150 PROGRESS OF VETERINARY SCIENCE AND ART. 
where pancreatic juice mixed with the chyme, and that then 
it was capable of absorption. In higher animals the duct of 
the pancreas opens into the duodenum near the pylorus, and 
the fats are changed higher up than in the rabbit. 
Bernard gives an historical sketch of the writings on the 
pancreas and its secretion, and the most important are those 
of De Graaf, Magendie, Tiedemann, and Gmelin, and of 
Leuret and Lassaigne. All these gentlemen collected the 
pancreatic juice ; Tiedemann and Gmelin obtained it from 
the dog and sheep, and they said the pancreatic juice was a 
complex fluid very different from saliva, having an acid re- 
action, and containing albumen. ' Magendie, who was one of 
ihe first to collect the fluid, had determined its alkalinity, 
and proved it was coagulable by heat. But nothing was abso- 
lutely known of the properties of pancreatic juice before 1846, 
when Bernard undertook his experiments upon it. 
The pancreas is not always single, and there is often a 
detached portion, or “lesser pancreas,” generally behind the 
anterior mesenteric artery. Bernard says that there are 
always two ducts, but the smaller one is sometimes obli- 
terated. Several woodcuts in M. Bernard’s work illustrate in 
a most complete manner the arrangement of the two ducts, 
and the method adopted to procure the secretion by fixing 
glass or silver tubes in the pancreatic duct. The abdomen is 
opened in the right hypochondriac region, and the tube once 
fixed is made to project through the external wound, and 
a bladder is tied on to it. A stopcock is attached to the 
bladder, so that the latter may be readily emptied as fast as 
it is filled. Many precautions must be taken to ensure suc- 
cess and avoid sources of fallacy. The sensibility of the 
pancreas is so great, that the secretion is easily modified or 
completely arrested for an indefinite period. The pancreatic 
juice is really to be studied in its normal and in its abnormal 
conditions ; and when the operation performed to procure it 
does not affect the animals much, and the fluid is pure, we 
find that it is secreted at intervals, beginning when digestion 
commences, and continuing some time after the gastric juice 
has ceased to flow. Blood is more abundantly supplied to 
the gland when the juice begins to flow; and when the organ 
is at rest it loses its pinkish or crimson colour, and becomes 
pale. 
Circumstances affecting the digestive function in general 
have a special influence on the pancreas, and modify its secre- 
tion ; such is not the case with the salivary glands and their 
products. The pancreatic juice may, like every other secre- 
tion, be found to contain adventitious substances that have 
