REPRODUCTION 99 



of theory as to their meaning. Into these 

 points it is not possible here to enter, but what 

 one has to consider is the nature of the process 

 which has just been described. 



Is At chemico-physical in its characterjDr_js Vital or 

 it a purely vital phenomenon ? A good deal mechan i- 

 of attention has been directed to this inquiry, 

 and particularly by Professor Hartog,* who 

 points out that the spindle and the external 

 radiations described above make up a " strain- 

 figure," like that of the " lines of force " in 

 relation to the poles of a magnet. " Such," 

 he continues, " we can demonstrate in a plane 

 by spreading or shaking iron filings on a piece 

 of paper above the poles of a magnet, or in Mitokinct- 

 space by suspending finely divided iron in a lsm 

 thick liquid, such as mucilage or glycerine and 

 bringing the vessel with the mixture into a 

 strong magnetic field ; the latter mode has the 

 advantage of enabling us to watch the changes 

 in the distribution of the lines under changing 

 conditions or continued strain." From this we 

 gather that there are at the very least strong 

 features of resemblance between the remark- 

 able dance of Tlie chroniOMuines and operations 

 which can be produced by means of purely 

 physical conditions, but does this mean that 



* Op. cit., p. 26, for references, etc., see his paper, Proc. 

 Roy. Soc., 1905, B. Ixxvi., p. 548. 



