LEV I SON, NEWARK IGNEOUS ROCKS 
125 
volcanic districts it thus absorbs sulphurous acid and hydric sulphide; over 
bog lands, marsh gas; and in manufacturing districts, hydric chloride and 
chlorine. 1 Rain and dew spreading over growing land vegetation would seem 
likely to acquire considerable of the oxygen exhaled as a function of growth. 
The seepage and overflow of pools and streamlets in which algse are flourish¬ 
ing would be highly charged with oxygen. I have collected in a few days 
about half a liter of oxygen, pure enough to relight a glowing taper, by 
simply inverting a jar over a rank growth of filamentous algae in a self-sus¬ 
taining aquarium. Any meteoric water seeping through decaying vegetation 
would seem likely to absorb considerable carbonic acid and perhaps crenic 2 
or other organic acids and compounds, and such water previously oxygen¬ 
ated would seem likely to acquire a greater charge of carbonic acid by its 
own reaction upon such material. 3 Oxygenated water reaching the trap 
more directly would evidently have a reaction upon it differing from the 
above. 
“By the continuous action of water charged with carbonic acid, even in 
small proportion, granite and other hard rocks are disintegrated, and the 
changes effected, insignificant as at first sight they may appear, in the lapse 
of time become of great extent and importance.” 4 
To determine whether the New Jersey trap rock is more soluble in water 
charged with carbonic acid than in pure water, the experiment previously 
described was repeated, with the modification that for about an hour each 
morning and evening of the sixteen days, carbonic anhydride, freed from 
every trace of hydrochloric acid vapor, was allowed to bubble slowly through 
the water in which the trap was immersed. The total amount of gas gen¬ 
erated by about 15 cc. of commercial hydrochloric acid acting on an excess 
of marble was the quantity usually transmitted. The residue from the 
200 cc. of the solution was white and weighed 0.1226 gramme. Hence one 
liter of water thus partly charged with carbonic acid acting upon 500 grammes 
of trap from Upper Montclair, N. J., for sixteen days would dissolve 0.6130 
gramme of its constituent material. 
The trap solution was much less turbid than that in pure water. The 
material which caused its turbidity collected upon the filter contained some 
particles which appeared to be trap mechanically separated. These were 
removed and weighed 2*4 milligrammes after ignition. The remainder of the 
material weighed 21.4 milligrammes. The latter would correspond to 0.1070 
gramme produced by the action of one liter of water containing C0 2 on 500 
grammes of trap in sixteen days. 
1 V. B. Lewes: op. cit., p. 215. 
2 G. Bischoff: Elem. Chem. & Phys. Geol., Vol. 1, p. 166. London, 1854. 
3 V. B. Lewes: op. cit., p. 100. 
4 W. A. Miller: Elem. Chem., Part 2, p. 50. N. Y„ 1868. 
