585 



similar changes in passing through the irritated area. Hence the 

 author considers the conclusion to he inevitable, " that the tissues, 

 as distinguished from changes of calibre in the blood-vessels, are 

 the primary seat of inflammation, and that the effects on the blood 

 are secondary results of such derangement." 



The remarkable fact discovered by Dr. H. Weber of Giessen, but 

 observed independently by the author, that accumulation of cor- 

 puscles occurs in the vessels of a part irritated, after circulation 

 has been arrested by a tight ligature round the thigh, furnished the 

 opportunity for careful comparison between the conditions of blood 

 in healthy and irritated parts uncomplicated by the effects of rapid 

 movement. A series of experiments conducted in this way confirmed 

 the conclusion previously arrived at, that the accumulation of the 

 blood-corpuscles was simply the result of their abnormal adhesive- 

 ness. At the same time these experiments brought out the remark- 

 able fact, that mere quiescence of the blood does not give rise to ag- 

 gregation of the red corpuscles within the vessels, unless the tissues 

 are in an unhealthy condition in consequence of irritation. It 

 further appeared that the corpuscles never exhibit greater adhesive- 

 ness within the vessels of an inflamed part, than do those of blood 

 from a healthy part when drawn from the body. Also, the well- 

 known adhesiveness of the white corpuscles within the vessels does 

 not occur, according to the author, unless some degree of irritation 

 is present, and never exceeds that which is always seen in blood 

 outside the body. Hence the inference is drawn, that the tissues of 

 a healthy part exert an influence on the blood in their vicinity, by 

 means of which the corpuscles, both red and white, are preserved 

 free from adhesiveness ; but that in an inflamed part this influence 

 is more or less in abeyance. 



This view has been confirmed by observations made on the wing 

 of the Bat. 



Also the comparison of drops of blood from healthy and inflamed 

 parts in the human subject showed, that so soon as the blood was 

 withdrawn from the vessels, the corpuscles of the former presented 

 precisely the same degree of adhesiveness as those of the latter. 



At the commencement of Section IV., " on the state of the tissues 

 in inflammation," it is stated that " the conclusion arrived at in 

 the latter part of the last section, that blood flowing through an 



