368 Prof. Faraday on Electric Conduction. 
late in the summer. Although the lakes have no outlet, and 
they are daily receiving this immense supply of water, their level 
is not raised, but on the contrary the borders give evidence that 
they are gradually drying up. We must conclude from these 
facts that the evaporation from the lakes is equal to, if not greater 
than the supply. : 
If we regard the experimental result as a fair measure of the 
evaporation from the lakes, we may readily calculate the amount 
of water taken from them during a mouth or year. e have 
36 cubic inches of water for the daily evaporation from one 
amount of evaporation in, depth, and assume that the quantity 
evaporated is equal during each month in the year, we have as 
before observed, seven feet seven inches and one quarter for the 
yearly evaporation. The conditions which I have detailed, do 
not, however, exist throughout the year. In the rainy months, 
the evaporation is much reduced or perhaps it almost ceases. It 
is almost certain however that the experiment does vot show the 
full amount of evaporation for the summer}; it is undoubtedly 
much greater, and the results can only be regarded as approxi- 
mate. ‘They are however important, and derive greater interest 
from the fact that few experiments of the kind have been made, 
and because the climatic conditions of that region are so peculiar. 
Arr. XXXIX.—On Electric Conduction ; by Professor 
Farapay, D.C.L., F.R.S.* 
Since the time when the law of definite electrdlytic action 
es- 
the electrolytic; the transference of the electric force appearing 
to be essentially associated with the chemical changes which 
occur; the second kind may be called conduction proper ; and 
there the act of conduction leaves the body ultimately as it found 
it. Electrolytic conduction is closely associated with the Jiqui 
state, and with the compound nature and chemical proportions of 
* Proc. Roy. Inst. of Great Britain, Part V, p. 123. 
