ELECTRO-PHYSIOLOGY. 317 



I shall pay a word, finally, of tlic action of tlie current on tlic ganglionic 

 nerve:?. Humboldt first studied the action of the current on the cardiac plexus 

 and on the ganglionic system of the lower belly. In the former case he ob- 

 Berved, and it was afterwards verified by others, that on keeping the circuit 

 closed for a certain time the pulsations of the heart show no difference, but that 

 if the electric excitation be continued these pulsations become more frequent, 

 and that this fn^quency lasts for a certain time after the current has ceased to 

 pass. When the ganglionic system of the lower belly is operated upon with 

 the current, an analogous fact is noticed. The vermicular motion of the intes- 

 tines is by degrees accelerated, and this acceleration also continues for a certain 

 time after the opening of the circuit. In these two effects the electric excita- 

 tion of the ganglionic nervous system would seem to differ from that of the 

 mixed nerves in being, as regards the former, continuous during the passage of 

 the current, slower in manifesting- itself and slower in ceasing. 



This subject, as well in its therapeutic applications as its physiology, calls 

 for renewed investigation and more thorough research, especially as regards 

 man himself; and its prosecution should be directed, among other things, to 

 determining with exactness the quantity of urea in the urine, the quantity of 

 carbonic acid exhaled, the varied composition of the bile and of the products 

 of digestion, according as man or the animal experimented upon has under- 

 gone for a longer or shorter time the action of the current, both interrupted and 

 continuous. 



This study would be of so much the more interest as we now know that the 

 ganglionic system acts on the sanguineous vessels at one time by constricting, 

 at another by dilating them. This has been verified in the valuable experi- 

 ments of Budge and lieruard. After having divided, in a living animal, a cer- 

 tain nervous fibre which receives at least in part its action from the ganglionic 

 system, through which division the ear of the corresponding part becomes much 

 warmer than the other and is engorged with blood, the physiologists just named 

 found that, by exciting with the current the peripherous portion of the same 

 fibre, the circulation of the blood was restored and the elevation of temperature, 

 which was but a secondary effect, disappeared. It is probable that in the func- 

 tions of secretion and in the physio-chemical action of nutrition analogous 

 effects would present themselves. 



I cannot conclude this lecture, which completes the study of the physiologi- 

 cal phenomena excited by electricity, being the first part of this course, without a 

 glance at the therapeutic uses of electricity. Aftfcr the discovery of the Leyden 

 jar, and even later, after that of the voltaic pile, the new and singular eff'ects of 

 electricity had.so exalted the imagination of the students of therapeutics that 

 the mysterious agent of life, the universal medicine, was supposed to have been 

 found. These fantastic expectations were of course soon dissipated, and there 

 remained, as there will continue to remain, in the science only the results of 

 observations well and diligently made and specifically founded on electro- 

 physiological researches. 



As it had been observed that albumen coagulated around the positive elec- 

 trode, and this through the acid developed by electrization and which coagu- 

 lates the albumen as any free acid would do, it was inferred that the electric 

 current might dispel the cataract, if in the no longer transparent crystalline an 

 alkali were generated with the negative electrode. In making the experiment 

 of the electrization of albumen, the coagulum is seen to be formed around the 

 two electrodes, although, as might be expected, in a greater degree around the 

 positive than the negative one, but it is never found that, by inverting the cur- 

 rent, the albumen which has coagulated around the positive electrode is dis- 

 persed, because this electrode has become negative. Hence it is that with the 

 electric current not only can the cataract not be cured, but, on the other hand, 

 it may with great certainty be created. 



