240 On the Climate of Nagpur. [May, 
have been so situated that I have either not had sufficient: leisure to 
make a regular series of observations on the latter, or those instru- 
ments in my possession have not been sufficiently correct to allow me 
to depend much upon them. This you will at once observe from the 
circumstance of my barometrical inquiries being made on the sympie- 
someter, in the accompanying table ; and you will perceive that the in- 
strument I have, which was received here apparently in good order, in 
the month of January, 1831, from England, has become liable to the 
objections made to it, by yourself, in the 15th volume of the Asiatic 
Researches*, and this to such a degree, that Iam doubtful whether you 
can make any use of the results which I now send you. They fully 
bear out however your own observations. In Europe, it appears, the 
instrument is conceived to rise in its indications, instead of lowering, as 
with us, at least if I may judge from a note made in the 10th volume of 
Brewster’s Journal of Science; although, by the bye, the remark israther 
obscure. With respect to the hygrometer used by me, it is one upon 
Kater’s plan of the oubina grasst, made by Rosrnson, in Devonshire 
Street, which is convenient from the facilities of ascertaining its indi- 
cations. Its extreme dryness is 0, extreme moisture 9.05, and the 
state of the atmosphere is at once shown from the index on the top of 
the instrument. By some trials made with DaniE.u’s hygrometer, 1.64 
of Kater was equal to 31 degrees of dryness, and 1.96 of the former to 
26 of dryness, and 3.69 to 10 degrees, as indicated by the dew-point 
on Danreti}. You will perceive that I have not made my observations 
at the extremes of the diurnal changes in the atmosphere; but as I have 
already said, I have been in the habits chiefly of noting the state of 
my instrument more as explanatory of the appearances on the sky, 
than with other objects, and have accordingly chosen the periods which 
were most convenient to myself, for recording their indications. The 
state of the seasons, as extracted from my medical reports, will explain 
some points regarding the thermometer, and the quantity of rain given 
is that observed to have fallen at Nagpur at the distance of nine miles 
of this place, and which was recorded by Dr. Wruuiz, late Residency 
Surgeon there. 
* Vide also GLEANINGS IN SCIENCE, i. 201. 
t+ (Andropogon contortum.) 
t As the temperature, at which these comparisons were made, is not mentioned, 
it is impossible to form a correct scale for KATER’s hygrometer : the safest plan will 
be to assume that equal increments denote nearly equal accessions of aqueous ten- 
sion ; 9.05 being 100 or extreme moisture, each indication may be divided by 9 to 
find the tension roughly.—Ep. 
