My dear Sir

I owe so much to Birmingham for the very great honours which it has conferred on me, chiefly, as I believe, through you, that I greatly desire to do what you request. But in truth I cannot   During my whole life I have never tried to write, excepting when my mind is full of some subject, & then I can only give the facts & draw inferences—¹ I am old & cannot change my habits & I have been accustomed to work for many months or years on a subject before writing on it. I always admire & sometimes envy men, like Huxley,² whose minds seem crammed with new ideas, which they can pour out on the shortest notice. But I am not one of those fortunate individuals.

Less than a week ago I was asked by a man, whom I wished to oblige, to do something analogous, & was forced to refuse.³ I can assure you that it causes me much regret not to do what you ask, but I feel it impossible. I could almost as easily get up & harangue a public meeting on some subject

My dear Sir | Yours sincerely | Ch. Darwin