470 REPORT— 1902. 



Worli of the Mammalian Heart. — Report of the Committee, consisting of 

 Professor J. G. McKendrick (Chairman), Dr. T. G. Brodie 

 (Secretary), and Professor W. H. Thompson, appointed to stiuhj 

 the Power of the Mammalian Heart for performing Worh under 

 varying External Conditions and under the Influence of Drugs. 

 (Brawn up hy the Secretary.) 



A SERIES of experiments have been performed upon the mammalian heart 

 isolated by a special method, in which the work is measured by record- 

 ing the output of the heart when it is made to work against a constant 

 pressure. It was found necessary to determine variations in the working 

 capacity of the heart when the pressure against which it works varies, 

 for this leads to an alteration in the flow through the coronary vessels 

 which in turn leads to changes in the working capacity. The experi- 

 ments of this class are not yet completed. 



The influence of anesthetics upon the isolated heart working against 

 a constant pressure have also been investigated. Chloroform has a most 

 marked depressant action upon the heart. The work performed falls in 

 amount very rapidly, and may altogether cease. Ether has a preliminary 

 stimulant action upon the heart, followed by a depressant eflFect. The 

 depressant eflFect is never so marked as with chloroform, and with 

 ordinary doses is only slight. Suprarenal extract has a most marked 

 stimulant eflfect upon the isolated heart ; it serves as a powerful anti- 

 dote to the depressant action of chloroform. The experiments are still 

 in progress. 



The Micro-Chemistry of Cells. — Report of the Committee, consisting of 

 Professor E, A. SchAfer (Chairman), Professor A. B. Macallum 

 (Secretary), Professor E. Ray Lankester, Professor W. D. 

 H4LLIKURT0N, Mr. G. C. Bourne, and Professor J. J. Mackenzie. 

 (Dravn up hy the Secretary.) 



The Committpe l)eg leave to report as follows : — 



1. The work qf the previous year on the micro-chemical localisation 

 pf the oxidising ferments in the q-lgse was completed, and the results are 

 x\OY ready for publication. 



2. A number of observations were made to determipe if in the 

 pj:otophytan cell the calcium, potassium, sodium, and magnesium are in 

 masked condition. For this purpose the larger- celled species of Spirogyra 

 were enjployed, and the result was that the four elements mentioned were 

 found in the ash from the cytoplasm, nucleus, and chromatophore of these 

 organism?, as veil as in the cell membrane ; but it is only in the latter 

 that they can be demonstrated during the life of the cell. Immediately 

 f)n the occurrence of plasmolysis, or on killing the cytoplasm and nucleus, 

 the potassium and the calcium can be indicated in the plasmolysed 

 spherules and in the dead cytoplasm and nucleus. It is thus shown that 

 during life these elements are combined in some manner which masks 

 their presence. In regard to magnesium and sodium no conclusion could be 

 reached, on account of the fact that for these elements there are no tests 

 f|;S distii^ct op as marked as those which serve for tl^e n^icro-c^pipipa) 



