skip to content

Darwin Correspondence Project

From G. B. Thornbery   27 March 1873

3 W〈ellin〉gton Road | 〈St〉 Mary’s | Peckham | SE

27th March 1873.

Charles Darwin Esq


I can only plead having read several of your books as an excuse for addressing you personally— Altho〈ugh〉 not by any means a naturalist I have been very much interested in several of your works and it is since reading your remarks on—“movements which are no longer useful but still inherited”—that I have been puzzled about the movement of the arms of man during the act of walking—1 It has struck me that this may possibly be a vestige of the movement of the four limbs of the lower animals for locomotive purposes— As I said before I am no anatomist and there may therefore be some simple explanation of this movement but I have noticed the swinging of the arms in very young children who could not have had time to acquire the habit—and from my own sensations I do not believe it in any way assists progression— Soldiers march none the less steadily on account of their arms being kept close to the sides and girls when well trained soon overcome the tendency to swing the arms and hereafter certainly appear to walk q〈uite〉 as easily and gracefully without 〈s〉o doing— After repeated attemp〈ts〉 I have found it quite impossible to bring the right arm and leg forward togethe〈r〉 & v.v. for any number of steps in succession— This might be used as 〈an〉 argument to show that the moveme〈nt must〉 be of some use to man but all the lower animals move the two pairs of limbs alternately and not in accordance & therefore if an inherited movement it would take that form. If you can give me any explanation of this movement or direct me where to look for such explanation you 〈w〉ill greatly oblige

Yours very truly | Gregory B. Thornbery


In the first chapter of Expression, CD described three general principles of expression, the first being the ‘principle of serviceable associated habits’, by which movements continued to be performed even when no longer of use (Expression, p. 28).


Expression: The expression of the emotions in man and animals. By Charles Darwin. London: John Murray. 1872.


Has read several of CD’s books; is curious about his remarks on "movements which are no longer useful but still inherited". Asks CD’s opinion on why people still swing arms with opposite leg in walking.

Letter details

Letter no.
Gregory Beddome Bromberg
Charles Robert Darwin
Sent from
Source of text
DAR 160: 316
Physical description

Please cite as

Darwin Correspondence Project, “Letter no. 8827,” accessed on 20 September 2021,

Also published in The Correspondence of Charles Darwin, vol. 21