3 1 o DISEASES Sect. XXXIII. 2.3, 



The heat Is occaficned from the increafed fecretions either of 

 mucus, or of the fibres, which produce or elongate the vefTels. 

 The red colour is owing to the pellucidity of the newly formed 

 veflels, and as the arterial parts of them arc probably formed be- 

 fore their correfpondent venous parts. 



3. Thefe new motions are excited either from the increafed 

 quantity of fenfation in confequemce of greater fibrous contrac- 

 tions, or from increafed fenfibility, that is, from the increafed 

 quantity of fenforial power in the moving organ. Hence thev 

 are induced by great external ftimuli, as by wounds, broken 

 bones ; and by acrid or infectious materials ; or t>y common 

 ftimuli on thofe organs, which have been fome time quiefcent ; 

 23 the ufual light cf the day inflames the eyes of thofe, who have 

 been confined in dungeons ; and the warmth of a common fire 

 inflames thole, who have been previoufly expofed to much cold. 



But thefe new motions are never generated by that pain, 

 which arifes from deieel; of Hamulus, as from hunger, thirds 

 cold, or inanition, with all thofe pains, which are termed ner- 

 vous Where thefe pains exift, the motions of the affected part 

 are leflened ; and if inflammation fucceeds, it is in fome diftant 

 oarts ; as coughs are caufed by coldnefs and moiflure being long 

 applied to the fcti •, or it is in eonfequence of the renewal of the 

 ftimulus, as of heat or food, which excites our organs into 

 stronger action after their temporary quiefeence j as kibed heels 

 after walking in fnow. * 



4. But when thefe new motions of the vafcular mufcles are 

 exerted with greater violence, and thefe veflels are either elon^ 

 ted too much cr ;, new material is fecreted from their 

 extremities, which is of various kinds according to the peculiar 

 animal motions of this new kind of gland, which fecretes it ; 

 fuch is the- pus Iuudabile or common matter, the variolous mat- 

 ter, venereal matter, catarrhous matter, and many others. 



5. Thefe matters are the product of an animal procefs ; they 

 are fecreted or produced from the blood by certain difeafed mo- 

 tions of the extremities of the blood-vefTels, and are on that ac- 

 inic all of them contagious ; for if a portion of any of thefe 



is tranfrnitted into the circulation, or perhaps only inferted into 

 she fcin, or beneath the cuticle of a healthy perfon, its ftimulufl 

 in a cer:a-;n t reduces the fame kind of morbid motions, by 



which iricic was produced :, and hence a (imilar kind is genera- 

 ted. Sec Sea. xxxix. & 1. 



6. lr 'varkabk., that many of thefe contagious ma ire 

 capable of producing a fimUsi difeafe but once ; as the fmalli 

 p^x and no | } fuppofe this is true of all thofe conta- 



b are aneoutly cured by nature in a cc 



taiu 



