176 Dr Drummond on H^mianity to Animals. 



which produce the saUva, but whether its secretion were exactly 

 the same or different, its large size is a pretty good presumptive 

 proof that the quantity of fluid it prepares is not very small. 

 The duct or tube through which the pancreas empties its se- 

 creted fluid, opens into the first of the small intestines; now, if 

 a dog be tied down, and his abdomen be laid open, or, as I have 

 already remarked, if, in vulgar phrase, his belly be ripped up, 

 the hands introduced among his bowels, and the portion of in- 

 testine to which the pancreatic duct goes be slit open, can I, in 

 fairness and truth, trust to any result in this case which may be 

 obtained from observation of the quantity of fluid secreted by 

 the gland during so horrible a process ? T say, it would be un- 

 philosophical to have any such trust, and I would look on al- 

 most all opinions formed on data so unnatural, as unsatisfac- 

 tory and valueless. Magendie thus describes his mode of 

 collecting this fluid : — " I lay bare the orifice of the canal 

 in a dog, I wipe the surrounding mucous membrane with a 

 very fine cloth, and I wait until a drop of liquid passes out ; 

 as soon as it appears, I suck it up with a pipette, an instru- 

 ment used in chemistry. In this manner I have succeeded 

 in collecting some drops of pancreatic juice, but never enough 

 to analyse it according to rule." He also says, " What I 

 have been most struck with in endeavouring to procure pan- 

 creatic juice, is the smallness of the quantity which it forms ; a 

 drop scarcely passes out in half an hour, and I have sometimes 

 waited longer for it. It does not flow more rapidly during di- 

 gestion ; but, on the contrary, it seems slower. I think it is 

 generally more copious in young animals." * At page 212, 

 however, of the same work> the account of the quantity secreted 

 is a little different. " Sometimes," he says, " a quarter of an hour 

 passes before a drop of the fluid springs from the orifice of the 

 canal which pours it into the intestine ;" and in the next para- 

 graph, he observes, that he has seen " the flowing of the pan- 

 creatic fluid take place in certain cases with considerable rapi- 

 dity." The term considerable rapidity is very vague ; but it 

 shows that the secretion was in some cases much more copious 

 than in others, and is a farther proof of the great uncertainty 

 that always must and will attach to experiments of this character. 

 But it may be objected, that a similar exposure of the bile- 

 • Magendie's Physiology, translated by Milligan, ed. 3. p. 457. 



