5 o THE POPULAR SCIENCE MONTHLY. 



on that occasion by my distinguished predecessor in office, Sir John 

 Lubbock, has proved, at least, that the British Association is not dead 

 in the affections of its members, and it behooves us at this, the first 

 ordinary gathering in the second half-century, to consider what are 

 the strong points to rely upon for the continuance of a career of suc- 

 cess and usefulness. 



If the facilities brought home to our doors of acquiring scientific 

 information have increased, the necessities for scientific inquiry have 

 increased in a greater ratio. The time was when science was culti- 

 vated only by the few, who looked upon its application to the arts 

 and manufactures as almost beneath their consideration ; this they 

 were content to leave in the hands of others, who, with only commer- 

 cial aims in view, did not aspire to further the objects of science for 

 its own sake, but thought only of benefiting by its teachings. Prog- 

 ress could not be rapid under this condition of things, because the man 

 of pure science rarely pursued his inquiry beyond the mere enuncia- 

 tion of a physical or chemical principle, while the simple practitioner 

 was at a loss how to harmonize the new knowledge with the stock of 

 information which formed his mental capital in trade. 



The advancement of the last fifty years has, I venture to submit, 

 rendered theory and practice so interdependent, that an intimate union 

 between them is a matter of absolute necessity for our future progress. ' 

 Take, for instance, the art of dyeing, and we find that the discovery 

 of new coloring matters derived from waste products, such as coal-tar, 

 completely changes its practice, and renders an intimate knowledge of 

 the science of chemistry a matter of absolute necessity to the prac- 

 titioner. In telegraphy and in the new arts of applying electricity to 

 lighting, to the transmission of power, and to metallurgical opera- 

 tions, problems arise at every turn, requiring for their solution not 

 only an intimate acquaintance with, but a positive advance upon, elec- 

 trical science, as established by purely theoretical research in the labo- 

 ratory. In general engineering, the mere practical art of constructing 

 a machine so designed and proportioned as to produce mechanically 

 the desired effect would suffice no longer. Our increased knowledge 

 of the nature of the mutual relations between the different forms of 

 energy makes us see clearly what are the theoretical limits of effect ; 

 these, although beyond our absolute reach, may be looked upon as the 

 asymptotes to be approached indefinitely by the hyperbolic course oft 

 practical progress, of which we should never lose sight. Cases arise, 

 moreover, where the introduction of new materials of construction, or 

 the call for new effects, renders former rules wholly insufficient. In 

 all these cases practical knowledge has to go hand in hand with ad- 

 vanced science in order to accomplish the desired end. 



Far be it from me to think lightly of the ardent students of nature, 

 who, in their devotion to research, do not allow their minds to travel 

 into the regions of utilitarianism and of self-interest. These, the high- 



