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* VIII. — On Rain Guages and Registry of River Freshes, 



To the Editors of the Madras Journal of Literature and Science, 

 Dear Sirs, — I beg the favour of your inserting the ac- 

 companying Memoranda in your forthcoming number, not so 

 much on account of their own value as because they may 

 serve to attract attention to a subject which, I think all will 

 agree, is of much interest and importance. The table A of 

 the heights to which some of the chief rivers of the Presidency 

 have risen at different dates, although incomplete, is, I be- 

 lieve, accurate as far as it goes. In future numbers, I hope 

 to be able to supply information of the same kind in which 

 there will be fewer deficiencies. The drawing and Estimate 

 for a cistern rain guage are intended to shew how cheaply 

 and easily one may be constructed of brick and mortar, and 

 of a form so simple that observations of the depth of rain may 

 be made and accurately registered by unscientific natives. — 

 No doubt, most of your readers are acquainted with more 

 perfect kinds of pluviometer, but I shall be excused for oc- 

 cupying this space amc-ng your pages with the description of 

 so rude a contrivance, should my doing so be the means of 

 inducing any of them to procure and publish information 

 which but for some hint of the kind, we could hardly expect 

 to obtain. 



We are all in the habit of talking and hearing much about 

 the N. E. and S. W. Monsoons, and we have general ideas 

 on the subject of their duration and violence and of the ex- 

 tent of country over which each has influence, but their phe- 

 nomena are by no means thoroughly understood. We can 

 neither distinctly and correctly trace the line which separates 

 the tract watered by the one from that which chiefly benefits 

 by the other, nor can we yet shew by what gradations the 

 quantity of rain which at Bombay averages 84 inches per 

 annum is diminished as we cross the Peninsula to 50 inches, 



