cases the hypothalamus in autopsy material. Over thirty normal rabbits, submitted to 

 multiple episodes of sub- lethal hyperthermia and then autopsied and serial sections 

 cut of every brain showed no such lesions. Focal areas in the brains of men killed 

 by hyperthermia have been found by American observers; but the American material 

 was always haemorrhagic, in contrast to our findings which indicated ischaemia. 

 The Americans gave narcotic to their human cases before exposure to great heat. 

 Clinical signs of cerebellar damage have been reported by British observers in human 

 cases as a sequela of hyperthermia (heat stroke) and some American observers have 

 demonstrated destruction of the nerve cells in the hyperthermic nuclei in such cases. 

 There is a tendency for those patients not killed at once by their brain injuries, to 

 recover with suitable cooling therapy and supportive treatment for the circulatory 

 depression. 



Nervous sequelae may occur in these recovered persons, and sometimes the 

 nervous changes clear up with a passage of time in a temperate climate: not all do, 

 however. There is not time to describe any further experiments; even if the patience 

 and enthusiasm of this exemplary audience could bear any more of this rather tech- 

 nical and unexciting chronicle. We have to thank Sir David Brunt for rescuing the 

 subject of heat effects from oblivion, and for rescuing it from obscurity by clothing 

 its scientific nakedness in mathematical expressions, which, though hardly the glass 

 of fashion or the mould of form, none the less are graceful and elegant interpreta- 

 tions. I have also to thank Dr J, L. Cloudsley- Thompson for the opportunity to give 

 expression to my views. 



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