IOWA ACADEMY OF SCIENCES. 23 



abstruse problems as the specific volume of steam aud its 

 law of tension under varying temperatures. And the 

 improvements in the steam engine, which since the fifties 

 have more than doubled the speed of the piston, while 

 saving at least one fourth of the fuel, have been made 

 under the guidance of Joule and the mechanical theory of 

 heat. In the matter of the advantage of super-heated 

 steam and high pressure, theory still seems to outrun 

 practice. 



In electricity the mere mechanician can take no impor- 

 tant step beyond the scientific discoverer. How happy 

 was the thought which designated the various units of 

 electricity by the illustrous names of the masters of 

 research, — volt, in honor of the professor in the University 

 of Pavia who one hundred years ago gave the world in his 

 crown of cups its first effective reservoir of the new power; 

 ampere, the name of the professor of physics in the College 

 of France, founder of the science of electro dynamics; 

 ohm, in memory of the professor of experimental physics 

 in the University of Munich, discoverer of the law of the 

 strength of the electric current; and farad, in honor of the 

 greatest of them all, Michael Farady, professor of Chem- 

 try in the Institution of England, the prince of experi- 

 menters, whose researches, resulting in the dynamo, con- 

 nected up the industries of the world to the first economical 

 source of electrical energy. 



Illustrations of the dependence of industry on pure 

 science are everywhere at hand. When as an amateur in 

 photography, I take up a package of eikonogen or hydro- 

 quinou, the label with the name of one of the great ani- 

 line factories of Germany, at Elberfield, Mannheim, or 

 Berlin, reminds me of the debt of the Farbenfahriken to 

 men of research. To the chemist is not only due the dis- 

 covery of developers, of such bye products as antipyrine, 

 cocaine, saccharine and vanilline, — it was he who, in the 

 black amorphous coal tar, the former refuse of the gas 

 works, first found there brilliant crystalline dyes which 

 have so largely replaced all other colors in the dye vats of 

 the world. So far as I am aware, no monument has been 



