I N T 



otlicr knowleJgc dtipends : this certainty every one finds to 

 bo fo great, tliat he cannot imagine, and therefore cannot re- 

 quire, a greater. See Judgment, Knowledge, Demos- 



STKATION, &c. 



INTUITIVE EvinENTE, is that which rcfults from in- 

 tuition. Dr. Campbell cliftingiiinies different forts of in- 

 tuitive evidence : one refulting purely from intellcdiion, or 

 that faculty whicli others have called intuition ; another 

 kind arifmg from confcioufnefs ; and a third fort from that 

 Dcvv-named faculty common fcnfi, which this ingenious. writer, 

 as well as fevcral others, contend to be a diiUnft original 

 fourcc of knowled^ ; whilll others refer its fuppofcd office 

 to the intuitive power of the underflanding. Campbell's 

 Rhetoric, vol. i. book i. chap. 5. 



INTURKI, in Gcngraphy, a town of Lithuania, in the 

 palatinate of \Vilna ; 18 miles N. of Wilna. 



IN TUIIN, among Wn-flhrs, is when one puts his thigh 

 between thofe of his adverfary, and lifts up his thigh. 



INrUSSUPCEPTION, or Introscsception, a terra 

 in Surgery, exprelTive of a very dangerous difeafe, which 

 arifes from the pafl'age of one portion of an intcftinc into an- 

 other." The word is derived from intus, within, and/ufcipio, 

 to receive. The diforder is alfo frequently named a vohu- 

 lus. It happens moft commonly in tlie liril fifteen years of 

 life, older perfons not being nearly fo fubjecl to the afflic- 

 tion. 



When the upper part of an inteKine pafled into the lower, 

 that is to fay, when the introfiifception was downwards (as 

 generally happens), Mr. Hunter called the cn{e prcgrr/Jive ; 

 bat when the difeafe arofe from the paflage of a lower por- 

 tion of bowel into an upper one, he named this example 

 rctrograJs. 



Introfufceptions are proibably far more frequent cafes than 

 many fuppofe, and numerous infants and young fui5Jccls, no 

 doubt, are viftims to the difeafe, without its e.xiilence being 

 in the leall fufpeded. The affeftion may indeed be lefs fe- 

 vere ; and we are informed, that the greateft part of three 

 ' hundred children who died, either of worms, or during den- 

 tition, at the Kopital de la Salpetiiene, and were examined 

 by M. Louis, had two, three, four, and even more volvuii, 

 without any inflammation of the parrs, or any circumllances 

 leading to a fufpieion that thefe affections had been injurious 

 during lit?. M. Louis thought fuch cafes proved tliat an 

 introfufception might be formed, and deftroyed again, by the 

 mere action of the bowels ; an opinion whicli is confirmed 

 by the obfervation of Dr. Baillie, that " in opening bodies, 

 particularly of infants, an intus-fufceptio is not unfrequently 

 foupd, which had been attended with nomifchief ; the parts 

 appear perftftly free from inflammation ; and they would 

 probably have been eafily difentangled from each other by 

 their natiiralpenllaltic motion." See Mem. de I'/^cad. de 

 Chiriirgie, 4to. edit, torn iv. p. 22g, and Baiilie's Morbid 

 Anatomy, ad edit. p. 162. 



Mr. Hunter thought that the manner in which an intro- 

 fufception may be formed, is, by one portion of a loofe in- 

 teilme being contradled, and the part immediately below re- 

 laxed and dilated ; under wliich circumftanccs the contrafted 

 portion (lips a little way into that which is dilated. He 

 fuppofed alfo, that this change was not the effeft of any ac- 

 tion- in either portion of intcftine, but might be the con- 

 . fequence of fome additional weight in the upper part of the 

 bowel. How far the periitaltic motiori, by pufliing the con- 

 tents on to the contradkd parts, might force thefe into the 

 relaxed ones, Mr. Hunter was unable to determine, 

 though he was inclined to think that nothing of the kind 

 could happen. 



Suppoling the foregoing explanation to be true, an acci- 



I N T 



dental introfufception rray take' place eitiicr upwards or 

 downwards ; but if a continuance or an increafe of the dif- 

 eafe really arifes from the aftion of the inteftine, it can 

 only be when the cafe is downwards. Yet this does not ex- 

 plain thofe inftanccs in which a confidcrable portion of intef- 

 tine is carried into the gut below. In order £0 underlland 

 thefe, the different parts which form the introf'.:fception muft 

 be confidcrcd. We mud rccollcft that every introfufception 

 is compofed of three folds of inteftine ; ^>^^. the inrer, which 

 paffes down, and being reflecled upwards, forms the/econe/, 

 or jBiK-rte.' portion, which, being refiefted down again, makes 

 the Mrei, or containing jiart. ■ This latter is the outermoft, 

 and is always in its natural pofition. 



According to Mr. Hunter, the outward fold is the only 

 one which is active, the inverted portion being perfectly 

 paffive, and fqueczed down by the outer, which inverts more 

 of itlclf, fo that tJ;e angle of inverfion, in the cafe, is always 

 at the angle of refleftion of the cuter into the middle, or 

 inverted fold, while the innermoft is drawn in. Hence we 

 may fee how an introfufception, once begun, may have any 

 length of gut drawn into it. 



Theexttrnal portion ading upon the other folds in the fame 

 way as upon any extraneous matter, will, by its perillaltic 

 motion, urge thcin furtlier ; and if any extraneous fiibftance 

 is detained in the cavity of the inner portion, that part will 

 become a fixed point for the outer, or containing inteftine to 

 act upon. Thus it will be fqueezed on, till at laft the me- 

 fentery, preventing more of the innermoft part from being 

 drawn in, will aft as a kind of flay ; yet, without entirely 

 hindering the inverted outer fold from going ftill further. 

 For fince it is the middle fold which is :.ded upon by the 

 outer, and this aftion continues after the inner portion be- 

 comes fixed, the gut is thrown into folds upon iti'elf ; fo that 

 a foot of inteftine may not form an introfufception more tli;in 

 three inches long. 



The outer portion of inteftine is alone aftive in increafing; 

 the difeafe when once begun'; but if the inner one were 

 capable of equal adion in its natural divedion, the effect 

 would be the fame, w-z^ that of endeavouring to invert itfelf, 

 as, indeed, happens in a prolapfus ani. The outer and inner 

 portions v.ould then tend to draw in more of the gut, v>hile 

 the intermediate part only would, by its aclion, have a eon- ' 

 trary tendency. 



Although capable of producing a prolapfus ani, the ac- 

 tion of the abdominal mufcles cannot aflift, either, in forming 

 or continuing this difeafe, fince the effeft of it muft. be to 

 make equal comprefiion both above and below. 



The manner in which the inteftines are conneded with the 

 m.efentery, would lead one to confider it impoiuble for any 

 portion of the bowels to pafs far v^ithin anotlier, particularly 

 as the incrcafing quantity of mefentery, that is drawn into 

 the introfufcepted part, muft render the further paffage of 

 inteftine more and more difficult. The large inteilines, being 

 alfo more clofely confined in their natural fituations, would 

 fecm to be far lefs liable to the difeafe. One of the largeft 

 introfufceptions ever known, however, was in the colon,, as 

 related by Mr. Whately in the I'hil. Traiif. vol. kxYi. 

 p. 305. The introfufception appeared to have begun at the 

 infertion of the ileum into the colon,, and to have carried in 

 the caecum with its appendix. The ileum pafled on into the 

 colon, till the whole of the afcending colon, the. tranfverfe 

 arch, and defcending colon, were carried into the figmoid. 

 flexure and. rcdum. The valve of the colon being the lead- 

 ing part, it at lail got as low as the anus ; and when the per- 

 fon went to llool, ne only ci!i,-;ried the ileum, for one-half of 

 the large inteftines being filku up by the other, the ileum 

 alone, which pafled through the centre, difcharged its con- 

 tents.. 



