282 Dr. Waller on some Tissues of the Animal Frame, 



to so many pebbles or marbles over which a stream runs 

 without disturbing them. Another arrangement of them in 

 the capillaries is shown in fig. 4, where the vessel is occupied 

 solely by these spherules. This is only to be found near 

 the borders of the tongue, where we may suppose that the 

 greatest irritation exists. The spherules are there found 

 to be quite motionless, and not a single red particle can be 

 detected at any point of the vessel, which, in the case in ques- 

 tion, was followed for a considerable length. The corpuscles, 

 which are transparent, are occasionally seen to be granulated. 

 It appears to be very doubtful whether this corpusculation (if 

 I may be allowed the expression) is an invariable accompa- 

 niment of all cases of irritative congestion or inflammatory 

 action, as has been maintained. As far as I have been enabled 

 to judge, the corpusculation only occurs after n rapid circula- 

 tion has existed for some time in the vessels of the part irri- 

 tated ; but if the congestion and stagnation occur quickly, 

 this collection of corpuscles is not to be seen, which would 

 appear as if they required to be eliminated from a consider- 

 able mass of blood. 



4. Extra Fibrination of the Capillaries. — Under this term 

 I denominate another effect produced by increased influx 

 of blood, which, if not so striking as the collection of the 

 corpuscles, is still more constantly observed. It consists 

 in a kind of condensation of the tissue on the exterior of 

 the vessel, and appears to be produced by the exudation 

 of the fibrinous parts of the blood, from increased pressure 

 exerted by the blood on the capillaries. While thin is 

 taking place the vessel is less distinctly seen ; minute globular 

 forms may be perceived in this condensed tissue, consisting 

 probably of particles of fibrine. I have already shown in a 

 former paper upon the structure of vapours, &c, the great 

 tendency which liquids have to assume a globular shape. It 

 would be convenient to apply some term, such as I have used 

 above, to distinguish this action. Sometimes, as in fig. 5, 

 these globules are very distinctly seen. 



5. Extravasation of Blood.— When this occurs, the whole 

 surface of the tongue becomes covered with numerous spots of 

 blood, similar to those which appear on the human body. It 

 appears to take place more frequently in the glands than at 

 other places, and the blood appears to be affected at their ex- 

 terior surface. Generally the current of blood is stationary at 

 the point of rupture and in the adjoining vessels. The ap- 

 pearance presented by the vessel at the ruptured point is 

 shown in fig. 6. There is found a conical tumour projecting 

 from the sides of the vessel ; and at its extremity are seen a few 



