EXPERIMENTAL E VIDENCE. 555 



collects in the interior ; the second, in making extracts of the intestinal 

 mucous membrane and investigating the digestive properties of such an 

 extract. 



A method of permanently isolating a portion of the intestine was 

 first devised by Thiry. 1 The abdomen of an animal having been opened, 

 a piece of intestine was cut away from its continuity with the main gut 

 without dividing the mesentery. The two ends of the main gut were 

 then brought together and ligatured, so that union of the cut surfaces was 

 brought about, the continuity of the intestine being thus re-established. 

 The isolated portion of the gut was then closed by a ligature at its lower 

 end, while the upper end was sewn into the incision in the abdominal 

 wall, a blind sac being thus formed. Vella 2 modified this procedure by 

 inserting the lower end of the isolated gut also into the abdominal wall ; 

 thus affording two openings for the separated intestine. This operation, 

 performed with due antiseptic precautions, is of constant service at the 

 present day, and is generally described as the establishment of a 

 " Thiry-Vella " fistula. 



Older observers, such as Bidder and Schmidt, 3 had ligatured off from 

 the general tract short lengths of the intestine, and, after replacing them 

 in the abdominal cavity for some hours, had examined the accumulated 

 liquid. 



The chief facts that have been brought to light by these methods 

 are as follows : In the absence of any stimulus, little or no secretion 

 has been obtained, as a rule. Thiry, 4 with mechanical or electrical 

 stimulation, obtained a thin yellowish alkaline secretion, albuminous in 

 character. After food had been taken, although no previous secretion 

 was manifest, some fluid began to form. According to Eohmann, 5 the 

 introduction of starch, sugar, or peptone provokes intestinal secretion. 

 The administration of pilocarpine results, according to Masloff, 6 in 

 secretion. Gamgee, 7 however, found that it was possible to produce 

 considerable increase of other secretions by the administration of 

 pilocarpine without affecting the succus entericus to any extent. This 

 result lie attributed to the fact that probably different regions of the 

 intestine reacted with different vigour to pilocarpine, the lower portion 

 of the intestine secreting a greater quantity than the upper. 8 



With respect to the existence of nervous influences on the secretion, 

 Thiry found no result to come about from stimulation of the vagi. 

 Budge 9 and Lainansky 10 obtained increase of secretion after extirpation 

 of the cosliac and mesenteric plexuses, but Adrian n did not succeed in 

 obtaining this increase. Brunton and Pye-Smith 12 found, in confirmation 

 of an observation of Moreau, 13 that if all nervous connections be severed 



1 " Eine neue Methode den Diinndarm zu isolieren," Sitzungsb. d. Jc. Akad. d. Wissensch., 

 Wien, 1864, Bd. i. 



2 Untersuch. z. Naturl. d. Menscli. u. d. Thiere, 1881, Bd. xiii. 



3 "Die Verdauungssafte und der Stoffweehsel," Leipzig, 1852. 4 Op. cit. 



5 Arch.f. d. ges. Physiol., Bonn, 1887, Bd. ii. 



6 Untersuch. a. (/. physiol. Inst. d. Univ. Heidelberg, 1882, Bd. ii. 



7 "Physiological Chemistry," London, 1893, vol. ii. 



8 That pilocarpine provokes an intense secretory charge in the crypts of Lieberktihn of the 

 large intestine, is manifest from the experiments of Heidenhain (Hermann's "Handbuch," 

 Bd. v.). 



9 Verhandl. d. k. Jc. Leopold-Carol Acad. d. Naturforscher., 1860, Bd. xix. 



10 Ztschr.f. rat. Med., 1866. 



11 Beitr. z. Anat. u. Physiol. (Eekhard}, Giessen, 1863, Bd. iii. 



12 Sep. Brit. Ass. Adv. Sc., London, 1874, 1875, 1876. 



13 Compt. rend. Acad. d. sc., Paris, 1363, Bd. Ixvi. 



