138 FRAGMENTS OF SCIENCE. 



the waves of red light are split into exact halves, then, to 

 preserve the light white, the waves of yellow, orange, green, 

 and blue must also be split into exact halves. In short, the 

 reduction must take place, not by absolutely equal quanti- 

 ties, but by equal fractional parts. In white light the pre- 

 ponderance as regards energy of the latter over the smaller 

 waves must always be immense. "Were the case otherwise, 

 the physiological correlative, blue, of the smaller Avaves 

 would have the upper hand in our sensations. 



My wish to render our mental images complete, causes 

 me to dwell briefly upon these known points, and the 

 same wish will cause me to linger a little longer among 

 others. But here I am disturbed by my reflections. When 

 I consider the effect of dinner upon the nervous system, and 

 the relation of that system to the intellectual jDowers I am 

 now invoking — when I remember that the universal expe- 

 rience of mankind has fixed upon certain definite elements 

 of perfection in an after-dinner speech, and when I think 

 how conspicuous by their absence these elements are on the 

 present occasion, the thought is not comforting to a man 

 who wishes to stand well with his fellow-creatures in gen- 

 eral, and with the members of the British Association in 

 particular. My condition might well resemble that of the 

 ether, which is scientifically defined as an assemblage of 

 vibrations. And the worst of it is, that unless you reverse 

 the general verdict regarding the effect of dinner, and prove 

 in your own persons that a uniform experience need not con- 

 tinue uniform — which will be a great point gained for some 

 people — these tremors of mine are likely to become more 

 and more painful. But I call to mind the comforting words 

 of an inspired though uncanonical writer, who admonishes 

 us in the Apocrypha that fear is a bad counsellor. Let me 

 then cast him out, and let me trustfully assume that you 

 will one and all postpone that balmy sleep, of which dinner 

 might under the circumstances be regarded as the indis- 



