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Darwin Correspondence Project

From John Rae1   21 February 1855

13 Salisbury Street | Strand

21st. Feby 1855

My Dear Sir

I believe the ice driven down the Mc Kenzie may be driven some hundred miles from that rivers mouth before it becomes wasted— The pressure of the water is so great that the ice is broken up when in some places (as along the banks where overflowings take place) fully six or 8 feet thick— Ice of this thickness would take a long while to dissolve, more particularly when a number of pieces are heaped one upon another as is often the case—

That seeds of plants should be thus conveyed long distances is extremely probable although I have no data by which to prove it—

What appears to me the most likely way in which the seeds of Arctic plants are so widely disseminated is by the winter gales of Northerly and North West winds— These sweep the ground and in many places denude it of snow and at the same time displace seeds and even portions of plants themselves— This may occur any time in winter, and the seeds so driven may get another “lift ” in the spring in the same way and may also be moved a long way farther, in the way you suggest— I have in hundreds of places seen ice forced sufficiently high on the land to afford an opportunity for the plants to vegetate when the ice thawed—

Now I have no proof of the above but having lived much on the banks of one or two of the large streams falling into Hudsons Bay, and also on the Mc Kenzie, and seeing large masses of ice drive down those streams for days and perhaps weeks after the main body of ice had disappeared far to seaward, I think it not unreasonable to suppose that some of these masses might go a long way before being broken up or melted—

I am far from thinking your question a simple one, on the contrary it would require long and close investigation to decide it with certainty—

Some unexpected bad news from the north obliges me to leave town tomorrow, but I contemplate being here again in a fortnight so that any other questions you may ask I shall be always most happy to reply to in the best manner I can—

Believe me | My Dear Sir | very truly yours | John Rae Charles Darwin Esqre. | &c &c &c

CD annotations

1.1 some hundred miles] underl brown crayon
1.4 overflowings … thick] scored brown crayon
1.4 six or 8 feet thick] underl brown crayon
scored brown crayon
2.1 extremely probable 2.2] underl brown crayon
scored brown crayon
double scored brown crayon
double scored brown crayon
Top of first page: ‘18’2 brown crayon, circled brown crayon; ‘Ice & Seeds’ brown crayon


Rae had been a surgeon with the Hudson’s Bay Company. During the years 1847 to 1854, he was involved in several of the expeditions in search of Sir John Franklin, during the last of which he obtained conclusive proof of Franklin’s death. After his return to England in October 1854, he was a celebrated expert on the Arctic.
CD’s portfolio 18 contained notes on geographical distribution. CD referred to Rae’s information in Natural selection, p. 562.


Natural selection: Charles Darwin’s Natural selection: being the second part of his big species book written from 1856 to 1858. Edited by R. C. Stauffer. Cambridge: Cambridge University Press. 1975.


Comments on possibility of transport of seeds of Arctic plants by ice.

Letter details

Letter no.
John Rae
Charles Robert Darwin
Sent from
London, Salisbury St, 13
Source of text
DAR 205.2: 249
Physical description
4pp †

Please cite as

Darwin Correspondence Project, “Letter no. 1636,” accessed on 27 February 2021,

Also published in The Correspondence of Charles Darwin, vol. 5