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Mr. E. Wilson. The Kelvin Quadrant 



time than mammals or frogs, and the difference is so striking that 

 one mast attribute it to the absence of medulla in Teleosts, and must 

 assume that the cortical gland is not absolutely essential to the life of 

 the animal. The longest time that a frog will survive removal of its 

 capsules is, according to Abelous and Langlois,* twelve or thirteen 

 days, and this period is shortened in the summer to forty-eight hours. 

 Mammals usually die in a day or two. 



The validity of these experiments depends obviously upon the 

 fact that all suprarenal material has been actually removed at the 

 operation. This has been verified in two ways. In the first place, 

 previous study of the anatomy of the organs in many individuals has 

 shown that the suprarenals are never more than two in number. 

 Secondly, all three animals have been carefully dissected post 

 mortem, and no trace of suprarenal bodies has been found to be left 

 behind.f 



PettitJ has described a true physiological compensatory hyper- 

 trophy of one suprarenal in the eel after the other one has been 

 removed. This indicates a secreting function for this cortical gland. 

 Pettit looks upon this organ in the eel as the fundamental type of the 

 suprarenal capsule ; but this view is quite untenable in the face of 

 the facts that it has none of the characters of the double suprarenal 

 of mammals, and its removal does not cause death. 



" The Kelvin Quadrant Electrometer as a Wattmeter and 

 Voltmeter." By Ernest Wilson. Communicated by 

 Dr. J. Hopkinson, F.R.S. Received January 11, — Read 

 January 27, 1898. 



During the past seven years the author has had continued experi- 

 ence with the Kelvin quadrant electrometer, both in connection with 

 scientific research and the training of electrical engineering students 

 in the Siemens Laboratory, King's College, London. This paper 

 embodies a good deal of the experience which he has gained with the 

 instrument, and he has been fortunate in that two of these instru- 

 ments were available. The numbers of the instruments are 71 and 

 184. The writer was therefore able to test the one as a Wattmeter, 

 using the other for the purpose of investigating the instantaneous 

 rate at which work was being done by alternate currents. The 

 instrument used as a Wattmeter (No. 184) is of comparatively 



* Loc ext. 



f For the animal which lived 119 days this statement has been verified by Pro- 

 fessor Schafer. 



% ' Eecherches sur les Capsules Surrenales,' These. Paris (Felix Alcan), 1896. 



