My dear Hooker

I got your letter of the 1^st. this morning;² & a real good man you have been to write. Of all the things I ever heard, M^rs. Hooker’s pedestrian feats beats them. My Brother is quite right in his comparison of “as strong as a woman”,—as a type of strength.— Your letter, after what you have seen in Himalaya &c, gives me a wonderful idea of the beauty of the Alps. How I wish I was one half or one quarter as strong as M^rs. Hooker: but that is a vain hope. You must have had some very interesting work with glaciers &c.³ When will the glacier structure & motion ever be settled! When reading Tyndall’s paper it seemed to me that movement in the particles must come into play in his own doctrine of pressure;⁴ for he expressly states that if there be pressure on all side, there is no lamination: I suppose I cannot have understood him, for I sh^d. have inferred from this that there must have been movement parallel to planes of pressure. Sorby read paper to Brit. Assoc. & he comes to conclusion that Gneiss &c may be metamorphosed cleavage or strata; & I think he admits much chemical segregation along the planes of division.⁵ I quite subscribe to this view, & sh^d. have been sorry to have been so utterly wrong, as I sh^d. have been, if foliation was identical with stratification.⁶

I have been no where & seen no one & really have no news of any kind to tell you.— I have been working away as usual (floating plants in salt-water inter alia & confound them, they all sink pretty soon, but at very different rates) working hard at Pigeons &c &c By the way I have been astonished at differences in skeletons of domestic Rabbits:⁷ I showed some of the points to Waterhouse & asked him whether he could pretend that they were not as great as between species, & he answered “they are a great deal more”.—⁸ How very odd it is that no zoologist sh^d. ever have thought it worth while to look to the real structure of varieties.—

I most earnestly hope that at Vienna you will make particular enquiries about the pure Laburnum, which one year bore the hybrid flowers & on one sprig the C. purpureus.—⁹ D^r. Reissik(?) is name of man I think.— Bentham¹⁰ will not believe that it was a pure Laburnum, & it does seem quite incredible, notwithstanding the clear statements in the Flora.¹¹ Please enquire particularly whether the hybrid or purple or pure bears seeds: I have just got the seeds of a yellow branch from the sterile hybrid to sow & see what will come up.— Really this case ought to be investigated,¹² & if you, the King of Sceptics believe, all others may.—

My poor wife keeps very uncomfortable, but rather better than she was.¹³

With our kindest regards to M^rs Hooker. | Believe me | My dear Hooker | Ever yours | C. Darwin