SCIENCE IN THE LAST HALF CENTURY. 63 



tion of those who follow science in the hope of finding wealth alongside 

 truth, or even wealth alone. Such a profession is as respectable as any 

 other. And quite as little do I desire to ignore the fact that, if industry 

 owes a heavy debt to science, it has largely repaid the loan by the im- 

 portant aid which it has, in its turn, rendered to the advancement of 

 science. In considering the causes which hindered the progress of 

 physical knowledge in the schools of Athens and of Alexandria, it has 

 often struck me* that where the Greeks did wonders was in just those 

 branches of science, such as geometry, astronomy, and anatomy, which 

 are susceptible of very considerable development without any, or any 

 but the simplest, appliances. It is a curious speculation to think what 

 would have become of modern i)hj'sical science if glass and alcohol had 

 not been easily obtainable ; and if the gradual perfection of mechanical 

 skill for industrial ends had not enabled investigators to obtain, at com- 

 paratively little cost, microscopes, telescopes, and all the exquisitely 

 delicate apparatus for determining weight and measure and for estimat- 

 ing the lapse of time with exactness, which they now command. If 

 science has rendered the colossal development of modern industry pos- 

 sible, beyond a doubt industry has done no less for modern physics and 

 chemistry, and for a great deal of modern biology. And as the captains 

 of industry have at last begun to be aware that the condition of suc- 

 cess in that warfare, under the forms of peace, which is known as in- 

 dustrial competition lies in the discipline of the troops and the use of 

 arms of precision, just as much as it does in the warfare which is called 

 war, their demand for that discipline, which is technical education, is 

 re-acting upon science in a manner which will assuredly stimulate its 

 future growth to an incalculable extent. It has become obvious that 

 the interests of science and of industry are identical; that science can 

 not make a step forward without sooner or later opening up new 

 channels for industry, and on the other hand, that every advance of 

 industry facilitates those experimental investigations upon which the 

 growth of science depends. We may hope that at last the weary mis- 

 understanding between the practical men who professed to despise 

 science, and the high and dry philosophers who professed to despise 

 practical results, is at an end. 



Nevertheless, that which is true of the infancy of physical science in 

 the Greek world, that which is true of its adolescence in the seventeenth 

 and eighteenth centuries, remains true of its riper age in these latter 

 days of the nineteenth century. The great steps in its progress have 

 been made, are made, and will be made, by men who seek knowledge 

 simply because they crave it. They have their weaknesses, their follies. 

 Their vanities, and their rivalries, like the rest of the world; but what- 

 ever by-ends may mar their dignity and impede their usefulness, this 



" There are excelleut remarks to tlie same ert'ect iu Zeller's Philosopbie der Grieelieu, 

 Theil II, Abth. li, p. 407, and in Enckcu's Die Methodcder Aristotelischen, Forscbuug, 

 pp. 138 et seq. 



