall down in showers, I should suppose the neighbor- 

 hood of our water courses, abounding in forests, would be more reg- 

 ularly supplied by rains than our prairies ; but I am not prepared to 

 say that this is so. 



The diseases of Iowa embrace a very extensive list. Wherever 

 man is found, the maladiec to which he is liable will also exhibit 

 themselves. But a more limited range is undoubtedly contemplated 

 by the resolution under which this report is m de. No one, for in- 

 stance, would rank apoplexy or gout among the diseases of Iowa, be- 

 cause cases of each might occur within the limits of the State. The 

 object is to ascertain what diseases our topography and climate pro- 

 duce. 



For the sake of order I will enumerate our diseases as they occur 

 in the successive seasons of the year, commencing with the spring. 

 This is the season of sudden changes of temperature, and we have 

 consequently catarrhal affections, some of the milder, and occasional- 

 ly 6ome of the severer forms of pulmonary disease, such as bronchi- 

 tis, pneumonia and pleuritis ; we have, also, Inflammatory rheumatism 



