EDITOR'S TABLE. 



113 



ably ever remain so. The nature of the 

 union is a mystery, just as the nature 

 of the union between gravity and mat- 

 ter is a mystery ; in both cases we in- 

 vestigate only the laws of the phenom- 

 ena. As the problem is one of the con- 

 nection between two systems of action, 

 the first step toward its solution must 

 be to resolve these two systems into 

 their simplest elements. The structural 

 elements of the nervous system are mar- 

 velously simple ; they consist of micro- 

 scopic cells and fibres, the former being 

 seats or centres of force, and the latter 

 being the means of transmitting it. 



Cells and fibres are the instruments 

 of mental action, and, exactly as we 

 rise in the scale of intelligence in ani- 

 mated creatures, there is an increase 

 in the mass of the nervous centres — 

 that is, a multiplication of the nerves 

 and fibres which constitute them. In 

 man, the most intelligent of the animal 

 series, the organ of intelligence is rela- 

 tively very large, and attains the high- 

 est degree of complexity. 



Prof. Bain represents the nervous 

 elements of the human brain as fol- 

 lows: "The thin cake of gray sub- 

 stance surrounding the hemispheres 

 of the brain, and extended into many 

 doublings by the furrowed or convo- 

 luted structure, is somewhat difficult to 

 measure. It has been estimated at 

 upward of 300 square inches, or as 

 nearly equal to a square surface of 18 

 inches in the side. Its thickness is va- 

 riable, but, on an average, it may be 

 stated at one-tenth of an inch. It 

 is the largest accumulation of gray 

 matter in the body. It is made 

 up of several layers of gray sub- 

 stance divided by layers of white sub- 

 stance. The gray substance is a near- 

 ly compact mass of corpuscles of va- 

 riable size. The large caudate nerve- 

 cells are mingled with very small 

 corpuscles less than the thousandth 

 of an inch in diameter. Allowing for 

 intervals, we may suppose that a linear 

 row of 500 cells occupies an inch, thus 

 VOL. iv. — 8 



giving 250,000 to the square inch for 

 300 inches. If one-half of the thick- 

 ness of the layer is made up of fibres, 

 the corpuscles or cells, taken by them- 

 selves, would be a mass one-twentieth 

 of an inch thick, say 16 cells in the 

 depth. Multiplying these numbers to- 

 gether, we should reach a total of 

 1,200,000,000 cells in the gray covering 

 of the hemispheres. As every cell is 

 united with at least two fibres, often 

 many more, we may multiply this num- 

 ber by four for the number of connect- 

 ing fibres attached to the mass, which 

 gives 4,800,000,000 fibres." 



Now, in saying that such a wonder- 

 ful organism as this is the seat and em- 

 bodiment of the mind, we require to 

 give distinctness to our conceptions, 

 and are compelled to regard the con- 

 nected cells and fibres as the simple in- 

 struments of simple mental processes 

 as the whole fabric is the organ and 

 measure of the whole mind. The cor- 

 poreal elements are cells and fibres — 

 what are the psychical elements in their 

 lowest analysis ? The old division of 

 of the mind into faculties — as reason, 

 judgment, memory, and imagination 

 — is insufficient, for these are far from 

 being ultimate elementary processes, 

 but are rather the most complex actions 

 of the collective forces of the intelli- 

 gence in different modes of exercise. 

 The later psychology resolves all these 

 so-called faculties into a few constitu- 

 ents which form, if we may so speak, 

 the contexture of the intellect. As 

 Prof. Bain remarks : " We have no 

 power of memory in radical separation 

 from the power of reason or the pow- 

 er of imagination. The classification 

 is tainted with the fault called in logic 

 1 cross - division.' The really funda- 

 mental separation of the powers of the 

 intellect is into three facts, called : 1. 

 Discrimination, the sense, feeling, or 

 consciousness, of difference ; 2. Simi- 

 larity, the sense, feeling, or conscious- 

 ness, of agreement ; and, 3. Retentive- 

 ness, or the power of memory or ac- 



