CHAP. VII.] MODE OF FORMATION OF GALL-STONES. 383 



Bilicyanin, Choletelin. 



According to the observations of Heynsius and Campbell, which 

 have been confirmed by subsequent observers (Naunyn), these two 

 bodies, which, as we have seen (pp. 328 330) are products of the 

 oxidation of bilirubin and biliverdin, occur in certain of the biliary 

 concretions of man. 



SECT. 3. THE MODE OF FORMATION OF GALL-STONES. 



It is a common, indeed a general belief, among those who have 

 devoted the greatest thought and study to the subject of chole- 

 lithiasis, that all circumstances which tend to hinder the flow of bile 

 favour the formation of gall-stones, and, indeed, that a retarded 

 movement of bile is an essential condition to the formation of these 

 concretions. It is obvious that, cceteris paribus, the liver will be 

 rapidly and effectively drained of its bile in proportion as the 

 respiratory movements, especially the diaphragmatic and abdominal 

 respiratory movements, are active, and conversely that all conditions 

 which tend to limit the respiratory movements will tend to a stasis 

 of bile in the intra-hepatic biliary ducts. The remarkable frequency 

 of biliary concretions in women, as compared with men, has been ex- 

 plained (Naunyn) by the fact that their respiratory movements (costal 

 type of respiration) are less favourable to the compression of the liver 

 and the efflux of its bile than the characteristically diaphragmatic type 

 of respiration in man ; that pregnancy must, of necessity, by impeding 

 to a remarkable extent the diaphragmatic and abdominal respiratory 

 movements, greatly increase the tendency to biliary stasis, a tendency 

 perhaps aided by other conditions which specially affect women, as 

 e.g. tight lacing and sedentary occupations. 



In an investigation carried out, at Naunyn' s suggestion, Schroder 1 in 

 the pathological institute of Strassburg, found gall-stones in 4 -4 p of all 

 male subjects and 20'6 of all female subjects whose bodies were examined. 

 Among 115 female subjects with gall-stones, 99 had with certainty borne 

 children ! 



The frequency with which gall-stones are found in the gall-bladder 

 increases remarkably with age, as is shewn in the annexed table, 

 which exhibits Schroder's results. 



1 Schroder, quoted by Naunyn, Klinik der Cholelithiasis, p. 37. The only reference 

 given by Naunyn is the following, ' Schroder, Strassburger Doctor-Dissert. Wird, 1892, 

 oder 93 publicirt.' 



