250 Electricity and Galvanism. 



an electric machine, the water will merely escape guttatim ; but on 

 setting the machine in action, the particles of water becoming simi- 

 larly electrified repel each other, and the fluid escapes in a continuous 

 stream. In accordance with this fact it was long ago shown, that 

 if a patient have a vein opened in the arm, and the blood happen to 

 escape but sparingly, on placing him on a glass stool and electrifying 

 him, the blood will, like the water in the vessel just alluded to, 

 escape pleno rivo. There has always been a difficulty in explaining 

 the capillary circulation. Many have questioned, and with reason, 

 the possibility of the injecting force of the heart being competent to 

 exert its influence through the minute blood-channels of the body. 

 The electric hypothesis, to which I have just alluded, would certainly 

 to a great extent meet the difficulty, but must at present be admitted 

 with caution in the absence of absolute proof, however much probabi- 

 lities may be in its favour. For it must be recollected that when 

 a body is electrified, its electricity is collected on its surface, and 

 does not extend into its interior ; thus, if a person on a glass stool 

 be connected with the prime conductor of a machine, evidence of 

 electricity can be obtained from every part of his surface ; but none 

 can be obtained from the inside of his mouth for the reason just 

 stated. So the escape of the blood from the vein of an electrified 

 person may indeed be rendered more rapid, without affording the 

 slightest proof that the circulation of the blood in the interior of the 

 body becomes similarly influenced. — London Medical Gazette for 

 May 1847. 



I propose to-day making a few remarks regarding the forms of 

 apparatus employed in the application of electricity and its modifica- 

 tions, to the treatment of disease. Of these, the common electrical 

 machine, and the electro-magnetic apparatus, are the most important : 

 by aid of the former, we obtain small quantities of electricity in a 

 state of high tension, and by the latter we obtain very large quantities 

 of a lower tension, but still far higher than when elicited from the 

 galvanic trough, which, indeed, is now very seldom employed for 

 medical purposes. 



You are all well acquainted with the construction of the common 

 electrical machines ; but a few remarks in connection with their mode 

 of action may not be regarded as altogether useless. 



