Capillary Action of Fissures. 193 
produced by the action of fire upon the natural carbonate. 
The happy consequence which he has drawn from his nu- 
merous experiments, that Roman cement may be made in 
almost every place where limestone is found, appears to me — 
beyond all doubt.—Jdem. ; a 
# P 
27. Electricity.—It has been announced to the French 
Academy that M. Becquerel has demonstrated that there is a 
sensible developement of electricity during the ascent of li- 
quids in capillary tubes—Jdem, November 1823. 
28. Capillary action of fissures-—M. Dobereiner, having 
filled several air jars with hydrogen and placed them . 
over water, found that in one of them the water had risen so 
as to fill one third of its volume. No other reason could be. 
assigned than an extremely small crack in the side of the 
vessel. Upon further trial he found that hydrogen would es- 
cape from vessels with extremely small fissures, and that if 
the same vessels were covered with a bell glass or filled with, 
atmospheric air, oxygen, or azote, no change could be ob- 
served in the volume of the gas. This he considers as a 
proof that the atoms of hydrogen are smaller thau those of 
other gases, though surrounded with a larger atmosphere of 
heat. He considers it desirable that some one should treat 
bonic acid, &c. ee 
Another experiment was favourable to this hypothesis. 
Wishing to fill the bulb of a thermometer, through a capilla-_ 
ry opening in the stem, by heating the ball, and plunging the 
fine point in the liquid, he found the alcoho! did not enter 
as the ball cooled. On heating the ball again, fresh bubbles 
of airwere disengaged, but the liquid refused again to enter 
on cooling. On taking the stem out of the alcohol, the air 
rushed in with a hissing sound. He ascribes the effect to 
the fineness of the epening—too small for the atoms of alco- 
hol, but large enough for those of the air which it contains. 
An explanation is thus offered of a fact discovered by Mr. 
Faraday, viz. that alcohol becomes concentrated by leav- 
Vou. [X.——No. 1. 25 
