THE BLOOD. 87 



finally, they dissolve, and all traces of them disappear. These 

 successive changes are all produced in the course of a very 

 few hours : the exact period, however, varies with the tem- 

 perature of the atmosphere and actual condition of the blood 

 when extracted from the system. 



MODIFICATIONS THE RESULTS OF DECOMPOSITION OCCUR- 

 RING IN BLOOD WITHIN THE BODY AFTER DEATH. 



The changes which we have described as occurring in blood 

 abandoned to itself without the system, take place likewise 

 in the red corpuscle of that which is contained within the 

 body after death, and this even with a greater degree of 

 quickness than in the former case ; the time, however, 

 bears a relation to atmospheric conditions, to temperature, 

 as well as, especially, to the nature of the malady to which 

 the patient has succumbed. If the affection which has oc- 

 casioned death be of a nature to exhaust profoundly the vital 

 powers, if it be a chronic disease of long duration, as a typhoid 

 fever, the period requisite for the production of these changes 

 will be very short ; so brief, indeed, that the alterations may 

 be detected in the corpuscles almost immediately after the 

 extinction of life. It is of much importance that the changes 

 resulting from decomposition, and which occur in the dead 

 body, should not be confounded with real and pathological 

 alterations of the red corpuscles. 



CAUSES OF INFLAMMATION. 

 Exciting Cause. 



The fact which has been alluded to in the preceding 

 pages, of the accumulation of the white and red corpuscles 

 in the tongue and web of the frog as a consequence of the 

 application of irritation, bears a close relation to the phe- 

 nomena of inflammation, and shows that the exciting cause 

 of inflammation, whatever it may be, such as a blow, expo- 

 sure to cold, burns, scalds, or the application of irritating sub- 

 stances, acts usually through the medium of the nervous 



