298 Notices respecting New Books. 



" the Rotation of the Plane of Polarization of a Luminous Ray. Up 

 to the present time the value of this discovery has been principally 

 suggestive ; no new fact has been added to the subject since it left 

 the hands of Faraday. A connexion between light and magnetism 

 is here indicated which none of our theories would have enabled us 

 to predict. None of our hypotheses would have prompted us to 

 seek this result ; they would rather have dissuaded us from the 

 attempt, but this man sees the generally fleeting nature of those 

 images by which the operations of nature are rendered tangible to the 

 human mind, and is not to be warped from his path by a symbol. The 

 method of true scientific investigation is probably incommunicable; 

 it belongs to the individual rather than to the system, and our con- 

 temporaries, we think, miss their mark when they point at Faraday's 

 researches as simply illustrative of the power of inductive philo- 

 sophy. Faraday's researches are illustrative of the power of a strong 

 and independent soul, expressing itself after its own methods, and 

 acknowledging no mediator between it and Nature. You may fill 

 your brain with inductive philosophy, but without the God-given 

 force which this man possesses, and which signalizes him from all 

 others at the present day, you will never accomplish what he has 

 accomplished. Hotly following the discovery of the rotation of the 

 plane of polarization is that of diamagnetism. At the end of the 

 last century Bruggmanns had actually shown that a magnetic needle 

 was repelled by a mass of bismuth : here he stopped. Le BaillifF 

 repeated the experiment with bismuth and antimony : here he 

 stopped. Seebeck and others have touched upon the same subject ; 

 the cherry struck against their lips, but they failed to take it in. 

 These fragmentary glances excited a momentary curiosity and 

 were almost forgotten, until Faraday, without knowing anything 

 of the experiments alluded to, rediscovered the same facts, but 

 instead of stopping, he made them the inlet to a new and vast 

 scientific domain, in which philosophers of all countries now find 

 occupation. The value of Faraday's discoveries consists in a great 

 degree in the amount of intellectual power which they call into 

 action. It has been his good fortune to alight, not upon the iso- 

 lated nuggets of science, which, while enriching himself might have 

 left others without a share, but to strike the golden lodes at which 

 the highest scientific spirits of the present age have worked, and at 

 which thousands yet to come will work with incalculable benefit to 

 mankind. 



The present volume contains numerous oflTshoots from the great 

 discovery just alluded to, — the author's experiments and speculations 

 on Magne-crystallic Action, — the Magnetism of the Atmosphere, 

 and its possible Influence upon the Diurnal Variation of the Mag- 

 netic Needle, — on the Nature of the Lines of Magnetic Force, — on 

 Electric Induction in Subterranean Telegraph Wires, and papers on 

 other kindred subjects. The mention of the telegraiA reminds us 

 of the application of the author's own discovery to telegraphic pur- 

 poses, whereby the grave difficulties presented to the transmission 

 of ordinary voltaic electricity through subterranean wires are prac- 



