134 Researches Regarding Cholera. [part i. 



performed, we might, at all events, assimilate the conditions in the two instances a 

 little more closely to one another. The secretion of fluid might of course have been 

 promoted by the use of drugs or other media introduced into the system, but the 

 complexity of the subject would have been greatly increased by such a mode of 

 procedure, and we therefore decided in the first place to attempt to attain the desired 

 end by means of direct operative interference. It next became necessary to determine 

 in what that interference should consist, and that having been settled, to test with 

 care the ejffects arising from its influence, when employed alone, before proceeding 

 to combine it with any other experiment. 



The best means available and which appeared to warrant a hope of success was 

 section of the intestinal nerves. Moreau's celebrated experiment on section of these 

 nerves showed that the resultant paralysis was accompanied by a copious secretion of 

 watery fluid from the mucous membrane, and it was previously asserted by Pfliiger 

 and Nasse that the splanchnic nerves exerted an inhibitory action on the movements 

 of the small intestine, so that there were fair grounds for the selection of such 

 operations with a view to their combination with the experiments on the injection of 

 organic fluids into the circulation. 



A.— Section of the Splanchnic Nerves. 



Before proceeding to repeat Moreau's experiment, the effects of division of the 

 splanchnic nerves were carefully tested, seeing that it was desirable, if possible, to 

 obtain a means of influencing the whole of the small intestine simultaneously, and not 

 a mere isolated loop or loops as in the procedure adopted by Moreau. The difiiculties 

 of such an operation are considerable, and cannot be overcome without some practice, 

 for the situation of the nerves is such that injury to important vessels and viscera 

 is very easily caused, and the abdominal portion of the nerves in the dog is so short 

 as to render it at first a matter of difficulty to distinguish and isolate such small cords 

 as they are. In our experiments the greater splanchnics alone were divided as the 

 lesser nerves are very difficult to secure, due to their small size and to the fact 

 that there is no such definite guide to their position as in the case of the larger nerves. 

 This guide is afforded by the supra-renal capsule. If the outer edge of this body be 

 carefully cleaned, the greater splanchnic may be found with comparative ease, just 

 as it passes beneath it to enter the semilunar ganglion. The main difficulty in the 

 way is a vein of considerable size, which, near the gland, lies close to and almost 

 parallel with the nerve, and which is very liable to be injured in an operation per- 

 formed in such a narrow space, and affording so many obstructions to the free access 

 of light, as is the angle between the ribs, the diaphragm, and the transverse pro- 

 cesses of the vertebrae. Numerous failures first occurred, but eight operations were 

 successfully performed with the results shown in the following statement: — 



