596 Mr. Charles Merrier [May 3, 



WEEKLY EVENING MEETING, 

 Friday, May 3, 1901. 



Sir James Crichton-Browne, M.D. LL.D. F.E.S., Treasurer and 

 Vice-President, in the Chair. 



Charles Meroier, Esq., M.B. F.B.C.S. M.B.C.P. 



Memory. 



The programme of my discourse to-night is a very modest one. I 

 have no ingenious invention to describe ; no startling discovery to 

 announce ; I can recommend no specific by which you may attain to 

 the powers of memory of a Porson or a Macaulay ; but, in thinking 

 over the subject, it has seemed to me that under the term memory 

 several things that are quite distinct have been included, and the task 

 that I have set myself is to discriminate between these different 

 meanings, to display some of their bearings on one another, and to 

 bring this mysterious faculty into line with experiences which seem 

 to us simpler and more intelligible. 



In the first place, there is the very obvious distinction between 

 memory and memories — between the process of remembering and the 

 results of the process ; the same distinction that we draw between 

 the process of thinking and the thoughts that result, or between the 

 process of building and the houses that result. I propose to deal 

 first with the result, and then with the process. 



The iron wire that you see here is clamped securely at the top, 

 and at the lower end is attached to what is known as a twisting 

 couple. It is so arranged that when a weight is hung on this cord 

 the wire is twisted to the right, and when the weight is hung on this 

 other cord, the wire is twisted to the left. When the weight is re- 

 moved, the wire at once springs back to its original position. In this 

 case the amount of distortion was within the limit of elasticity of the 

 wire. Now I double the weight, and twist the wire further round, 

 and now, when the weight is removed, the pointer shows that the 

 wire does not return to its original position. It has been twisted 

 beyond the limit of its elasticity, and has acquired what is called a 

 " permanent set." We may look upon this permanent alteration in the 

 shape of the wire as a memory, a structural memory, of the experience 

 that it has undergone. At this position the wire will remain for ever 

 unless it is subjected to some new experience. The memory that it 

 has acquired is a permanent memory. 



Now let us take this new position of the wire as our point of 



