PHYSIOLOGY. 



actions.; since the affections of the body 

 clearly act on the mind in many other 

 ways than through the medium of sensual 

 perceptions. The infinitely varied modi- 

 fications, which the four principles ad- 

 mit of, show immediately with what lati- 

 tude our notions concerning 1 health 

 should be formed. Hence arises the dis- 

 tinction of temperaments ; that is, the dif- 

 ferent manner in which the living 1 solid is 

 affected by stimuli, particularly of the 

 mental class, the different aptitude for 

 such impressions, and the greater or less 

 facility with which these stimuli may 

 themselves be excited. There is such 

 great variety of degrees and combinations 

 of temperaments, that a wide field is 

 open for those who wish to employ them- 

 selves in dividing' and arranging them. 

 The common division is sufficient for our 

 purpose ; it comprehends the sanguine- 

 ous, which is very easily but slightly af- 

 fected by stimuli; the choleric, which is 

 easily and strongly excited ; the melan- 

 cholic, which is slowly but deeply mov- 

 ed ; and the phlegmatic, which" is the 

 slowest of all in admitting the impres- 

 sions of exciting causes. Together with 

 these distinctions, there are numerous 

 differences of bodily formation, of diver- 

 sity in the proportion and connection of 

 parts, as well as in the energy relative to 

 certain organs, accompanying each tem- 

 perament, which cannot be particulariz- 

 ed here, without entering too much into 

 detail. 



Each individual has a particular man- 

 ner of being, which distinguishes his tem- 

 perament from that of every other, to 

 which, notwithstanding, it may bear a ve- 

 ry strong resemblance. These indivi- 

 dual temperaments, the knowledge of 

 which is of no small importance in the 

 practice of physic, are called idio-syncra- 

 sies. 



There are many both predisposing and 

 occasional causes, which hav-e an opera- 

 tion in producing this diversity of tempe- 

 raments : as hereditary disposition, habit 

 of body, climate, diet, religion, culture, 

 luxury, &c. 



For the account of the various races of 

 mankind, see the article MAX. 



Jldvanced Jlge and Decay. Cessation of 

 the menses in women, which is occasion- 

 ally accompanied by the production of a 

 beard ; an indisposition to venery in the 

 male sex ; and, in both, a peculiar dry- 

 ness, and sensible decrease in the vital 

 powers, are the signs of approaching old 

 age. ' The body now diminishes, and los- 

 es the power it had acquired; the de- 



crease following the same progression as 

 the growth, and occupying about the 

 same space of time, when no accident 

 hastens the approach of death. The 

 whole volume of the body diminis'u.-s, 

 the skin wrinkles, particularly in the 

 forehead and face; the hair turns grey, 

 and organic action becomes languid. 



The decay of the body is evidenced by 

 an increasing dulness both of the external 

 and internal senses, necessity of longer 

 sleep, and general torpor of all the func- 

 tions. The hair grows white, and falls off, 

 the teeth drop from their sockets, the 

 cartilages ossify, all the organs become 

 hard, and the fibres more dry and con- 

 tracted. The head is no longer support- 

 ed by the neck, nor can the legs sustain 

 the trunk; nay, the bones themselves, 

 the foundations of the machine, partake 

 of the general decay. On these pheno- 

 mena we may observe, that the animal or 

 exterior life ceases first, the senses fail in 

 succession, and then the functions of the 

 brain cease. The cessation of the loco- 

 motive and vocal powers follows as a ne- 

 cessary consequence. Here, then, the 

 old man is dead to all surrounding ob- 

 jects, but his organic life still subsists ; so 

 that this state is analogous to that of ute- 

 rine existence, where the life is nearly of 

 the vegetable kind. Thus, the body gra- 

 dually dies, life is extinguished by suc- 

 cessive shades, and death is only the last 

 term in this succession of degrees. We 

 arrive now at the conclusion of physiolo- 

 gy ; death without disease ; which is the ob- 

 ject of all medicine, and the causes of 

 which are necessary and inevitable. It 

 is no more possible for us to avert the 

 fatal term, than to change the laws of 

 nature. 



The phenomena of death consist in a 

 coldness of the extremities, gradually 

 mounting to the trunk; dimness of the 

 eye ; feeble, slow, and irregular pulse ; 

 respiration performed at longer intervals, 

 and terminated at last by a strong expira- 

 tion. In experiments on animals, a strug- 

 gle is observed about the heart, and the 

 right ventricle and auricle are found to 

 survive the opposite cavities for a short 

 time. That death has taken place Ls 

 shown by coldness of the body, combin- 

 ed with rigidity ; flaccidity of the cornea, 

 relaxed state of the anus, lividity of the 

 back, and a certain cadaverous odour. 

 When all these circumstances are com- 

 bined, there will scarcely be any oppor- 

 tunity for remarking the uncertainty of 

 the signs of death. 



Altixough the weakness of the thread 



