re-expanded, and were evidently killed. Four leaves were next immersed
in one part to 875 of water; the action was now slower, but after 22
hrs. all four leaves were closely inflected, and were affected in other
respects as above described. These leaves did not re-expand, though
left for four days in water. This acid acts far more powerfully than
hydrochloric, and is poisonous.
Iodic Acid. One to 437 of water; three leaves were immersed, [page 191]
each in thirty minims; after 3 hrs. strong inflection; after 4 hrs.
glands dark brown; after 8 hrs. 30 m. close inflection, and the leaves
had become flaccid; surrounding fluid not coloured pink. These leaves
were then placed in water, and next day were evidently dead.
Sulphuric Acid. One to 437 of water; four leaves were immersed, each in
thirty minims; after 4 hrs. great inflection; after 6 hrs. surrounding
fluid just tinged pink; they were then placed in water, and after 46
hrs. two of them were still closely inflected, two beginning to
re-expand; many of the glands colourless. This acid is not so poisonous
as hydriodic or iodic acids.
Phosphoric Acid. One to 437 of water; three leaves were immersed
together in ninety minims; after 5 hrs. 30 m. some inflection, and some
glands colourless; after 8 hrs. all the tentacles closely inflected,
and many glands colourless; surrounding fluid pink. Left in water for
two days and a half, remained in the same state and appeared dead.
Boracic Acid. One to 437 of water; four leaves were immersed together
in 120 minims; after 6 hrs. very slight inflection; after 8 hrs. 15 m.
two were considerably inflected, the other two slightly. After 24 hrs.
one leaf was rather closely inflected, the second less closely, the
third and fourth moderately. The leaves were washed and put into water;
after 24 hrs. they were almost fully re-expanded and looked healthy.
This acid agrees closely with hydrochloric acid of the same strength in
its power of causing inflection, and in not being poisonous.
Formic Acid. Four leaves were immersed together in 120 minims of one
part to 437 of water; after 40 m. slight, and after 6 hrs. 30 m. very
moderate inflection; after 22 hrs. only a little more inflection than
often occurs in water. Two of the leaves were then washed and placed in
a solution (1 gr. to 20 oz.) of phosphate of ammonia; after 24 hrs.
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