330 Description of an Improved Rain Gage. 
height, in inches &c. Enter the table a second time with 
the difference and take the nearest /ess number to ¢f, 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- 
ree resp’t 
en height. 
the nearest number in the table, less than 142406.25, 
- 126262.5 500 
which must be subtacted,is - 
difference ~ - - 16146.75 
The next number in the table, less than 
the difference, is - . - 
15151.5 0.60 
which, when subtracted, leaves the re- 
mainder - ‘2 - *, . 992,25 
the nearest number corresponding to the ae 
rem. in the table is - < - $010.1 0.04 
The sum of the corresponding heights gives—Inches 5.64 
It is obviously not necessary to be restricted to either the 
form, or the size of the above described gage. If the cy- 
lindrieal form be thought to possess any advantages over 
that of a square prism, it is easy to find the diameter 0 ? 
circle whose area shall be equal to one hundred square 
inches, by the well known rule, viz. d= J ae 
where d represents the diameter, a, the area, and .7854 the 
area of a circle, whose diameter is unity. If any other size 
ould be thougt ient. as for inst 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 hundre 
ee will 
square inches, the same re subsist between the f- 
