V. On cerebral anœmia and the effects which follow ligation of the cerebral arteries

The opinions of early writers, which are on this subject both curious and interesting, are stated by Morgagni, and criticised, or rather ridiculed, in Bell’s ‘Anatomy.’ An analysis of the literature up to 1845 is given by Norman Chevers, and up to 1860 by Ehrmann. Exact and important experiments date from those performed by Mayer in 1833. The experimental results obtained are, in abstract, as follows: 1. Mayer:ǁ Horse.-Both carotids ligatured. Results.—Restlessness, gaping, drooping of the eyelids, increased restlessness, staggering. In 21/2 hours eyes and ears insensitive to touch, respiration less frequent, swooning, convulsions. In 2 hours 50 minutes spasm of respiration, tetanic con­vulsions, failure of respiration, death. In the horse the vertebral arteries, at their entrance into the skull, are comparatively of insignificant size.