44 BUCHANAN'S VIEWS ON COAGULATION. [BOOK i. 



very materially, and sacs which normally contain no appreciable quan- 

 tity of liquid may contain large amounts ; this is, for instance, true of 

 the tunica vaginalis testis, the serous sac which envelopes the testis, 

 which is liable to become distended with liquid, the condition being 

 denominated hydrocele. 



The liquor pericardii of man after it has remained for some 

 hours after death in the pericardium, and the liquid of hydrocele, 

 if removed without any admixture of blood, do not coagulate spon- 

 taneously, and they differ in that respect from the liquor sanguinis 1 . 



It was however shewn by Dr Andrew Buchanan of Glasgow in 

 1831 2 , that on adding to ascitic fluid, to serum from the chest, and to 

 hydrocele fluid the liquid obtained by pressing a blood clot in linen 

 cloth, there was produced a coagulum similar to that which separates 

 spontaneously from blood. 



At first Dr Buchanan believed that the blood-colouring matter 

 was the agent present in the squeezed clot, which conferred upon 

 these transudations the property of coagulating. On mixing, how- 

 ever, some peritoneal fluid with the serum of blood, a coagulum was 

 obtained. On subsequently mixing perfectly clear blood-serum 

 with peritoneal fluid and with the fluid of hydrocele, removed after 

 death from the body of the same man, a beautiful pellucid and pretty 

 firm coagulum was obtained. Dr Buchanan remarked, "I repeated 

 the experiment very frequently with serum obtained from the 

 serous cavities of the testis, from the peritoneum, from the cavities 

 of the pleura, and from the pericardium. The result has generally 

 been as I have just described, but not always so." 



These observations of Dr Buchanan on the coagulation of the 

 fluids of serous cavities with other most interesting facts and 

 generalizations were published in 1845 3 . 



"The opinions commonly entertained by physiologists and chemists 

 to which allusion has just been made, are that fibrin has a spontaneous 

 tendency to coagulate; that this spontaneous coagulability is a characteristic 

 property of fibrin, by which it is distinguished from albumin and casein ; 

 and that the coagulation of the blood and of various animal fluids depends 

 on the spontaneous coagulation of the fibrin which they contain. My 

 experiments, on the other hand, shew that fibrin has not the least tendency 

 to deposit itself spontaneously in the form of a coagulum : that, like 

 albumin and casein, fibrin often coagulates under the influence of suitable 



1 The liquor pericardii of the dog and of the horse does not coagulate spontaneously ; 

 that of the rabbit coagulates, however, with readiness. 



2 "Contributions to the Physiology and Pathology of the Animal Fluids, containing 

 Experiments and Observations on the effects of certain substances upon the blood; 

 on the coagulation of the blood ; on the difference between membranous and sanguineous 

 serum; on the formation of the buffy or inflammatory crust; on the formation of pus; 

 and on the process of sanguification, by Andrew Buchanan, M.D., Junior, Surgeon to 

 the Glasgow Infirmary." London Medical Gazette, vol. xvm. (2nd vol. for session 1835 

 36), p. 50. 



a "On the Coagulation of the Blood and other fibriniferous liquids, "London Medical 

 Gazette, 1845, Vol. i. (New Series) p. 617. (Communicated to the Glasgow Philosophical 

 Society, 'Feb. 19, 1845.) Reprinted in the Journal of Physiology, 1879. 



