330 Description of an Improved Rain Gage. 



height, in inches &,c. Enter the table a second time with 

 the difference and take the nearest less number to ?/, to- 

 gether with its correspondent height, which subtract from 

 the difference, and with the remainder enter the table again 

 if necessary, thus, 



Wt. of water in grains. Cor- 

 resp't 

 height, 

 the nearest number in the table, le§s than 142406.25, 

 which must be subtacted, is - - 126262.5 500 



difference - - - 16143.75 



The next number in the table, less than 



the difference, is - - - 15151.5 0.60 



which, when subtracted, leaves the re- 

 mainder 992.2£> 



the nearest number corresponding to the 



rem. in the table is - - - 1010.1 0.04 



The sum of the corresponding heights gives — Inches 3.64 



It is obviously not necessary to be restricted to either the 

 form, or the size of the above described gage. If the cy- 

 lindrical form be thought to possess any advantages over 

 that of a square prism, it is easy to find the diameter of a 

 circle whose area shall be equal to one hundred square 



inches, by the well known rule, viz. d=\/ , 



^ . ' ^ .7354 



where d represents the diameter, a, the area, and .7854 the 

 area of a circle, whose diameter is unity. If any other size 

 should be thought more convenient, as for instance, one whose 

 area is only half of that of the above described gage, the 

 same rule, if cylindrical, will give the corresponding di- 

 ameter, or if a square mouthed one be preferred, the 

 side of the square is obtained by extracting the square root 

 of fifty. But it must be remembered that whatever rela- 

 tion the area, we pitch upon, may bear to one hundred 

 square inches, the same relation will subsist between the fi- 



