314 FRAGMENTS OF SCIENCE. 
point to that wonderful and mysterious medium, which is 
the vehicle of light and radiant heat, as the probable basis 
also of magnetic and electric phenomena. The hope of 
such a connection was first raised by the discovery here 
referred to.* Faraday himself seemed to cling with par- 
ticular affection to this discovery. He felt that there was 
more in it than he was able to unfold. He predicted that 
it would grow in meaning with the growth of science. 
This it has done; this it is doing now. Its right inter- 
pretation will probably mark an epoch in scientific history. 
Rapidly following it is the discovery of Diamagnetism, 
or the repulsion of matter by a magnet. Brugmans had 
shown that bismuth repelled a magnetic needle. Here he 
stopped. Le Bailliff proved that antimony did the same. 
Here he stopped. Seebeck, Becquerel, and others, also 
touched the discovery. These fragmentary gleams excited 
a momentary curiosity and were almost forgotten, when 
Faraday independently alighted on the same facts: and, 
instead of stopping, made them the inlets to a new and 
vast region of research. The value of a discovery is to be 
measured by the intellectual action it calls forth; and it 
was Faraday's good fortune to strike such lodes of scientific 
truth as give occupation to some of the best intellects of 
our age. 
The salient quality of Faraday's scientific character 
reveals itself from beginning to end of these volumes; a 
union of ardor and patience the one prompting the attack, 
the other holding him on to it, till defeat was final or vic- 
tory assured. Certainty in one sense or the other was 
necessary to his peace of mind. The right method of in- 
vestigation is perhaps incommunicable; it depends on the 
individual rather than on the system, and the mark is 
missed when Faraday's researches are pointed to as merely 
* A letter addressed to me by Professor Weber oil March 18th last 
contains the following reference to the connection here mentioned: 
" Die Hoffnung einer solchen Combination ist durch Faraday's 
Entdeckung der Drehiing der Polarisationsebene durch magnetische 
Directionskraft zuerst, und sodann durch die Uebereinstimmung der- 
jenigen Geschwindigkeit, welche das Verhaltniss der electro- 
dynamischen Einheit -zur electro-statischen ausdriickt, mit der 
Geschwindigkeit des Lichts angeregt worden; und mir scheint von 
alien Versuchen, welche zur Verwirklichung dieser Hoffnung ge- 
macht worden sind, das von Herrn Maxwell getuachte am erfol- 
greichsteu." 
