12 APPENDIX. 



are most manifest -that the more sensibility of our organs is called forth, the more is 

 the influence of habit remarkable. Those stimuli, however, which act chiefly and the 

 most exclusively on the contractility of the textures, and those organs principally con- 

 sist in the exertion of this principle of life, have their operations the least impaired by 

 repeated employment ; indeed, in many instances those organs have their functions in- 

 creased and rendered more perfect by frequent exertion. Hence, independently of 

 degree, is the chief difference in the influence of habit on the voluntary organs of the 

 body. 



Of Inflammation, 

 Kote G, 



As the author has taken occasion to give his opinion respecting the proximate cause 

 of inflammation, we shall follow his example, and briefly illustrate the view which we 

 entertained of it, and published in a thesis on rheumatism, in 1815, and more recently 

 in a paper on the functions of the ganglionic nerves, contained in the London Medical 

 depository for May 1822. On these occasions we defined active inflammation to be the 

 result of a morbidly excited state of the gangliul nerves supplying the capillaries of the 

 affected part, or a derangement arising from the unnaturally exalted condition of these 

 nerves on which the functions of the capillaries depend. 



One of the chief inquiries respecting its nature, and physiological relations, is whe- 

 ther this exalted or excited state of these nervous fibrillae is one of simple excitement 

 or no, whether the natural functions of these fibrillie be merely increased above their 

 healthy or ordinary pitch, or whether or no they are also otherwise changed. In the 

 definition, we said morbidly or unnaturally excited, thereby indicating that the func- 

 tions or influence of these nerves are not only simply increased, but also increased dif- 

 ferently from what we observe in a healthy part, from the application of a stimulus* 

 both as respects duration and kind of action. 



1. As respects the duration of this exalted state. In the vascular phenomena dis- 

 played by blushing, or by the application of a gentle stimulus, the effects soon subside 

 after the removal of the exciting cause ; because the nervous influence exerted on the 

 capillaries is simply increased without the mode or habitude of operation being changed. 

 But before we can farther explain the duration of excitement we must secondly inquire 

 into its kind. 



2. When a stimulus or irritant is applied to a part, its action seems to be first upon 

 the ganglial fibrillae supplying the capillaries. The vital influence of these fibrillas 

 being excited, the actions of the capillaries which they supply are consequently increas- 

 ed. There is, however, every reason to suppose, that the increase of this influence is 

 not simple, that it is not only changed in degree, but also modified in kind. The irri- 

 tant seems to impress the nervous fibrillse of the part, or of the system more general!}', 

 in such a manner as to prevent it from returning to its natural state for a very considera- 

 ble time, or even at all ; the excited action is induced, it continues, and the longer it 

 continues the less it is disposed to return to its healthy condition. But wherefore does 

 the excitement continue ? To this we may answer, either because the irritating or ex- 

 citing cause continues to operate by its actual presence, or more frequently because 

 the impression made by it, while it changed the degree of nervous influence, also m6- 

 rlified its state of existence, and kind of operation on the vessels themselves, and the 

 fluids which they contain. It is, therefore, owing to the impression of causes, or 

 changes thereby produced in the kind as well as degree of influence exerted by the 

 yiervons fibrilla?, that we are to impute, 1st, the duration of the excitement ; and 2dlyj 

 the different phenomena which capillary derangements or inflammations present. A 

 few of these phenomena we shall particularize. 



1. Uneasy sensations from its lowest degree until it amounts to acute pain. Uneasy sen- 

 sation alone may be considered one of the primary phenomena following the operation 

 of the exciting cause ; or rather one of the manifestations characteristic of that kind or 

 state of excitement, or deranged influence of the nervous fibrillse, forming the first se- 

 ries of the changes induced in the affected part ; and it may be farther kept up by the 

 subsequent changes induced in the capillaries by the disordered state of the nervous 

 influence, of which state it is itself one of the manifestations. When the uneasy sensa- 

 tion amounts to pain, it may be owing either to the degree of change with which the 

 influence of the nervous fibrill<E, and through it the action of the capillaries are imbued, 



