298 ESSAYS AND OBSERVATION S 



pendent of the circulation of the blood, 

 (as Drs Jones, Alfton, Van Swieten, and 

 Kaau Boerhaave * had endeavoured tq 



prove) 



* Dr John Jones, by telling us in fome places, that 

 the urine and fweat fmell of opium, after taking that 

 drug in confiderable quantity, allows, that it enters thes 

 blood ; yet, from the foiall proportion it niuft bear to 

 the whole mafs, denies, that, in that way, it can re- 

 markably affe(!t the ceconomy ; and fays, " It is paft all 

 •« doubt, that opium produces its common efifeds, while 

 *' it is in the ftorrach, and before it arrives at the blood, 

 •• and therefore does not operate as an alterative there- 

 *♦ of." See Jones's Myfteries of Opium revealed. Chap. 

 12 .p. 93- and 94, 



Alfton in Med. EfT. vol. j. art. 12. § 12. N. i. and[ 

 2. p. 140, 4. Edinburgh. " I infer, therefore, imo, 

 «* That the anodyne and hypnotic virtues of opium do 

 " not depend on its aftlon on the brain, or on the bloocl, 

 •• whether externally or internally ufed, 



*• 2do, That it afFefls firft and principally the nerves 

 «« to which it is applied ; next, fuch as are more imme- 

 «« diately conneded or communicate with them ; then 

 " thofe which fervefor fenfation and voluntary motion; 

 *' and, laft of all, byccnfent, the whole nervous fyftem.V 



Van Swieten C. in B. § 229. n 2. 



•• Unde (opiuoa) non videtur agere, quia folutiim et 

 «« humoribus m'ftum circulationis lege ad cerebrum de- 

 *' fe; tur, (ed quia interiori venthculi fupcrliciei appli- 

 *• catum manet." 



Abrah. 



