912 
cal discussion accompanied the description of 
the experiments. 
‘The Solubility of Calcium Carbonate in 
Aqueous Solutions of certain Electrolytes and 
in Equilibrium with Air,’ by Frank K. Cameron 
and Atherton Seidell : 
Since the solubility of the calcium carbonate 
is dependent upon the amount of carbon di- 
oxide in the gas phase in contact with the solu- 
tion, the solutions were brought to equilibrium 
with air, previously washed in dilute sulphuric 
acid, and bubbled through the solutions by 
means of an aspirator. It was found that the 
curye for sodium chloride presented a well- 
marked maximum point. No normal carbon- 
ates were in the solution, the calcium dis- 
solving entirely as the hydrogen carbon. 
In sodium sulphate solutions, the major part 
of the calcium dissolved as the hydrogen car- 
bonate, though at the higher concentrations 
normal carbonates were also found. The curve 
for this pair of electrolytes showed no maximum 
point. Curiously, it was found that calcium 
carbonate was much more soluble in solutions 
of sodium sulphate than in solutions of sodium 
chloride, at all concentrations. 
The presence of solid gypsum was found to 
producé an effect on the solubility of calcium 
carbonate in sodium chloride solutions, greater 
in amount but similar in nature to that pro- 
duced by calcium carbonate on the solubility of 
the gypsum in sodium chloride solutions, and 
described in the preceding paper. Practical 
applications of the work were pointed out and 
a theoretical discussion of the results obtained 
was given. 
L. S. Munson, 
Secretary. 
TORREY BOTANICAL CLUB. 
Ar the meeting of the Club on March 27, 
1901, the first paper of the evening was by Dr. 
John K. Small on ‘The North American Gen- 
era of Mimosaceze.’ Dr. Small exhibited a 
uniform series of diagrammatic drawings, illus- 
trating the flowers and fruit of each of these 
genera, and explained his proposed classifica- 
tion, replacing the previous artificial grouping. 
The variability of the fruit in valves, margins 
and cross-partitions was commented on. Dis- 
SCIENCE. 
[N. S. Vox. XIII. No. 336. 
cussion of the common sensitive plant followed, 
in which it was remarked that the sensitive- 
ness to shock is so delicate as to be stimulated 
by holding a burning-glass near, or by drops of 
rain-water on first falling, or by holding a 
sponge of ammonia or of chloroform near. The 
utility seems unknown, except as the hot sun 
setting the leaves on edge prevents injury from 
intense sunlight. Sachs’s suggestion was that 
the depression of the leaves served as a protec- 
tion from hail; but it now appears that the 
native center of the plant is chiefly in the Ori- 
noco regions where hailstorms are unknown. 
Much energy is exhausted by folding, and it is 
well known that the greenhouse sensitive- 
plants are frequently worked to death by re- 
peated irritation. 
The second paper, by Dr. Rydberg, soon to 
be printed, was on ‘The Oaks of the Rocky 
Mountains,’ in which region eleven species 
were described in Sargent’s ‘Silva,’ a number 
now increased by Dr. Rydberg to twenty-eight. 
E. 8S. BURGESS, 
Secretary. 
THE ONONDAGA ACADEMY OF SCIENCE. 
THE 47th regular meeting was held in the 
Historical rooms, Friday P. M., May 17, 1901. 
The first paper was by Dr. John Van Duyn, 
entitled, ‘The Terrestrial Life of Porto Rico.’ 
Dr. Van Duyn spoke entertainly concerning 
many facts and observations made during his 
recent visit, as the deep blue of the ocean, the 
appearance of different constellations, the char- 
acter of the rocks and their probable formation, 
the differences in wind and climate of the north- 
ern and southern shores of the island, the ani- 
mal and plant forms, and the inhabitants. The 
latter are a mixture of Spaniard, negro and 
native Indian. Although it has been maintained 
by high authority that the Indian types have 
been entirely lost, Dr. Yan Duyn was positive 
that this was not so. He believes that the race 
possesses vast capabilities for development. 
Asecond paper, entitled ‘The Marine Life of 
Porto Rico,’ was given by Dr. C. W. Hargitt, 
of Syracuse University. He briefly narrated 
the early work in the natural history of Porto 
Rico and then told of the recent expedition of 
the Fish Hawk to those waters, and of the 
