ACTION OF ALCOHOL UPON CIRCULATION— WOOD AND IIOYT. 



59 



Experiment -2'2. 



Looking over the records of these experiments will show that in Experiment 19 the exhi- 

 bition of one-fourth of 1 per cent of alcohol was followed by a distinct fall of the heart work; 

 that in Experiment 20 the use of 1 per cent of alcohol was followed I >y a temporary rise, soon 

 giving way to a distinct fall, which became more accentuated when 3 per cent of alcohol was 

 Used; that in Experiment 21 one-fourth of 1 per cent of alcohol apparently produced a very 

 decided and persistent rise of heart work, which lasted until the alcohol was increased to 1 per 

 cent, when there was a pronounced fall, not, however, below the norm; whilst later 5 per cent 

 of alcohol rapidly decreased the heart work to below the norm; that in Experiment 22 the heart 

 work was distinctly and persistently increased by the exhibition of one-fourth of 1 per cent 

 of alcohol, the increase being maintained for over half an hour, until the exhibition of three- 

 fourths of 1 per cent of alcohol produced a fall below the norm. 



On the whole these experiments seem to us to indicate that in small doses alcohol increases 

 the work of the isolated frog's heart, but the results obtained were distinctly discordant and 

 unsatisfactory. In all these experiments the hearts of small frogs were used, and after much 

 experience witli Kroneker's apparatus, Williams's apparatus, and the one shortly to be described, 

 it is clear to us that experimental results reached by the use of small hearts are not reliable. 

 The resistance in either the Kroneker or the Williams apparatus, when the small heart is used, 

 is out of all proportion to the cardiac power, and feeble muscle fiber may well stretch, give way, 

 or lose functional ability rapidly under the strain. Moreover, in the Williams apparatus, when 

 the heart is small it is difficult to avoid injury to it in the insertion and securing of the canula in 

 the truncus arteriosus, and we know of no way of judging with certainty whether the heart has or 

 has not been injured. Whatever the reasons may be, of this fact we are confident, namely, that 

 even with the best forms of "frog's heart apparatus,'" if the experimental results are to be per- 

 sistent in the one experiment and consistent in the various experiments, it is essential that the 

 hearts of very large bullfrogs or of large snakes or tortoises be employed. We believe that the 

 failure to obtain a rise in Experiment 19 from the one-fourth per cent of alcohol was probably 

 due to injury of the heart in the making of the preparation. 



Led by what we consider to be the difficulties inherent to the older forms of apparatus, we 

 have devised and used one which is shown in tig. 3, an apparatus which is of course a modifica- 

 tion of the Williams apparatus. This apparatus consists, beginning at the left, in a pair of 

 Mariott bottles, united by a Y-shaped tube with a clip so arranged as to shut off either bottle at 

 will. Then, of the ordinary Williams apparatus, with this modification, that at the distal end 

 the blood is allowed to pass through a glass tube and to drop into a beaker glass for a fixed 



