Page:Popular Science Monthly Volume 40.djvu/846

824 the same way, the deaths of the Black Hole of Calcutta add their evidence, though it is an evidence of an extreme kind. While out of the one hundred and forty-six persons shut up, one hundred and twenty-three died, of the remaining number (Carpenter, page 357) many afterward died of putrid fever—that is, were poisoned, owing to an insufficiency of oxygen to neutralize the poisons breathed out on all sides of them, and rebreathed by themselves. A much simpler piece of evidence is presented to us daily by our own eyes. Who is not struck by the pasty, anæmic look of our city children, and of the large number of those who follow sedentary occupations, as contrasted with the looks of those who live in the country and are much in the open air? What is that pasty, anæmic look? It is the absence of red corpuscles from the blood, indicating that where oxygen is deficient the red corpuscles are not produced in their proper quantity. So also the effects of living in rooms in which sewer-gas has penetrated illustrate in their own stronger degree the effects of living in unventilated rooms. The one is the lesser form, the other the more serious form of the same evil. In both, bacteria thrive and multiply, and in both, meat and milk rapidly taint. They are both full of organic matter, and the symptoms of headache and feverishness are common to both, though, of course, the case of sewer-gas is much the more acute case. Again, we all know the wonderfully restoring effect that hill air with its ozone has upon us after town life; showing how the poison has depressed all our functions, and how the pure air restores their energy. We see the same effect in the lives of work-people. Sir D. Galton, as we have seen, tells us of better work done, more energy, more appetite, when air is introduced into unhealthy work-rooms. Dr. Parkes tells the same story. Dr. A. Ransome, speaking in 1875, quotes the case of the Guards, picked men, highly cared for, yet who died quite as fast as the civil population. Why? he asks. Mainly from defective ventilation of the barracks (Health Lectures, 1875-'78, page 150).