460 DISEASES OF SENSATION. SKCT.XXXlTf 2. 



variolous patients, fo as to cover the whole fkin 

 almoft with puflules, does not arife from any che- 

 mical fermentation in the blood, but that it i 

 owing to morbid motions of the fine extremities 

 of the capillaries, or glands, whether thefe be rup- 

 tured or not, appears from the quantity of this 

 matter always cor ref ponding with the quantity of 

 the fever ; that is, with the violent exertions of thofe 

 glands and capillaries, which are the terminations 

 of the arterial fyftem. 



The truth of this theory is evinced further by a 

 circumftance obferved by Mr. J. Hunter, in his 

 Treatife on Venereal Difeafe ; that in a patient, who 

 was inoculated for the fmall-pox, and who appear- 

 ed afterwards to have been previoufly infeded with 

 the meafles, the progrefs of the fmall-pox was de- 

 layed till the meafles had run their courfe, and that 

 then the fmall-pox went through its ufual periods. 



Two fimilar cafes fell under m-y care, which I 

 (hall here relate, as it confirms that of Mr. Hunter, 

 and contributes to illuftrate this part of the theory 

 of contagious difeafes. I have tranfcribed the par- 

 ticulars from a letter of Mr. Lightwood of Yoxal* 

 the furgeon who daily attended them, and at my 

 requeft, after I had feen them, kept a kind of jour- 

 nal of their eafes. 



Mifs H. and Mifs L. two fitters, the one about 

 four and the other about three years old,, were ino- 

 culated Feb. 7, 1791- On the loth there was a 

 rednefs on both arras difcernible by a glafs. On 

 the i ith their arms were fo much inflamed as to 

 leave no doubt of the infection having taken place. 

 On the 1 2th lefs appearance of inflammation on 

 their arms. In the evening Mifs L. had an erup- 

 tion, which refembled the meafles. On the I3th 

 the eruption on Mifs L. was very full on the face 

 and breaii, like the meafles, with confiderable fever. 

 It was now known, that the meafles were in a farm 



houfe 



