Aluminium, Nitrate of. Four leaves were immersed in 120 minims of a
solution of one part to 437 of water; after 7 hrs. 45 m. there was only
a trace of inflection; after 24 hrs. one leaf was moderately inflected.
The evidence is here again doubtful, as in the case of the chloride of
aluminium. The leaves were then transferred to the same solution, as
before, of phosphate of ammonia; this produced hardly any effect in 7
hrs. 30 m.; but after 25 hrs. one leaf was pretty closely inflected,
the three others very slightly, perhaps not more so than from water.
Aluminium and Potassium, Sulphate of (common alum). Half-minims of a
solution of the usual strength were placed on the discs of nine leaves,
but produced no effect.
Gold, Chloride of. Seven leaves were immersed in so much of a solution
of one part to 437 of water that each received 30 minims, containing
1/16 of a grain, or 4.048 mg., of the chloride. There was some
inflection in 8 m., which became extreme in 45 m. In 3 hrs. the
surrounding fluid was coloured purple, and the glands were blackened.
After 6 hrs. the leaves were transferred to water; next morning they
were found discoloured and evidently killed. The secretion decomposes
the chloride very readily; the glands themselves becoming coated with
the thinnest layer of metallic gold, and particles float about on the
surface of the surrounding fluid.
Lead, Chloride of. Three leaves were immersed in ninety minims of a
solution of one part to 437 of water. After 23 hrs. there was not a
trace of inflection; the glands were not blackened, and the leaves did
not appear injured. They were then trans- [page 185] ferred to the
solution (1 gr. to 20 oz.) of phosphate of ammonia, and after 24 hrs.
two of them were somewhat, the third very little, inflected; and they
thus remained for another 24 hrs.
Tin, Chloride of. Four leaves were immersed in 120 minims of a solution
of about one part (all not being dissolved) to 437 of water. After 4
hrs. no effect; after 6 hrs. 30 m. all four leaves had their
submarginal tentacles inflected; after 22 hrs. every single tentacle
and the blades were closely inflected. The surrounding fluid was now
coloured pink. The leaves were washed and transferred to water, but
next morning were evidently dead. This chloride is a deadly poison, but
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