From A. H. Garrod to Francis Darwin 30 June 1
11, Harley Street, | Cavendish Square, W.
I made an attempt this morning to take a sphygmograph tracing during fright, & fear that I have not been very successful. At the Hospital the house-physician & I went to a woman, Abt 30, & commenced putting on the sphygmograph,2 & when quite ready asked her if she minded being hurt a little, upon which she, being rather of a nervous temperament, jumped up & said she would have nothing done to her at all & wanted to dress & leave immediately. She was very much terrified & it was with great difficulty that we could get her quiet enough to take a trace & we only did so by telling her I did not mean to hurt her at all. At last, she still being very excited & frightened, we took the lower trace & after about 10 minutes the two upper ones. She did not quiet down for some time afterwards & then remained suspiciously nervous, so that it was not possible to take a normal trace. The pulse did not become much increased in rapidity after the fright, being nearly 100 a minute before the fright & but little more during it. On the whole I think that little or nothing can be learnt from the trace.
I have been looking up any points that seem to bear on the point your father is working at & think that the following two may be of use.3
I. In P. Lorain’s work on the pulse there are some normal sphygmograms of a woman (p. 193. p. 194) & on p. 194 is one of the same woman in a rage. It is very different to the others & much quicker.4
II. In a paper by L. Lortet of Lyons in the Annales des Sciences Nat. Sci. 5. Tom VII. p296 & seq. the wonderful increase in the rapidity of the blood current on a horse scenting food & commencing to eat is shown diagrammatically in a most excellent manner, & this increase in blood current may assist in the increased glandular action necessary for the digestion of the food. There are other kindred points of interest in the same paper.5
I shall be very happy to lend you Lorain’s book if it is of any service to you.
Upon my theory of pulse rate, the only way that fright &c can influence the circulation for good is by its influence on the pneumogastric nerve, which thus indirectly alters the calibre of the coronary small arteries & so modifies the nutrition of the heart.6
I have not yet had any ruminant dead, so have not yet got any lig. nuchae for you, but I have not forgotten it.7
Hoping to see you when you have any spare time | Believe me | Yours very truly | A. H. Garrod
Sends an account of an attempt to take a sphygmograph tracing of a woman during fright
and some references that might apply to CD’s work on pulse rates during rage and fright.
Please cite as
Darwin Correspondence Project, “Letter no. 8399,” accessed on 25 April 2017, http://www.darwinproject.ac.uk/DCP-LETT-8399