In 1 hr. 33 m. there was slight inflection; and after 5 hrs. 30 m. the tentacles of all six leaves were considerably, but not closely, inflected. After 23 hrs. 15 m. all had completely re-expanded, and did not appear in the least injured.
Three leaves were immersed, each in thirty minims of a solution of one part to 875 of water, so that each received 1/32 of a grain, or 2.02 mg. After 1 hr. there was much inflection; after 8 hrs. 30 m. all the tentacles and the blades of all three were closely inflected. Four other leaves were also immersed in the solution, each receiving the same amount of salt as before, viz. 1/32 of a grain. They all soon became inflected; after 48 hrs. they began to re-expand, and appeared quite uninjured, though the solution was sufficiently strong to taste saline.
Sodium, Iodide of.--Half-minims of a solution of one part to 437 of water were placed on the discs of six leaves. After 24 hrs. four of them had their blades and many tentacles inflected. The other two had only their submarginal tentacles inflected; the outer ones in most of the leaves being but little affected. After 46 hrs. the leaves had nearly re-expanded. Three leaves were also immersed, each in thirty minims of a solution of one part to 875 of water. After 6 hrs. 30 m. almost all the tentacles, and the blade of one leaf, were closely inflected.
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 this produced no apparent effect. They were then put into a solution of one part of carbonate of ammonia to 218 of water; the glands were immediately blackened, and after 1 hr.