of American Geologists and Naturalists. 115 
CO,, are maintained at a common and permanent temperature 
during the process by immersion in a large volume of water. 
_ This operation even with the most sluggish absorbents is com- 
pleted in a short time and thereby various sources of error are 
avoided. 
The absorption of CO, by pure water was determined at suc- 
cessive temperatures from 32° to 100°, and a curve constructed 
representing the law of absorption as dependent on temperature. 
This the authors regard as the first systematic investigation of 
the influence of temperature upon absorption, yet made 
In the case of other liquids, the experiments were for the 
r. 
The following is a list of the substances which had thus far 
which the gas, whose carbonic acid is to be measured, is desiccated 
phere, of the air of mines, hospitals, é&c., as employed. by Bous- 
singault and Lewy, LeBlanc, Orfila and others, in all of which 
1e air was passed slowly over a large surface of sulphuric acid. 
a8 a prliminary step to the analysis. 
_ 13. On the Transporting Power of Currents ; by Prof. W. B. 
Rocers.—Prof, W. B. Rogers remarked it polar be 
Tegretted, that we were yet in possession of no certain data on 
the subject of the transporting power of currents. The usual state- 
ments affirming that at a certain rate of motion, a stream will car- 
