3 i8 DISEASES Sect. XXXIII. 2. i ©. 



enters the blood-veiTels *, but that the morbid motions of the vef- 

 fels of the fkin around the infertion of it continue to increafe in 

 a larger and larger circle for fix or feven days *, that then their 

 quantity of morbid action becomes great enough to produce a 

 fever-fit, and to affect the ftomach by afibciation of motions ? 

 and finally, that a fecond afibciation of motions is produced be- 

 tween the ftomach and the other parts of the fkin, inducing 

 them into morbid actions fimilar to thofe of the circle round 

 the infertion of the variolous matter? Many more experiments 

 and obfervations are required before this important queftion can 

 be fatisfactorily anfwered. 



It may be adduced, that as the matter inferted into the (kin of 

 the arm frequently fwells the lymphatic in the axilla, that in that 

 circumftance it feems to be there arretted in its progrefs, and 

 cannot be imagined to enter the blood by that lymphatic gland 

 till the fwelling of it fubfides. Some other phenomena of the 

 difeafe are more eafily reconcileable to this theory of fympathet- 

 ic motions than to that of abforption ; as the time taken up be- 

 tween the infertion of the matter, and the operation of it on the 

 fyftem, as mentioned above. For the circle around the infertion 

 is ken to increafe, and to inflame •, and I believe, undergoes a 

 kind of diurnal paroxyim of torpor and palenefs with a fucceed- 

 ing increafe of action and colour, like a topical fever- fit. 

 "Whereas if the matter is conceived to circulate for fix or fc 

 days with the blood, without producing diforder, it ought to be 

 rendered milder, or the blood-vefleis more familiarized to its 

 acrimony. 



It is much eafier to conceive from this doctrine of afTociatcd 

 or fympathetic motions of diftant parts of the fyftem, how it 

 happens, that the variolous infection can be received but once, 

 as before explained - 9 than by fuppofing, that a change is effect- 

 ed in the mafs of blood by any kind of fermentative procefs. 



The curious circumilance of the two contagions of fmall-pox 

 and rneafles not acting at the fame time, but one of them refting 

 or fufpending its action till that of the other ceafes, may be much 

 eafier explained from fympathetic or aflbciated actions of the in- 

 fected part with other parts of the fyftem, than it can from fup- 

 pofing the two contagions to enter the circulation. 



The ikin of the face is fubject to more frequent vicifiitudes of 

 heat and cold, from its expofure to the open air, and is in con- 

 fequenc^ more liable to fenfitive afibciation with the ftomach 

 .1 .my otlicr part of the furface of the body, becaufc their ac- 

 tions have been more frequently thus aflbciated. Thus in a 

 rurfeit from drinking cold water, when a perfon is very hot and 

 -ued, an. eruption is liable to appear on the face in confe- 



quence 



