220 



Rev. S. Haughton. On some [Mar. 11, 



where ?i=nnmber of lifts, 



/=time of each lift, 



fi 1 coefficients to be found from 

 AJ the experiments themselves. 



From this equation, and from the experiments themselves, it ap- 

 peared that there was a particular time of lift — 



t=T, 



at which the maximum work was done, and that, 



,=-L ........ ... (2). 



The object of the series of experiments carried on during six months 

 of the winter of 1876-7, and described in the present note, was to 

 find in what manner the co-efficients t, or /3, vary with the weight 

 employed and lifted. The experiments were conducted in every 

 respect as those described in Note VII, the conditions of which I here 

 quote and repeat : — 



" The following experiments were made during the last six months 

 upon Dr. Macalister : — 



" A pair of dumbbells, held one in each hand, were raised simul- 

 taneously, from the vertical to the horizontal position, and again 

 lowered, at a rate regulated by a metronome made for the purpose. 

 No rest was allowed at the beginning or end of the motion, which 

 took place as before, under the following conditions, viz. : — 



" 1. To keep time with the metronome. 



" 2. To raise the weights in the transverse plane. 



" 3. To supinate the hands. 



" 4. To abstain from all bending of the knees or spinal column. 

 " 5. The experimenter not to count the lifts. 



" The experiments were made at intervals of never less than 

 24 hours, so as to avoid all risk of the muscles becoming trained ; 

 and on each occasion the weights were lifted until it became impossible 

 to effect another lift, without violating condition No. 4, indicating that 

 other muscles were called in to aid the shoulder muscles already worn 

 out." 



I have embodied in this note, the experiments made upon Dr. Mac- 

 alister in 1875-6, Note VIII, " Proc. Roy. Soc," vol. xxv, p. 132. 



