198 THE POPULAR SCIENCE MONTHLY. 



passed upon his performance the sweeping criticism that he had missed 

 the grandest opportunity ever offered to man for saying something or 

 holding his tongue. And, whenever this Association, comprising not 

 only those who teach, but many who create science, assembles, as it 

 now does, to listen to the address of its retiring president, if he is duly 

 sensible of his responsibility, he would gladly avail himself of Mira- 

 beau's alternative, either of being equal to the occasion or of being- 

 silent. But the rule of the Association, adopted in the original draft 

 of the constitution at Philadelphia, and the example of my predeces- 

 sors which I am unwilling to reverse, leave me no choice ; and when 

 I see around me, not the terrible monsters of the French Revolution, 

 maddened by the miseries of a down-trodden country, but calm and 

 high-minded lovers of truth, I feel sure of a just and generous criti- 

 cism. Welcome, then, the precious opportunity, enjoyed by the presi- 

 dent of this Association, of discussing some of the great themes of sci- 

 ence before an audience which has for its nucleus the original investi- 

 gators, discoverers, and inventors in the country, and which, like the 

 sun, is surrounded by an extensive chromosphere only a little less brill- 

 iant than the central body by contrast ; and let my earnest endeavor 

 be not to abuse or waste the great privilege. 



I am confronted on the very threshold of my address by the doubt 

 whether it were better to beat out the little bit of golden thought, for 

 which I have time and capacity, into a thin leaf which shall merely 

 gild the whole vast surface of scientific investigation, even for a single 

 year, or to condense it into a solid though minute globule, only big 

 enough and bright enough to light up some narrow specialty. The 

 general practice which prevails, of selecting a president alternately 

 from the two principal sections into which the Association is divided, 

 will justify me in paying my particular addresses to the physical sci- 

 ences, knowing that the large and active depai - tment of Natural His- 

 tory will be properly treated in its turn by those most competent to 

 do it. Not even the capacious mind of a Goethe, a Humboldt, a Whe- 

 well, or a Herbert Spencer, is large enough to give a decent shelter to 

 all the subjects which come within the scope of this Association. At 

 the same time I must say that I sympathize with the remarks made by 

 President Hunt at Indianapolis, when he questioned the propriety of 

 excluding geology from the ranks of the physical sciences ; only I 

 would give them a still wider significance. Physical science is dis- 

 tinguished from natural history not so much by its subjects as its 

 methods. In my imagination, I can picture to myself all these sub- 

 jects as being handled in the same masterly grasp of mechanics and 

 mathematics by which the physical astronomer holds in his hands the 

 history and the destiny of the solar system. "What is only a dream or 

 a fancy now may become a reality to the science of the future. Why, 

 asked Cuvier, may not natural history some day have its Newton, to 

 whom the laws of circulation of the sap and the blood will be only as 



