GASEOUS ACCUMULATIONS. 131 



the upward pressure of the diaphragm), but also on the transmis- 

 sion of certain gases into the blood. In these cases we should not 

 so much suspect the resorption of carbonic acid as of hydrogen 

 and its compounds. The amylacea, in undergoing butyric fermen- 

 tation, which is only impeded in the intestine by the free acid 

 of the gastric juice, yield hydrogen, which in its nascent state 

 unites with the sulphur of the decomposed protein-bodies, and 

 thus produces the sulphuretted hydrogen, which exerts so injurious 

 an effect on the blood. The presence of sulphuretted hydrogen in 

 the gaseous contents of the small intestine may, moreover, be 

 readily perceived from the eructations which are developed in from 

 four to eight hours after a meal. It is further worthy of notice, 

 that these eructations of sulphuretted hydrogen are very common 

 after the use of ferruginous preparations ; it is possible that the 

 presence of iron facilitates the conversion of the alkaline sulphates 

 into metallic sulphides, and occasions the formation of sulphide 

 of iron, whose decomposition by acids gives rise to the produc- 

 tion of sulphuretted hydrogen. The formation of sulphuretted 

 hydrogen after the use of the preparations of sulphur, is so well 

 known an occurrence as hardly to require notice, and demands no 

 explanation. 



Gaseous accumulations are much more frequent in the large 

 intestine, where they are often very considerable, than in the sto- 

 mach and small intestine. According to Magendie and ChevreuPs 

 investigations, the oxygen has here altogether disappeared ; they 

 found from 43'5 to 70-- of carbonic acid, from 18'40 to 51 '03^ of 

 nitrogen, and from 5 '4 7 to 1 1'6-g- of carburetted hydrogen: Chevillot* 

 found in the gas contained in the large intestines of aged persons, 

 from 23-11 to 93-00 g- of carbonic acid, from 2 to 3 of oxygen, from 

 95*2 to 90'Of of nitrogen, and 2S'0% of carburetted hydrogen. In two 

 analyses of the flatus, Marchand found 36*5 and 44'5-g- of carbonic 

 acid, 29-0 and 14'0 of nitrogen, 13'5 and 15*8 of hydrogen, 22'0 

 and 15'5-g- of carburetted hydrogen, and in the latter of the cases 

 1'0-g- of sulphuretted hydrogen. It is worthy of remark that the 



* [On referring to the Journ. de Chim. meM., we find that the largest 

 quantity of carbonic acid discovered in the digestive canal generally was from 

 92 to 93g, and that the mean quantity in the large intestines was 23'llg. The 

 quantity of oxygen is not stated : Ckevillot only observes that he found it in the 

 large intestine five times in fifty-four cases. The mean quantity of nitrogen in 

 the large intestines of twenty-seven aged persons was 73 ; the maximum is not 

 given in the memoir. In ninety-six cases, ten only afforded carburetted hydrogen ; 

 one in the small intestine, and nine in the large intestine. The greatest quantity 

 found was 18*8g. G. E. D.]] 



K 2 



