Chap. VIIL EFFECTS OF VARIOUS SALTS. 183 



Magnesium, Sulphate of. — Half-minims of a solution of one part 

 to 218 of water were placed on the discs of ten leaves, and pro- 

 duced no effect. 



Barium, Acetate of. — Four leaves were immersed in 120^minims 

 of a solution of one part to 437 of water, and after 22 hrs. there 

 was no inflection, but the glands were blackened. The leaves 

 were then placed in a solution (1 gr. to 20 oz.) of phosphate of 

 ammonia, which caused after 26 hi's. only a little inflection in 

 two of the leaves. 



Barium, Nitrate of. — Four leaves were immersed in 120 minims 

 of a solution of one part to 437 of water ; and after 22 hrs. there 

 was no more than that slight degree of inflection, which often 

 follows from an immersion of this length in pure water. I 

 then added some of the same solution of phosjDhate of ammonia, 

 and after 30 m. one leaf was greatly inflected, two others 

 moderately, and the fourth not at all. The leaves remained 

 in this state for 24 hrs. 



Strontium, Acetate of. — Four leaves, immersed in 120 minims of 

 a solution of one part' to 437 of water, were not affected in 

 22 hrs. They were then placed in some of the same solution 

 of phosphate of ammonia, and in 25 m. two of them were 

 greatly inflected ; after 8 hrs. the third leaf was considerably 

 inflected, and the fourth exhibited a trace of inflection. They • 

 were in the same state next morning. 



Strontium, Nitrate of. — Five leaves were immersed in 120 

 minims of a solution of one part to 437 of water ; after 22 hrs. 

 there was some slight inflection, but not more than sometimes 

 occurs with leaves in water. They were then placed in the 

 same solution of phosphate of ammonia ; after 8 hrs. three of 

 them were moderately inflected, as were all five after 24 hrs. ; 

 but not one was closely inflected. It appears that the nitrate of 

 strontium renders the leaves half torpid. 



Cadmium, Chloride of. — Three leaves were immersed in ninety 

 minims of a solution of one part to 437 of water ; after 5 hrs. 

 20 m. slight inflection occurred, which increased during the 

 next three hours. After 24 hrs. all three leaves had their 

 tentacles well inflected, and remained so for an additional 24 

 hrs.; glands not discoloured. 



Mercury', Perchloride of. — Three leaves were immersed in ninety 

 minims of a solution of one part to 437 of water ; after 22 m. 

 there was some slight inflection, which in 48 m. became well 

 pronounced; the glands were now blackened. After 5 hrs. 

 35 m. all the tentacles closely inflected; after 24 hrs. still 



