JAN.— MAR. 1857.] for the Frovmces of Madras. S05 
is a full that hardly ever occurs even in a heavy monsoon in 24 
hours, and the Ilain Gauge is, of course, measured every 12 hours. 
Tlie bottle is cleaner, more easily poured from than the vessels 
now in use, and always obtainable. 
The small measuring cylinder was fixed at one fluid ounce, in 
order that it might be easily tested at any Hospital or Dispensary. 
A diameter of I inch, and depth of 2-2 inches is very suitable. It 
is very easy to discern its contents to tenths^ and each tenth de- 
notes the -j-^o of an inch of rain. 
Three or four of these Gauges were tried last Monsoon at the 
Madras Observatory, and gave results exceedingly near the standard 
Pluviometer. 
I first saw a Rain Guage of this kind at the house of a Native 
Gentleman of scientific acquirements at Vizagapatam, but it was 
not quite correct as to dimensions. 
Its cheapness, simplicity, and accuracy, should, I think recom- 
mend it for general use. 
[Report upon Mr. Bayley's proposed new Rain Gauge, by Colonel Smith 
Mint Master, Madras Engineers ] 
The memorandum omits to mention one circumstance which is 
necessary to a clear comprehension of Mr. Bayley's proposal, and 
that is, that the Imperial fluid ounce consists of 1*733, or more ex- 
actly 1-7329625 cubic inches, consequently the fluid ounce measure 
necessarily represents the tenth part of the bulk of rain falling at 
the rate of one inch, in any given period, on an area of 17'33 
square inches. 
With this explanation I trust it will be evident that Mr. Bayley's 
proposed arrangement is as correct as it is scientific, and that its 
precise accuracy merely depends upon the truth of the workman- 
ship and the care of the observer ; which with moderate pains are 
not likely to cause error to a degree likely to interfere with objects 
aimed at by the use of these instruments. 
In order to any practical trial, it would be necessary that five or 
six carefully made Gauges of the new pattern should be exposed 
during rainy weather, in company with a correct standard, and a 
