Dear Mr Darwin

Before leaving England for the Alps I corrected the proofs of a lecture on the Origin of alpine vegetation of which a copy has I trust been forwarded to you, in the hope that you might take the trouble of reading it.¹ I am fully aware that in addition to the inherent difficulties of the undertaking arising from the imperfection of existing materials & my own inadequate knowledge of those that exist—a popular lecture is not a satisfactory form in which to put forward views that require for their exposition a vast array of well-arranged facts to many of which I could give no space whatever in the lecture. But I thought that in this brief and incomplete form I might at least succeed in directing to the subject the attention of some of those best able to judge of it, and that if as I hope I should be able to discuss the whole matter more fully hereafter I could not fail to benefit by the opinions which the present essay might elicit—

It is quite unnecessary to say that there is no one whose judgement I look to with such deep interest as yours—quite certain that it will in no way be affected by the circumstance that on one or two points I have ventured to dissent from opinions that you have sanctioned—² Of all the arguments that seem to me to favour the belief in the high antiquity of the existing genera & tribes of plants one of strongest, as I think, is that derived from the great differences in the distribution of very many natural orders & conspicuous genera. Making every allowance for peculiarities of structure that must in some cases have largely affected the distribution of certain groups, either in a positive or negative direction, it yet seems almost impossible to account for the facts without allowing vast intervals of time & corresponding changes on the earth’s surface between the dates at which different groups were distributed— Of course any attempt to illustrate this argument in detail would have been impossible in my lecture but to those who know the facts I think it will not be without weight.

If you should favour me with a word of remark on the subject it will be forwarded from my London address given above.

I remain always | very truly yours | John Ball