Tissue of the Tongue in Inflammation. 



391 



pins stuck into the cork ring. As thus displayed, the smooth surface of the 

 organ of course rested on the glass, the papillary surface looking upwards. 



To expose the submucous tissue, Cohnheim found it necessary to divide 

 the mucous membrane to the extent of an eighth of an inch ; by doing so 

 he was able to obtain a sufficient surface for microscopical examination, 

 in which, if care was taken to keep it constantly moist with serum and to 

 avoid undue stretching, the circulation could be observed for many hours. 

 Although, as compared with the one to be immediately described, the 

 method was imperfect, it was much superior to any which had been em- 

 ployed before for the study of the textural changes which are associated 

 with the process of inflammation. 



In the stratum of tissue thus exposed, the objects which first attract 

 attention are, it need scarcely be said, the arteries, veins, and capillaries, 

 and the rapidly circulating blood. In addition to these, various fibrous 

 structures present themselves, namely striped muscular fibres, single or 

 in groups, some entire, others broken; nerves, each consisting of a 

 variable number of dark-bordered nerve-fibres, bundles of white fibrous 

 tissue, and very numerous single fibrils. In the spaces between these 

 structures a number of bodies are seen scattered without apparent regu- 

 larity in the fine transparent membrane of areolar tissue. With reference 

 to these bodies, which were first described by Cohnheim, and constituted 

 the principal subject of the paper now referred to, he remarks that although 

 they differ considerably in form and appearance from the fixed elements 

 of areolar tissue elsewhere, they can only be regarded as " connective- 

 tissue corpuscles." 



Cohnheim found that when this tissue, immediately after having been 

 exposed in the manner above described, was observed continuously for 

 many hours under the microscope, the circulation became much accele- 

 rated, and the vessels (veins and arteries) became dilated. Soon the 

 dilatation of the arteries diminished, while the motion of the blood became 

 slower, especially in the veins of which the diameter was still larger than 

 in the natural state. In a short time the colourless corpuscles began to 

 hug the walls of the veins, and soon after emigration set in with great 

 vigour. As this went on, it was seen that in numerous capillaries stasis 

 was either commencing or complete, a state of things which rapidly led 

 to diapedesis, affecting both capillaries and veins. 



These facts having been ascertained, and being moreover in complete 

 accordance with what Cohnheim had himself described in inflamed parts 

 elsewhere, it remained to inquire what part the fixed elements played in 

 the active changes going on around them. Eor our present purpose 

 it is sufllcient to state that Cohnheim concluded that they took no part 

 whatever in those changes ; and he used this fact in support of his general 

 position, that fixed elements of tissues do not participate in any inflam- 

 matory processes of which those tissues may be the seat. 



But since 1868, as is well known, Oohnheim's conclusions on this sub- 



