352 The Viscosity of Bile [April-July. 



the specific gravity, and the length and diameter of the capillary, 

 these factors enable the experimenter to calculate the coefficient of 

 the viscosity, Moreover, in order that the latter convey a clear 

 meaning to the reader, it may be compared with the coefficient of the 

 viscosity of distilled water heated to 37° C. which possesses the 

 numerical value 4700. The viscosity of bile, as well as that of any 

 other fluid, may therefore be expressed in terms of multiples of this 

 coefficient. 



The present determinations have been made with ox bile ob- 

 tained f roni the animals at slaughter by incising the gall-bladder, as 

 well as with bile collected in the same manner from dogs during 

 ether narcosis.^ As the amount procured from a single animal was 

 generally very small, the specific gravity was tested with the aid of 

 pycnometers containing 5 c.c. and less of fluid. The diameter of 

 the capillary measured 0.41 mm. ; its length, 29.0 cm. These tests 

 were made at a temperature of 37° C. 



Table i proves first of all that ox bile possesses a viscous resist- 

 ance which is very much slighter than that of dog bile. The co- 

 efficients here found vary between 2260 and 2718, and show the 

 average value of 2511 ; and hence, ox bile presents a viscosity which 

 is only 1.8 times greater than that of distilled water at 37° C. More- 

 over, when compared with the coefficient for the circulating blood 

 of the dog, which is 950, it is seen that this body-fluid possesses a 

 viscous resistance only about one-third as great as that of blood.^ 

 This result agrees perfectly with the values for the specific gravity, 

 which vary between 1.0178 and 1.0207, and also with the fact that 

 ox bile contains only traces of mucin. 



The experiments with dog bile have given values ranging be- 

 tween 541 and 1074, and the average coefficient 723. Clearly, there- 

 fore, this fluid possesses a viscosity which is much above that of 

 ox-bile and, in a slight measure, also above that of ordinary blood. 

 Compared with distilled water at 37° C, it exhibits a viscous resist- 

 ance 6.5 times greater and equal to that of a "thick" type of blood. 



2 On account of rather stringent laws intended to govern the Performance 

 df autopsies, I have not been able to gather very satisfactory data regarding 

 normal human bile. It seems best, therefore, to postpone the publication of these 

 data until a later date. 



3 Burton-Opitz : Pflüger's Archiv, 1900, Ixxxvi, p. 406. 



