1888.] Beat of the Mammalian Heart. Plasticity of Ice. 331 



III. " On the Electromotive Changes connected with the Beat of 

 the Mammalian Heart, and of the Human Heart in parti- 

 cular." By Augustus D. Waller, M.D. Communicated 

 by Professor Burdon S ANDERSON, F.R.S. Received June 12, 

 1888. 



(Abstract.) 



1. Description of experiments in which the electrical variation con- 

 nected with the spontaneous beat is modified. 



2. The normal ventricular variation is diphasic, and usually in- 

 dicates (1) negativity of apex, (2) negativity of base. 



3. Description of "irregular" variations. 



4. Observations on animals with one or both leading off electrodes 

 applied to "he body at a distance from the heart. 



5. Determination of the electrical variations of the heart on man. 



6. The variation is diphasic, and indicates (1) negativity of apex, 

 (2) negativity of base. 



7. Distribution of cardiac potential in man and animals. " Favour- 

 able " and " unfavourable " combinations. 



8. Demonstration of electrical effects by leading off from the sur- 

 face of the intact body by the various extremities and natural 

 orifices. 



9. Comparison between effects observed on man with the normal 

 and with a transposed situation of the viscera. 



IV. " On the Plasticity* of Glacier and other Ice." By James 

 • C. McConnel, M.A., Fellow of Clare College, Cambridge, 

 and Dudley A. Kidd. Communicated by R. T. Glaze- 

 brook, F.R.S. Received June 11, 1888. 



The experiments described in the following paper were undertaken 

 in continuation of those made by Dr. Main in the winter 1886-87, 

 and described by him in a paperf read before the Royal Society 

 the folio wing summer. The investigation is by no means complete, 

 but the results hitherto obtained seem to us sufficiently novel and 

 important to be worthy of being put on record, while we hope to 



* Dr. Main used the term " viscosity." But this has been always applied in 

 liquids to molecular friction, and we have the authority of Sir Win. Thomson 

 (' Encycl. Britann.,' Art, : Elasticity, p. 7) for reserving it for the same property 

 in solids also, leaving "plasticity" to denote continuous yielding under stress. 



t ' Roy. Soc. Proc.,' vol. 42, p. 329. 



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