My dear Sir

I am very much obliged to you for having sent me a copy of the Bill on Vivisection as introduced by you.—² By undertaking this work, you have in my opinion done a great service in the cause of humanity & Science. I have had no recent communication with any physiologist, but I fear that the clause about registering every experiment, done without anæsthetics, though in itself a good step, may be a source of much trouble & difficulty, especially from the impossibility of explaining to the unscientific the probable advantage of any particular experiments.³

Pray believe me, my dear Sir | yours faithfully and obliged | Charles Darwin