236 STUDIES IN LIFE AND SENSE. 



matter of the brain, a layer which we have already seen to constitute 

 the most important part of the brain-substance. This grey matter is 

 seen to exist in tolerable uniformity over large tracts of brain-substance, 

 and it is invariably in the hinder region of the brain that it attains its 

 greatest complexity and development. The form of the skull is 

 dependent on the amount and disposition of the white matter, and 

 not on that of the grey ; and the former, as we have seen, has but a 

 minor influence or part in the mental constitution, since its function 

 is merely that of conducting, and not of originating thoughts and 

 impressions. Since, then, phrenology lays so much stress on skull- 

 conformation as a clue to brain-structure, it must be regarded as 

 dealing rather with the results of the disposition of the white 

 matter than with that of the grey and this latter assumption of 

 necessity involves a second, namely, that phrenology has no status as 

 a science of mind at all. 



There is one consideration concerning the practical application 

 of the phrenologist's assertions too important to be overlooked, 

 namely, the difficulty of detecting or of mapping out on the living 

 head the various " bumps " or organs of mind which appear to be so 

 lucidly localised on the bust or chart. The observer, who might 

 naturally think the determination of the " bumps " an easy matter, 

 has but to try to reconcile with a phrenological chart or with the 

 brain-surface itself (fig. 23), the configuration of a friend's cranium, 

 and he will then discover the impossibility of distinguishing where 

 one faculty or organ ends and where another begins. How, for 

 instance, can the exact limits of the four or five organs of mind, to be 

 hereafter alluded to more specifically, which are supposed to exist in 

 the line of the eyebrow, be determined ? What is the criterion of 

 excessive or inferior development here, and how may we know when 

 one " encroaches " upon another to the exclusion, or atrophy of the 

 latter ? The practical and exact application of phrenology indeed 

 constitutes one of its gravest difficulties. Added to the difficulty or 

 impossibility of accurately mapping out the boundaries of the phre- 

 nologist's organs, we must take into account the fact that we are 

 expected to detail these organs through, in any case, a considerable 

 thickness of scalp, which veils and occludes, as every anatomist knows, 

 the intimate conformation of the skull-cap. At the most, the phreno- 

 logist may distinguish regions ; his exact examination of the living 

 head a la the phrenological chart or bust, is an anatomical impossi- 

 bility. 



But the anatomist has also something of importance to say regard- 

 ing the actual existence of certain of the " organs " of mind mapped 

 out by the phrenologist Leaning trustfully upon their empirical 

 deductions, the phrenologists have frequently localised faculties and 

 organs of mind upon mere bony surfaces separated from the brain by 



