VOL. XXIX.] PHILOSOPHICAL TKANSACTlOxVS. Ql 



ports have been sometimes spread among the vulgar, yet having gone on pur- 

 pose to the houses whence such rumors have arisen, I have found the whole to 

 be absolutely false. It is now 8 years since I have been an eye-witness of these 

 operations ; and to give a greater proof of the sedulity I have used in this dis- 

 quisition, I shall relate 2 histories. 



In a certain family, a boy of 3 years old, was afflicted with the falling-sick- 

 ness, the king's-evil, an hereditary pox, and a long marasmus. The parents 

 were desirous to have the incision made upon him ; the small-pox were thrown 

 off with ease ; about the 40th day he died of his marasmus. In another family, 

 a girl of 3 years old, was troubled with the like fits, strumous, attended with an 

 hereditary lues, and labouring under a colliquative looseness for 3 months. The 

 operation was performed on this child; she came off very well of the small -pox, 

 which was all over the 1 5th day ; on the 32d she died of her looseness, which 

 had never left her the whole time. But it is true, I never maintained the ino- 

 culation as a panacea, or cure for all diseases ; nor do I think it proper to be 

 attempted on persons like to die. 



Then follows a long aetiologia respecting the manner in which this author 

 supposes the variolous contagion to act upon the human body. He supposes 

 it to act upon the mass of blood after the manner of a ferment or leven, and 

 that all the symptoms which take place in the natural or inoculated small-pox 

 are to be accounted for in the 1st instance, from the commotion excited in 

 the blood, (and thence upon the constitution at large); in the next place 

 from the defecation or separation of the vitiated particles from the healthy, 

 &c. &c. Respecting a theory now universally exploded, it cannot be necessary 

 to enter into further particulars. 



Tfieoremata qucedam infinitam Materice Divisibilitaiem spectantia, qiue ejusdem 

 raritatem et tenuem compositionem demonstrant^ quorum ope plurimce in Pliysica 

 tolluntur difficultates. A Johanne Keill, M. D. S. R, S. N° 339, P* 82. 



These theorems on the divisibility of matter, and the tenuity of its com- 

 position, were afterwards printed in the author's introduction to Natural Philo 

 sophy, or Philosophical Lectures, where the subject is given more fully, and 

 where it forms part of the 5th Lecture. See p. of the Latin edition, or 

 p. 63 of the English one. 



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