214 THE MICROSCOPE AND ITS LESSONS. 



of these microscopic cells. We found that three millions 

 of blood-discs would lie in the compass of a pin's head, 

 and these brain-cells are very considerably smaller than 

 they. I cannot tell you the cubical contents of a man's 

 brain, but I can give you its weight, and that is about all 

 that can be told with accuracy and beyond dispute. The 

 weight, then, of an adult male European brain varies 

 between three pounds ten ounces and four pounds six 

 ounces; and the grey matter, of which these infinitely 

 small bodies are composed, is connected (in its entirety) 

 with the mental operations ; and, as Dr. Lawson says, 

 after describing various operations performed upon the 

 brain, " all these facts point to one and the same conclu- 

 sion, viz. that in the cerebrum are located tlie various 

 faculties of mind! 1 But then we come again upon the 

 question, What is memory? Are all these countless, and, 

 except by the aid of the strongest glasses, invisible 

 cerebral cells the storehouses of thought ? and do they 

 constitute what our Shakespeare calls the "mind's eye" ? 

 But, then, think again of the brains some of us have 

 had repeated and rebuilt from new material over and 

 over, perhaps more than ten times. How is it that the 

 mind, which is the source of memory, has not gone with 

 the cerebral cells, the tenant with the dwelling, the seven 

 years' lease having expired ? All that echo replies is, 

 "How?" 



Clearly enough, the multitude of multitudes of 

 cerebral cells in an average-sized human brain are 

 enough, provided only one event in a long life were 

 stored in each, to record the story of its entire length 

 from infancy to old age ; but how the remembrance is 

 retained, year after year, long after these little organisms 

 have passed away, who shall tell ? Surely this is one 

 of the very hardest nuts a materialist has to crack ! 



