No. XVIL] APPENDIX. 265 



I infer that the sensations are simply repeated in the brain, nerve for 

 nerve, action for action, and this first battery I term the sensation or 

 aisthenic battery ; the second pole of this battery is probably connected 

 with the corresponding fibre of the opposite side, by what anatomists call 

 a commissure, and which I have illustrated on the table by a voltaic 

 arrangement. 



We have represented to our minds, not only simple sensations, but 

 also combined impressions : thus, whilst I am looking at all the parts of 

 this theatre, one impression namely, that of a theatre is brought before 

 my mind. There is no difficulty in obtaining this result by voltaic means ; 

 and the mechanism by which I believe it to be accomplished I have termed 

 the syndramic or combination battery. Thus, if we have three primitive 

 nervous fibrils, A,B, C, they may be thus combined, AB, AC, BC, ABC. 

 The diagram behind me illustrates this mode of combination ; and here, 

 upon the table, I have the voltaic arrangement itself, and you cannot fail 

 to observe that these wires, even on this very limited scale, begin to look 

 like the interlacing which we observe in the brain. 



If we divide any space into a certain number of squares, and give to 

 each square a certain name or figure, it will be apparent, that by simply 

 giving the names of the squares filled up with black, the word, or name, or 

 symbol, would at once be accurately described. I have divided this piece 

 of card into certain squares, and if I read you a certain combination of 

 numbers, it would appear, at first, to give no definite idea ; but if you 

 examine carefully, you will find that this combination of numbers brings 

 out the word LIFE. This word, I find, has been very unfortunately chosen, 

 but in reality I only selected the word in illustration of the principle of 

 combination, because it only consisted of four letters, and because each 

 letter was so formed that it very perfectly filled up square spaces. 



Ladies constantly in practice take advantage of this principle in their 

 patterns of worsted work ; and it would be possible so to describe a 

 picture, up to the very limit of our powers of sensation, that it might, 

 from the description alone, be repeated in any country, and yet be a 

 perfect facsimile. 



I dwell thus long upon the syndramic or combination battery, 

 because, in all probability, it constitutes a very large part of the brain. 

 When we consider the large number of ultimate fibres in each organ of 

 sensation, I do not think that we have reason to suppose every possible 

 combination ensues ; and even with regard to ordinary sentient nerves, I 

 think that such a universal combination would be embarrassing to the 

 mind, and that the combination probably would only extend to the nerves 

 of each separate region of the body. It is quite certain that we always 

 know the specific sense by which impressions are learnt that is to say, 

 that we know whether an idea has been derived from the eye, nose, mouth, 

 or other organ of sensation. This resolves itself into one idea for a vast 

 number of sensations, and is a state which can very easily be imitated by 

 voltaic contrivances. I have upon the table a voltaic arrangement of this 

 character, in which but one action is produced from one or all the 

 combinations which exist in the syndramic battery. In some cases, ideas 

 do not arise alone from action on one sense, but on two or more senses at 

 one time a combination which I infer to occur in the syndramic-noemic 

 battery ; and lastly, it is necessary to assume that all these last combina- 



