xxvi INTRODUCTION TO fiOJE 



In this performance too, he contends againft the advocates for fed- 

 atives. Opium, he declares, has a flimulant operation ; colds or ca- 

 tarrhs are produced by heat fucceeding to cold, and not vice verfa ; 

 and extends his laws of animation to the vegetable creation. 



In fhort, he concluded there was in the medullary nervous matter, 

 and niufcular folid of living bodies, which have been generally called 

 the nervous fyflem, a property by which they could be affected by 

 outward agent?, as well as by their own functions, in fuch away as to 

 produce the phenomena peculiar to the living (late. This capacity of 

 beinc acted upon is termed excitability, and the agents are all denom- 

 inate djlim ulant s, while the effect produced by the operation of flimu- 

 lants upon excitability is called excitement. 



Excitement is terminated in two ways. i. By the exhauftion of 

 excitability, through the violence c-r continuance of flimulus, which 

 is called irvMrccl debility, 2. By the accumulation of excitability, 

 through deficient Itimulus, which is termed direcl debility. Between 

 the two extremes of indirect and direct debility are experienced both 

 health and dileafe6 of the fthenic kind, or thofe febrile complaints (py- 

 rexia;,) accompanied with what has been called phlogiftic diathefis, 

 wherein, though the excitement confiderably exceeds the healthy rate, 

 ftill it does not reach the limits of indirect debility. 



Stimuli lofe their efficacy after long and frequent application ; but 

 even then the excitability, exhaufled in relation to one itimulus, is ca- 

 pable of being acted upon by another. 



Therefore, the waile of excitability, after exhauftion of one flimu- 

 lus after another, is very hard to be repaired, by reafon of the difficul- 

 ty of accefs to frefh ftimuli to work upon the languishing excitability ; 

 which, by being applied ftrong at firft, and gradually weakened after- 

 wards, anfwers the purpofe ; and alfo the fuperabundant excitabili- 

 ty left by fubduction of one flimulus after another, produces fuch an 

 excitable condition of the fyflem, that much nicety is requifite to wear 

 it gradually away by application of very weak flimuli at firft, and by 

 degrees flronger and flronger, until the aceuilomed ones can be com- 

 fortably borne. According to the Brunonian Doctrine difeafes ap- 

 pear under various modifications, as exhibited in the table below. 



Thus they may be, 



1. Univerfal, fuch as primarily affect the whole conftitution, as fe- 

 vers, Zlq.. 



2. Local, where, from limited morbid affection, a particular part 

 labours, without difordering the intire habit ; as trifling wounds, 

 phlegmons, occ. 



5. Loeo-univcrial, when, from a local affection, the whole body is 

 eventually brought into a dii'eafed condition ; as in lues originat- 

 ing from chancre, fmall-pox from inoculation, &c. 



4. Tlmverfo-local ; as if after a general ailment any particular part 

 or organ is affected in a fecondary way ; as the eruptions of exan- 

 ; matous pyrexia, fyphilitic blotches, &c. 



Anf' each of thefe forms of difeafes muff coniiil either in, 



l. I >ire& debility ; as in fcurvy, hunger, cold, &c. 



2, StheiH- 



