NATURAL RHYTHM. 149 
tion, which preponderance is not much modified 
by adding the next succeeding proportion, thus, 
tipeas=t$7 Consequently, the organism may fairly 
be supposed to have entered upon the next pro- 
longed period of rest (viz. 185 seconds) with a large 
balance of reserve power; so that when to this large 
balance there was added the further accumulation 
due to the further rest of 185 seconds, we are not 
surprised to find the next succeeding swimming 
bout comprising the enormous number of 894. 
pulsations. But this great expenditure of energy 
seems to have been somewhat in excess of the 
energy previously accumulated by the prolonged 
rest, for this unusual expenditure seems next to 
have entailed an unusually prolonged period of 
exhaustion. At any rate, it is plainly observable 
that the next succeeding proportions are greatly in 
favour of repose; for it is not until 360 seconds 
have elapsed, with only twelve pulsations in the 
interval, that energy enough has been accumulated 
to cause a moderate bout of thirty pulsations. But 
next another long and sustained pause of 240 
seconds supervenes, and, the animal being now fully 
refreshed with a large surplus of accumulated 
energy, the next succeeding swimming bout com- 
prises two hundred pulsations. Lastly, there suc- 
ceeded sixty seconds of rest, and here the observa- 
tion terminated.* 
* If the reader takes the trouble to ascertain the average pro- 
portion between the number of pulsations and the seconds of rest 
in the first observations as far down as the first long pause, viz. 
as above stated, }#9, and if he then balances the succeeding income 
