48o ESSAYS AND OBSERVATIONS 



Art. XX. 



An Account of fome 'Experiments made iritb 

 Opium on Living and Dying Animals ; 

 by Robert Whytt M.D. F, R. S, 

 Fellow of the Royal College of Fhyficians, 

 and Profejfor of Medicine in the Univefffy 

 of Edinburgh *. 



THE ancient phyficians Imagined that 

 opium extinguiflied the flame of life in 

 animals by its exceffive cold j and in later 

 times, there have not been wanting thofe 

 who deduced its efFedls from a quite oppofite 

 quality, whereby it was thought to rarefy the 

 blood and to comprefs the brain or origin 

 of the nerves. Thefe falfe notions, however, 

 of the nature and acftion of opium^ have been 

 refuted by feveral of the moderns, whofe 

 writings have thrown confiderable light 

 upon this fubjedt. 



The following experiments were made 

 with a view ftill further to illuftrate the man- 

 ner in which this wonderful drug produces 



its 



• Auguft 7. 1755. 



