Sodium, Bromide of. Half-minims of a solution of one part to 437 of
water were placed on six leaves. After 7 hrs. there was some
inflection; after 22 hrs. three of the leaves had their blades and most
of their tentacles inflected; the fourth leaf was very slightly, and
the fifth and sixth hardly at all, affected. Three leaves were also
immersed, each in thirty minims of a solution of one part to 875 of
water; after 40 m. there was some inflection; after 4 hrs. the
tentacles of all three leaves and the blades of two were inflected.
These leaves were then placed in water, and after 17 hrs. 30 m. two of
them were almost completely, and the third partially, re-expanded; so
that apparently they were not injured. [page 179]
Potassium, Carbonate of (pure). Half-minims of a solution of one part
to 437 of water were placed on six leaves. No effect was produced in 24
hrs.; but after 48 hrs. some of the leaves had their tentacles, and one
the blade, considerably inflected. This, however, seemed the result of
their being injured; for on the third day after the solution was given,
three of the leaves were dead, and one was very unhealthy; the other
two were recovering, but with several of their tentacles apparently
injured, and these remained permanently inflected. It is evident that
the 1/960 of a grain of this salt acts as a poison. Three leaves were
also immersed, each in thirty minims of a solution of one part to 875
of water, though only for 9 hrs.; and, very differently from what
occurs with the salts of soda, no inflection ensued.
Potassium, Nitrate of. Half-minims of a strong solution, of one part to
109 of water (4 grs. to 1 oz.), were placed on the discs of four
leaves; two were much injured, but no inflection ensued. Eight leaves
were treated in the same manner, with drops of a weaker solution, of
one part to 218 of water. After 50 hrs. there was no inflection, but
two of the leaves seemed injured. Five of these leaves were
subsequently tested with drops of milk and a solution of gelatine on
their discs, and only one became inflected; so that the solution of the
nitrate of the above strength, acting for 50 hrs., apparently had
injured or paralysed the leaves. Six leaves were then treated in the
same manner with a still weaker solution, of one part to 437 of water,
and these, after 48 hrs., were in no way affected, with the exception
of perhaps a single leaf. Three leaves were next immersed for 25 hrs.,
each in thirty minims of a solution of one part to 875 of water, and
160