My dear Sir

It has been a great pleasure to me to receive your letter. I will at once proceed to make some notes on the Paper you have been so kind as to send to me & particularly on the marked passages.¹

Ad 3. Sodium salts may be injected into the circulation of mammals in very large doses without effect. Very small doses of potassium salts produce death by suddenly arresting the contractions of the heart.² This fact I have verified experimentally.

Ad 7. I can give you no explanation of the result obtained with Extract of Belladonna.³ I will write again on this subject

Ad 8. On the matter of Calabar bean I will write to D^r Fraser⁴

Ad 11 I believe that the citrate of Strychnine w^d. be as good a salt as could be used.⁵

Ad 14 The negative result in the case of Curare is very interesting. It may I think be compared with the equally negative result obtained with Colchicine. Both are muscular poisons. I will send you some veratrine the alkaloid of Cevadilla which acts on muscle in the same way as Colchicine and does not act on nerve    If it is found that veratrine does not act on the Sundew it would I think be of interest.⁶

Another agent (very accessible) which acts on nerve & is without action on muscle is glycerine. If a very weak solution of glycerine in water produces inflection, this w^d. indicate that the excitability of Drosera is allied to that of nerve rather than to that of muscle.⁷

No doubt the most important fact of all is the one recorded in Par. 2. The action cannot be due to the presence of nitrogen—nor to the presence of nitrogenous comp^ds. for these exist in vegetable liquids—in the very tissues and juices of the leaf itself— It must be dependent on the action of a ferment. To determine this it would be interesting to observe 1^st. whether carbolic acid acts on the Drosera in ferment-destroying dose (say in $\frac{1}{2}$ per cent solution) & secondly whether the same agent when added to an animal liquid (e.g. Saliva) inhibits its action.⁸

The best exp^t. for this purpose would be first to give the leaf some carbolic acid (half per cent solution) and then follow it with the Saliva.

If it is not too late and I could do so without disturbing either you or your Droseras I should like extremely to witness some of the facts⁹

Believe me my dear Sir | very truly yours | J S B Sanderson