SECT. XXII. 3. 3. AND IMITATION. 203 



ideas in fome meafure Cmilar or imitative of thofe, which we 

 believe to exift in the minds of the perfons, whom we commif- 

 erate or congratulate ? 



There are certain concurrent or fucceflive actions of fome of 

 the glands, or other parts of the body, which are poirefTed of 

 fenfation, which become intelligible from this propenfity to imU 

 tation. Of thefe are the production of matter by the mem- 

 branes of the fauces, or by the fkin, in confequence of the vene- 

 real difeafe previoufly affecting the parts of generation. Since 

 as no fever is excited, and as neither the blood of fuch patients, 

 nor even the matter from ulcers of the throat, or from cutane- 

 ous ulcers, will by inoculation produce the venereal difeafe in 

 others, as obferved by Mr Hunter, there is reafon to conclude, 

 that no contagious matter is conveyed thither by the blood-vef- 

 fels, but that a milder matter is formed by the actions of the fine 

 veflels in thofe membranes imitating each other. See Section 

 XXXIII. 2. 9. In this difeafe the actions of thefe veflels pro- 

 ducing ulcers, on the throat and fkin are imperfect imitations of 

 thofe producing chancre, or gonorrhoea j fince the matter produ- 

 ced by them is not infectious, while the imitative actions in the 

 hydrophobia appear to be perfect refemblances, as they produce 

 a material equally infectious with the original one, which indu- 

 ced them. 



The contagion from the bite of a mad dog differs from other 

 contagious materials, from its being communicable from other 

 animals to mankind, and from many animals to each other ; the 

 phenomena attending the hydrophobia are in fome degree expli- 

 cable on the foregoing theory. The infectious matter does not 

 appear to enter the circulation, as it cannot be traced along the 

 courfe of the lymphatics from the wound, nor is there any fwell- 

 ing of the lymphatic glands, nor does any fever attend, as oc- 

 curs in the fmall-pox, and in many other contagious difeafes ; yet 

 by fome unknown procefs the difeafe is communicated from 

 the wound to the throat, and that many months after the injury, 

 fo as to produce pain and hydrophobia, with a fecretion of in- 

 fectious faliva of the fame kind, as that of the mad dog, which 

 inflicted the wound. 



This fubject is very intricate. It would appear, that by cer- 

 tain morbid actions of the falivary glands of the mad dog, a pe- 

 culiar kind of faliva is produced , which being inftilled into a 

 wound of another animal ftimulates the cutaneous or mucous 

 glands into morbid actions, but which are ineffectual in refpcft 

 to the production of a fimilar contagious material ; but the fali- 

 vary glands by irritative fympathy are thrown into fimilar action, 



and 



