THE BLOOD. 113 



the other blood globules, would doubtless all become destroyed 

 and removed in the course of a few days, and this especially 

 if the blood corpuscles were different from those of the 

 animal from which the transfusion had been practised. 



The Blood in an Ecchymosis. 



When a part is bruised to such an extent as to occasion 

 the rupture of the minute capillaries and vessels contained in 

 it, blood is effused constituting an ecchymosis. The same 

 effect sometimes takes place, not as the result of the applica- 

 tion of external violence, but from disease, the solid tissues 

 and that of the vessels especially giving way through debility, 

 and permitting the escape of their contents, as occurs in 

 malignant and putrid fever, in Purpura Hcemorrhagica, in 

 scurvy, and in bed-sores. 



If a portion of the effused blood be removed from the 

 bruise and examined microscopically, the globules will be 

 observed to be wrinkled and irregular in form, corresponding 

 with and depending upon internal changes in the condition 

 of the blood effused, and which are indicative of the occurrence 

 of decomposition ; certain external appearances will be noticed, 

 the skin will appear mottled, different hues of black, green, 

 and yellow being intermixed and varying in intensity until 

 the period of their total disappearance. 



The phenomena of decomposition precede the disappearance 

 of the red corpuscles which are removed from the seat of 

 injury, and are returned to the circulation in a state of solu- 

 tion. Now were the opinion true that the blood corpuscles 

 are applied directly to the formation of new tissue, a very 

 different result to the decomposition and solution of the 

 globules, to which we have referred, would be anticipated, 

 and we should expect to find that the extravasated blood had 

 given rise to an adventitious and organised product, an event 

 to which ecchymoses never lead. 



