182 FKAGMENTS OF SCIENCE. 



This was the work of the physicist: then came the 

 conquests of the comparative anatomist and physiolo- 

 gist, revealing the structure of every animal, and the 

 function of every organ in the whole biological series, 

 from the lowest zoophyte up to man. The nervous sys- 

 tem had been made the object of profound and con- 

 tinued study, the wonderful and, at bottom, entirely 

 mysterious controlling power which it exercises over 

 the whole organism, physical and mental, being recog- 

 nised more and more. Thought could not be kept back 

 from a subject so profoundly suggestive. Besides the 

 physical life dealt with by Mr. Darwin, there is a psychi- 

 cal life presenting similar gradations, and asking 

 equally for a solution. How are the different grades 

 and orders of Mind to be accounted for? What is the 

 principle of growth of that mysterious power which on 

 our planet culminates in Eeason? These are questions 

 which, though not thrusting themselves so forcibly 

 upon the attention of the general public, had not only 

 occupied many reflecting minds, but had been formerly 

 broached by one of them before the 'Origin of Species' 

 appeared. 



With the mass of materials furnished by the phy- 

 sicist and the physiologist in his hands, Mr. Herbert 

 Spencer, twenty years ago, sought to graft upon this 

 basis a system of psychology; and two years ago a 

 second and greatly amplified edition of his work ap- 

 peared. Those who have occupied themselves with the 

 beautiful experiments of Plateau will remember that 

 when two spherules of olive-oil suspended in a mixture 

 of alcohol and water of the same density as the oil, 

 are brought together, they do not immediately unite. 

 Something like a pellicle appears to be formed around 

 the drops, the rupture of which is immediately followed 

 by the coalescence of the globules into one. There are 



