28o ROUGH WAYS MADE SMOOTH. 



in. her lover's affections which had taken place in her state 

 of second consciousness ; and a painful explanation was 

 necessary. This, however, she bore very well ; and she 

 has since recovered her previous bodily and mental health. 

 There is little in this interesting narrative to suggest that 

 the duality of consciousness in this case was in any way 

 dependent on the duality of the brain. During the patient's 

 abnormal condition, the functions of the brain [proper] 

 would seem to have been for a time in complete abeyance, 

 and then to have been gradually restored. One can perceive 

 no reason for supposing that the shock she had sustained 

 would affect one side rather than the other side of the brain, 

 nor why her recovery should restore one side to activity and 

 cause the side which (on the dual brain hypothesis) had 

 been active during her second condition to resume its 

 original activity. The phenomena appear to suggest that in 

 some way the molecular arrangement of the brain matter 

 became modified during her second condition ; and that 

 when the original arrangement was restored all recognisable 

 traces of impressions received while the abnormal arrange- 

 ment lasted were obliterated. As Mr. Slack presents one 

 form of this idea, * the grey matter of the brain may have its 

 molecules arranged in patterns somewhat analogous to those 

 of steel filings under the influence of a magnet, but in some 

 way the direction of the forces or vibrations may be 

 changed in them. The pattern will then be different.' We 

 know certainly that thought and sensation depend on 

 material processes, chemical reactions between the blood 

 and the muscular tissues. Without the free circulation of 

 blood in the brain, there can be neither clear thought nor 

 ready sensation. With changes in the nature of the circula- 

 tion come changes in the quality of thought and the nature 

 of sensation, and with them the emotions are changed also. 

 Such changes affect all of us to some degree. It may well 

 be that such cases as we have been dealing with are simply 

 instances of the exaggerated operation of causes with which 

 we are all familiar ; and it may also be that in the exaggera- 



