204 SKETCH OF THE LIFE AND ACHIEVEMENTS 



investigation of a phenomenon apparently iso- 

 lated, conceals not unfrequently the germ of a 

 great discovery. When Galvani irritated the 

 sensitive fibres of the nerves by the touch of 

 heterogeneous metals, his next contemporaries 

 did not expect that the contact-electricity of 

 the Voltaic pillar would reveal in the alkalies 

 silver-bright metals, swimming upon the surface 

 of water, and of an inflammatory nature ; that 

 the pillar itself would become the most important 

 instrument in analytic chemistry a thermoscope 

 and a magnet. When Huyghens commenced 

 to solve the phenomena of light of the calc-spar, 

 no one could foresee that the brilliant achieve- 

 ments of a philosopher of our own days 

 Arago's, 1811 colored polarization phenomena 

 would enable us, with the assistance of a small 

 fragment of a mineral, to discover if the light of 

 the sun proceeds out of a solid mass, or out of a 

 gaslike envelope ; if comets reflect their own or 

 borrowed light. A thorough appreciation of 

 all branches of science is of great importance in 

 our own time ; inasmuch as the material wealth 

 and the growing prosperity of nations is based 

 upon the careful use of their natural produc- 

 tions.* Themost superficial glance at the present 



* " Civilization" says Baron Liebig, " is the economy oj 

 power, and English power is coal" See also Sir William 



