NO. I AIR AND TUBERCULOSIS — HINSDALE 39 



common factor present in all cases where a fall was noted was the 

 segregation of the patients in hospitals or sanatoria. In each country 

 where the institutional has replaced the domestic relief of destitu- 

 tion there has been a reduction of the death rate from phthisis which 

 is roughly proportional to the change. 



As to the cause, then, of the spread of tuberculosis, we shall find 

 that it probably always lies in ignorance, indifference and other moral 

 or sociologic causes, and, in many of the cases cited, not to climatic 

 or atmospheric conditions. 



Our opinion of sea air is fortunately not confined to that of the 

 high seas or even that of islands. The sea air sweeps the mainland 

 and, as we know, modifies the climate of all adjacent portions of the 

 Continent. The great source of atmospheric moisture is found ulti- 

 mately in the oceans. The invisible watery vapor and the visible 

 clouds are carried inland and deposit their water over the Continent. 

 The monsoons which are most highly developed in India and other 

 parts of Asia, prevail also in Texas and on the Pacific coast of the 

 United States. These seasonal winds are of great importance from 

 a climatic standpoint and hence should be taken into account in ref- 

 erence to the climatic treatment of tuberculosis.^ During the sum- 

 mer and autumn in India these seasonal winds sweep inland from the 

 sea and deluge the country with rain. This amounts, in the Khasi 

 Hills, 200 miles north of the Bay of Bengal, to between 500 and 600 

 inches a year and reaches its maximum at points about 1,400 meters, 

 4,600 feet, above sea level. 



Fortunately in the United States these seasonal winds, while pres- 

 ent, are not so dominant as climatic factors. We are more concerned 

 in the present study with the diurnal winds of the seashore. The sea 

 breeze which tempers the heat of our coasts is a distinctly beneficial 

 feature of the shore and not only tends to moderate the heat of 

 the summer day, but sweeps inland for fifty or a hundred miles the 

 pure ocean air and provides all the desirable features of a marine 

 climate. 



ARCTIC CLIMATE 



Passing still farther north we have the Arctic climate. It is 

 marine or insular and cold. Arctic voyages have been proposed for 

 the treatment of tuberculosis and, as adjuncts to the voyage, a sum- 

 mer sojourn in the northern fjords -of Greenland. A trip of this 



^ See William Gordon : The Influence of Strong, Rainbearing Winds on 

 the Prevalence of Phthisis, H. K. Lewis, London, 1910, Observations in 

 Devonshire. 



