WATER AND MALARIAL GERMS. 273 



through ravines among* hills, where malaria is known 

 to be rife, may be, and is, carried down to the jungle 

 belt extending along the base of the mountain range 

 in a contaminated and most dangerous condition and 

 if so, it follows that the subsoil in these jungle districts, 

 which is usually water-soaked (though the surface may 

 appear to be for the most part dry), is almost always 

 surcharged with these malarial germs, whose deadly 

 exhalations render a night passed by Europeans in 

 such localities, at certain seasons, almost sure to be 

 followed by a severe attack of malarial disease'. The 

 death of Lady Canning, wife of the celebrated Lord 

 Canning, first viceroy of India, from malarial fever, 

 after only one night passed in the Terai on her way 

 down to Calcutta from Darjeeling, furnishes a sad, but 

 remarkable instance in point. We may add that the 

 most dangerous times for crossing malarious tracts of 

 this description, are the first day or two of the rains, 

 after a long drought: because the sudden descent of 

 what are most generally torrential rains, mechanically 

 displaces and causes an overflow of the malarial germs, 

 till then lying dormant in the subsoil; but above all, 

 when the country is drying up, for some time after 

 the cessation of the rains : malarious districts are at this 

 period of the year hot-beds of fever and disease. The 

 safest period for crossing such places is during the 

 latter part of the dry season, because the surface of 

 the ground, except in sandy tracts, is then generally 

 hardened by the sun into a substance resembling sun- 

 dried brick, which forms a crust, to a great extent 

 impervious to the passage of malaria. Such at least 

 is our belief, but the state of knowledge upon such 

 matters is thus far, as we have already explained, very 

 VOL. I. 1 8 



