valuable memoir. We see the effects on the veins of the head,
in their prominence, and in the purple colour of the face
of a man who coughs violently from being half choked.
I may mention, on the same authority, that the whole eye
certainly advances a little during each violent expiration.
This is due to the dilatation of the retro-ocular vessels,
and might have been expected from the intimate connection of
the eye and brain; the brain being known to rise and fall with
each respiration, when a portion of the skull has been removed;
and as may be seen along the unclosed sutures of infants' heads.
This also, I presume, is the reason that the eyes of a strangled
man appear as if they were starting from their sockets.


[14] I am greatly indebted to Mr. Bowman for having introduced
me to Prof. Donders, and for his aid in persuading this great
physiologist to undertake the investigation of the present subject.
I am likewise much indebted to Mr. Bowman for having given me,
with the utmost kindness, information on many points.

[15] This memoir first appeared in the `Nederlandsch Archief voor Genees
en Natuurkiinde,' Deel 5, 1870. It has been translated by Dr. W. D. Moore,
under the title of "On the Action of the Eyelids in determination of Blood
from expiratory effort," in `Archives of Medicine,' edited by Dr. L. S. Beale,
1870, vol. v. p. 20.

With respect to the protection of the eye during violent expiratory
efforts by the pressure of the eyelids, Professor Donders concludes from
his various observations that this action certainly limits or entirely
removes the dilatation of the vessels.[16] At such times, he adds,