ADHESION. 



51 



is rendered particularly evident when the 

 lymph is submitted to the action of boiling 

 water ; it dissolves almost completely in a warm 

 solution of caustic potash, though less promptly 

 than thickened albumen, but more rapidly 

 than fibrine. 



This matter, which is probably the same with 

 that by which all parts of the body are nourished 

 and preserved, but in the case before us secreted 

 in increased quantity and preserving a strong 

 tendency to coagulate, has nothing in it which 

 is necessarily opposed to the healthy action of 

 the animal economy. In fact we may consider 

 exudation as a nutrition, much exalted by in- 

 flammatory action, which is itself only an 

 exaltation of the vital properties. 



We may admit four periods or states of 

 change to which tin's material which consti- 

 tutes the medium of adhesion is subject 

 a first, the period of development; a second, 

 a period of increase ; a third, that of organi- 

 zation ; and a fourth, that of mutation ; in 

 which it is changed into a cellular tissue. 



In the first period, we find that in twenty- 

 four, and sometimes even in nineteen hours 

 after we have irritated a serous membrane, the 

 pleura of a dog, or of a rabbit for instance, that 

 this membrane is much injected, and that there 

 has been formed upon its surface an extremely 

 thin, pulpy stratum, which may very easily be 

 removed : the second period commences when 

 this exudation has assumed a membramform 

 appearance, and is characterized by an aug- 

 mentation of thickness and of density : the third 

 period is characterised by still greater density 

 and the presence of vessels. Stoll believed that 

 these membranes might become organised in 

 twelve, nine, or even eight days after the inva- 

 sion of the disease. Home believed that 

 vessels might appear in twenty-four hours. 



In the fourth period, the membrane loses 

 some of its thickness, and every day assumes 

 more and more of the appearance of cellular 

 tissue ; and when perfected, there is not only 

 identity of appearance between cellular tissue 

 and these membranes, but also, according to 

 Laennec,* identity of use, and even of disease, 

 except that this tissue very rarely contains adi- 

 pose matter, f 



Nothing in our subject is more curious or 

 more important than the organisation of these 

 membranes ; their vessels are thin, delicate, 

 and similar to those of the pia mater ; their 

 form and their direction are extremely simple ; 

 they are not tortuous, and they proceed, usually, 

 in fasciculi, almost like the lymphatics of the 

 extremities. We may easily convince ourselves 

 that their formation is sometimes very prompt, 

 by the perusal of the following case. A por- 

 tion of strangulated intestine, which, after the 

 incision of the herniary sac, did not present 

 many bloodvessels, was examined after the 

 death of the individual, which occurred in 

 twenty-nine hours after the operation, by Sir 

 Everard Home : he found the portion of in- 



* De 1' Auscultation Mediate, tom.ii. p. 293. 

 t Laennec states that he has " quelquefois " seen 

 fat developed in these cellular laminae. Loc. cit. ED. 



testine which had been strangulated profoundly 

 inliamed, and covered in many points by a 

 " layer of coagulable lymph:" this intestine was 

 injected with very fine size, and two small 

 bloodvessels were found passing along through 

 the new membrane into which the injection 

 had penetrated. 



According to Laennec* we may observe the 

 following phases in the organisation of these 

 membranes. 



The rudiments of bloodvessels are at first 

 presented under the form of striae of blood, 

 which are more voluminous than the vessels by 

 which they are to be succeeded. The blood 

 appears to have penetrated into the tissue of the 

 membrane, as if pushed by a strong injection; 

 yet in examining the points of the membrane,on 

 which the layer of" coagulable lymph " is depo- 

 sited, we find no destruction, nor any orifice of 

 a vessel, but only spots of blood. Soon, ac- 

 cording to Laennec, "these lines of blood take 

 a cylindrical form, and ramify in the manner of 

 bloodvessels, still preserving a considerable 

 diameter. If, at this epoch, we carefully ex- 

 amine them, we find that these vessels have an 

 external coat which is soft, and formed of blood 

 scarcely concrete, to which they owe their 

 colour. After having incised this coat, we 

 withdraw a sort of mould, or rounded fasci- 

 cular body, whitish and fibrous, evidently 

 formed of concrete fibrine, and of which the 

 centre appears perforated and permeable to the 

 blood. [Jowever small be the canal, it is these 

 fibrous fasciculi which should, by thinning, form 

 the tunics of the bloodvessels." 



These delicate observations have not, so far 

 as I know, been confirmed by other observers : 

 those authors who have spoken of newly deve- 

 loped vessels, among whom we may name 

 Hunter, Monro, Soemmering, do not speak of 

 this mode of development. Hunter and Home 

 explain it differently; they say there is at first 

 a formation of small ampullae, containing only 

 a colourless fluid : second, a union of these 

 ampullae, and production of a vascular net- 

 work, not yet supplied with blood : third, an 

 inosculation between the newly developed 

 vessels, and those of the inflamed membrane, 

 and next the ingress of blood. Beclard was of 

 the same opinion.f Gendrin thinks that the 

 new vessels are developed by the action of the 

 primitive vessels ; he says, " that the blood is 

 excreted by the adjoining capillaries, opening 

 into the soft and fibrinous tissue deposited in 

 the inflamed part; this blood becomes concrete, 

 and the vascular impulsion, a tergo, being con- 

 tinued, new blood is pushed into it and hollows 

 it. Thus the little vascular rudiment is pro- 

 longed into an irregular, flexuous, and unequal 

 stria, which meets another and unites with it, 

 continuing in this way to prolong itself into 

 the least resistent portion of the fibrinous de- 

 position. "\ 



To some extent the opinions of Laennec and 



* Loc. cit. 



t Anat. Generate, p. 195. 



| Hist. Anat. des Infhun. torn. ii. 6 1 >')3 and 

 1571. 



E 2 



