PROCEEDINGS OF THE SOCIETV. 123 



Shilliiigfcon Scales worked to the hospital a mile away, so that all 

 abnormal hearts belonging to patients in the wards of the hospital could 

 be recorded without the patients leaving their beds or being incon- 

 venienced in any way. Somewhat elaborate procedures were, however, 

 necessary in order to standardize so extraordinarily sensitive an instru- 

 ment, to compensate for the resistance of the human body, and to 

 compensate also for the additional displacement of the wire due to what 

 was known as "skin-current." The process, it would be seen, was 

 truly a photo-micrographic process — the recording on a photographic 

 plate by means of a Microscope of minute variations in potential. The 

 heart-beat came out as a beautiful, elaborate, and instructive tracing, 

 each one almost peculiar to its owner ; a movement of a finger would 

 become quite a coarse tracing. Tracings of many hearts were then 

 shown as lantern pictures, representing many organic lesions, and also 

 tracings showing the effects of various drugs upon the hearts of the 

 frog, the cat, and the rabbit, and their alteration in the heart-beat, more 

 especially rauscarin, adrenalin, pilocarpin, atropiu, chloral hydrate, squill, 

 and chloroform. 



Mr. Barnard said that there had been one point in Mr. Shillington 

 Scales' extremely lucid lecture upon which he was not quite clear. Mr. 

 Scales had commenced by speaking about difference of potential, but 

 then went on to speak of measuring his current in parts of an ampere, 

 and referred several times to " current " in the course of his lecture. 

 Was it not an electrical difference of potential that set up the effects 

 described ? Some interesting work had been done some few years ago 

 by Chunder Bose, of Calcutta, and by Burdon Sanderson, who had 

 obtained results somewhat similar to those they had seen that evening. 

 In these cases the alteration in differences of potential had always been 

 the cause of the results observed. 



Mr, Shillington Scales said that the use of the word " current " was 

 somewhat misleading. The tracings shown were really a matter of 

 difference of potential, rather than of actual current. He had said, it 

 would be remembered, that the apparatus was adjusted so that there 

 was a movement of 1 cm. per millivolt. 



Mr. Barnard understood that the galvanometer was set to measure in 

 millivolts ? 



Mr. Shillington Scales answered that it was set to measure one 

 millivolt per cm. ; the waves they had seen had been those of difference 

 of potential on this scale. The actual current passed could be inde- 

 pendently arrived at. 



In reference to what had been said about Dr. Bose, of Calcutta, a 

 few years back Dr. Waller had done some interesting work on p'ant- 

 leaves from his garden. The leaves were placed in a box where light 

 could play upon them, and distinct changes in potential were observed 

 when under the influence of the sun's rays or of the arc light. Dr. 

 Waller said, however, that the most interesting part was that when the 

 plant had started flowering, the leaf did not show these differences in 

 potential to any such extent. 



The President said he would like to congratulate Mr. Shillington 

 Scales on his extremely interesting lecture on a somewhat different sub- 



