256 SCIEXCE IIS" SHORT CHAPTERS. 



laughed at by Mr. Crookes and everybody else, excepting a few of the 

 utterly crazed disciples of the " Lamb's Conduit Mediums" and the 

 Quarterly reviewer, who actually attempts to explain it by his infalli- 

 ble and ever applicable physiological nostrum of " unconscious 

 cerebration." 



No marvellous story either of ancient or modern date is too strong 

 for this universal solvent, which, according to the reviewer, is the 

 sole and glorious invention of Dr. Carpenter. Space will not now 

 permit me to further describe " unconscious cerebration" and its 

 vast achievements, but I hope to find a corner for it hereafter, 



I may add that the name of the reviewer is kept a profound secret, 

 and yet is perfectly well known, as everybody who reads the article 

 finds it out when he reaches those parts which describe Dr. Carpen- 

 ter's important physiological researches and discoveries. 



CHAPTER XXXIII. 



MATHEMATICAL FICTIONS (BRITISH ASSOCIATION, 1871). 



THE President's inaugural address, which was going through the 

 press in London while being spoken in Edinburgh, has already been 

 subject to an unusual amount of sharp criticism. For my own part 

 I cannot help regarding it as one of the least satisfactory of all the 

 inaugural addresses that have yet been delivered at these annual 

 meetings. They have been of two types, the historical and the con- 

 troversial ; the former prevailing. In the historical addresses the 

 President has usually made a comprehensive and instructive survey 

 of the progress of the whole range of science during the past year, 

 and has dwelt more particularly on some branch which from its own 

 intrinsic merits has claimed special attention, or which his own spe- 

 cial attainments have enabled him to treat with the greatest ability 

 and authority. A few Presidents have, like Dr. Huxley last year, 

 taken up a particular subject only, and have discussed it more thor- 

 oughly than they could have done had they also attempted a general 

 historical survey. 



Every President until 1871 has scrupulously kept in view his judi- 

 cial position, and the fact that he is addressing, not merely a few 

 learned men, but the whole of England, if not the whole civilized 

 world. They have therefore clearly distinguished between the es- 

 tablished and the debatable conclusions of science, between ascer- 

 tained facts and mere hypotheses, have kept this distinction so 

 plainly before their auditors that even the most uninitiated could 

 scarcely confound the one with the other. 



In Sir William Thomson's address this desirable rule is recklessly 

 violated. He tells his unsophisticated audience that Joule was able 

 " to estimate the average velocity of the ultimate molecules or 

 atoms" of gases, and thus determined the atomic velocity of hydro- 

 gen, "at 6225 feet per second at temperature 60 Fahr., and 6055 

 feet at the freezing point ;" that " Clausius took fully into account 

 the impacts of molecules upon one another, and the kinetic energy 



