ADDITIONS AND NOTES TO VOL. II. 515 



different parts of the intestine ; but no definite rule can be laid 

 down on this subject. 



The juice, after the removal, by filtration, of the morphological 

 elements mentioned in the text (see p. 119), contains no trace of 

 albumen, and, therefore, does not coagulate either on boiling or on 

 the addition of acetic acid: alcohol of 85^ throws down white 

 flakes which redissolve in pure water ; their solution is precipitated 

 by acetate of lead, but not by the mineral acids, or by bichloride 

 of mercury : the acetate-of-lead precipitate dissolves readily in 

 acetic acid. 



According to Bidder and Schmidt, the filtered intestinal juice 

 of dogs contains from 3'042 to 3'467 of solid substances. 



Zander found 3 '9% of solid constituents in a specimen of intes- 

 tinal juice containing bile and pancreatic fluid ; amongst the solid 

 constituents there were 2*5 parts soluble in alcohol (glycocholate 

 and taurocholate of soda), and 1/4 parts insoluble in alcohol 

 (taurine, pancreatic fluid, and intestinal juice) ; the unfiltered juice 

 contained 0*8-5- of epithelium, &c. 



Bidder and Schmidt infer from the following observation, that 

 the pure gastric juice must be a tolerably diluted fluid. The 

 filtered intestinal contents, in which there are 3'8-J- of solid consti- 

 tuents, consist not only of the true intestinal juice, but also of 

 gastric juice, bile, and pancreatic fluid; the gastric juice has about 

 the same concentration as the fluid intestinal contents ; but the 

 bile of the dog contains 5^-, and the pancreatic juice 10{f of fixed 

 substances ; hence the intestinal contents could not attain to such 

 a high degree of dilution, unless the true intestinal juice were an 

 extremely aqueous fluid. 



It is obviously impossible to form any certain determination 

 regarding the quantitative relation of this secretion. Bidder and 

 Schmidt calculated from the contentration of the mixed intestinal 

 juice (that, namely, containing bile, gastric juice, and pancreatic 

 fluid), and that of the gastric juice, the bile, and the pancreatic 

 fluid, that the pure intestinal juice must contain about 15 of solid 

 constituents, and that, consequently, that an adult man (weighing 

 64 kilogrammes or 10 stone) secretes in 24 hours about 300 

 grammes of intestinal juice. 



The quantity of the secretion naturally varies according to the 

 period of digestion. In the dog, in which an intestinal fistula wcs 

 formed in the middle of the small intestine, the following remark- 

 able facts were observed by Bidder and Schmidt. This secretion 

 flowed most abundantly from the fistula 5 or 6 hours after a meal; 



2 L 2 



