44 FUNCTIONAL INERTIA 



have seen, one of the results of the possession of 

 functional inertia. 



Or again, take the case of the rectum accustomed 

 to be emptied every day at a particular hour : in 

 many cases it will take on this diurnal periodicity 

 and endeavour to establish its peristalsis regularly 

 at the same hour every day the " habit " learned 

 through affectability is perpetrated through func- 

 tional inertia. 



Paget * has some very pregnant remarks on time- 

 rates and organic periodicities. " The organic pro- 

 cesses of repair in each tissue are adjusted to a 

 certain time-rate which is variable according to 

 [affectability] but is not determined by external 

 conditions " [functional inertia]. The time-rate is 

 implanted by the implanted properties, affectability 

 and the inertias, and for each unit of nutrition 

 might be reckoned a unit of time. The periodicities 

 of organic life appear to be prominent instances of 

 this law . . . the rhythmic movements of the heart 

 or the motions of cilia." " In the recognition of 

 the chronometry of organic processes, there is un- 

 questionably great promise for the future ; for it is 

 plain that the observance of time in the motions of 

 organic molecules is as certain and universal, if not 

 as exact, as that in the motions of heavenly bodies. 

 Each organic process has a definite time-rate ; and 

 each cell has its appointed period of life different 

 for different kinds of cells.". . . " Each cell has its 



* Paget, " The Chronometry of Life," Proc. Royal Institution, 

 vol. iii. 1858-1860, pp. 117-124. 



