PHYSICS OF THE GLOBE. 89 



ing address, in which he takes the advanced position to 

 which all recent researches are unmistakably pointing, viz., 

 that moisture and temperature and barometric pressure are 

 for many diseases, such as consumption, yellow fever, etc., 

 not the important factors to be considered by medical men 

 in locating sanitariums, but that, on the contrary, these are 

 but incidental to the more important question, " Is the air 

 of the locality free from injurious organic dusts and germs?" 

 He says, "The term 'climatic,' which we have thus far im- 

 agined to refer to some indefinite specific concerning which 

 we could give no account, is become exceedingly clear and 

 simple ; it means, above all, air which is pure, containing no 

 miasma, no organic or inorganic mixture, in which, therefore, 

 rain or snow occurs" frequently enough to continually keep 

 it washed and pure. If meteorologists would contribute to 

 our knowledge of the sanitary relations of the atmosphere, 

 they must also observe the organic dust floating therein ac- 

 cording to the methods that are now well understood by 

 microscopists. 



The influence of high altitudes, or rather of diminished at- 

 mospheric pressure, upon health, and especially its curative 

 influence in diseases of the lungs, has received an increasing 

 amount of attention. Comprehensive memoirs upon this 

 subject have been published by Denison, of Denver, Col- 

 orado, and Gleitsmann, of North Carolina. The volume 

 by Dr. Bert on "Atmospheric Pressure and Animal Life" 

 (Paris, 1876) seems to have turned attention strongly to 

 this matter. 



The general influence of climate on consumption was the 

 subject of a Lettsomian lecture by C. T. Williams. 



CLIMATE AND GEOLOGY. 



The sreneral relations between the condition of the surface 

 of the earth and atmospheric conditions, especially the w T inds, 

 is elaborately treated of by Czerny in " Die Wirkung des 

 Windes," etc., in Petermann's Geographische Mittheilungen 

 Ero-anzumxsheft 48. Most remarkable, however, is the view 

 ably defended by Richthofen, that the immense "loess" de- 

 posit of China is the result of subaerial denudation. 



From his experiments on the capillarity of soils, Klenze finds 

 that with earths of the same degree of comminution the com- 

 position is of importance ; thus quartz conducts faster than 



