1838.] Topographical Report on the N'eilgherries. 93 



maintains that equal warmth of the surface, which is so necessary to 

 health. It preserves the sick and the valetudinarian from the severe 

 cold, of the ill effects of which they are so susceptible, and serves to 

 maintain that moisture of the skin, which is checked, almost to sup- 

 pression, by the rapid transition from the great heat of the plains to 

 the cold of the mountains. It is owing principally, if not solely, to 

 this cause, that hepatic complaints so frequently deteriorate; the re- 

 pulsion of the fluids from the smaller vessels and capillaries, forcing 

 them inwards, and producing congestion, which has a tendency to in- 

 flammation of the parenchyma, and the formation of abscess, espe= 

 cially vvhere there has been inflammation of that organ, or a tendency 

 to it in the low country. The same check to perspiration sometimes 

 produces ephemeral fever, to which even those who reside are subjectj 

 more or less, accovding to their attention to clothing, of which the 

 chief point is flannel in contact with the skin, as generally and uni- 

 formly as possible, the comfort and benefit of which no outward co- 

 vering can supply. 



The highest degree to which the thermometer rises is to be found 

 at the sun's declension, about half past two p. m. when it often is as 

 high as ninety degrees of Fahrenheit, on walls which reflect the heat, 

 although from the freshness of the breeze it gives no such impression 

 to the feelings, unless the person be in a position where radiation is 

 interrupted by houses or other objects. The lowest degree of tempe- 

 rature yet observed is sixteen of Fahrenheit, or sixteen degrees below 

 the freezing point. Both these extremes may occur in the same twen- 

 ty-four hours, if the atmosphere be perfectly clear and dry and no 

 cloud visible, under which circumstances the cold will be great, be- 

 cause radiation is unimpeded; and in the valleys, therefore, the tem- 

 perature is at the lowest, of which there can be little doubt, as was 

 lately expeiienced in a tent near Makoruty peak in the Koondah, in 

 which the water in a tumbler on a table, inside the tent, was converted 

 into a mass of ice, and the mercury in the thermometer which 

 was hanging on the tent pole fell to 20 of Fahrenheit; so that 

 outside, and in a still lower situation, it most probably would have 

 fallen four or five- degrees below that. A question has been 

 raised as to the reason of this. I should say that, in the first 

 '] place, on the withdrawal of the sun's rays, the heated air from 

 ! the valleys ascends, and the moist and cold air falls into them; 

 that, therefore,' below, the air is sensibly colder, and also con- 

 tains much more moisture, which humidity is very favourable to the 

 further abstraction of caloric ; while it is also less disturbed than the 



