Scientific Lectures. 185 



ping needle carried over its surface. I have evolved a current of elec- 

 tricity from a magnet by cutting with a closed conductor across those 

 lines in which a magnetic needle freely suspended places its length. 

 I did the same with the earth by cutting across those lines which are 

 marked out by the pointing of the dipping needle. Therefore, what 

 am I authorized to infer ? When the effects are the same, the causes 

 must be the same ; for, according to all the principles of philosophy, 

 and conformable to that universal experience which we call common 

 sense, like causes produce like effects. 



Have I not shown you that the earth is indeed a great magnet ? 

 But I hope I have shown you more, much more than this ; for I trust 

 I have given you an insight into those methods by which men of 

 science work out great truths. Truth, of all value in itself, simply 

 because it is truth, irrespective of any practical application it may 

 contain. Yet the process by which we have been led to such grand 

 results teaches even more than I can express ; and I retire behind the 

 true eloquence of the great master of experiment, and leave you with 

 these words of the good Faraday : " We learn by such results as these 

 what is the kind of education that science offers to man. It teaches 

 us to be neglectful of nothing; not to despise the small beginnings; 

 they precede, of necessity, all great things. Vesicles make clouds ; 

 they are trifles, light as air, but then they make drops, and drops 

 make showers, rain makes torrents and rivers, and these can alter the 

 face of a country, and even keep the ocean to its proper fullness and 

 use. It teaches a continued comparison of the small and great under 

 differences almost approaching the infinite, for the small as often con- 

 tains the great in principle, as the great does the small ; and thus the 

 mind becomes comprehensive. It ' teaches to deduce principles care- 

 fully, to hold them firmly, or to suspend the judgment, to discover 

 and obey law, and by it be bold in applying to the greatest what we 

 know of the smallest. It teaches us first, by tutors and books, to 

 learn that which is already known to others, and then, by the light 

 and methods which belong to science, to learn for ourselves and for 

 others ; so making a fruitful return to man in the future for that 

 which we have obtained from the men of the past. Bacon, in his 

 instruction, tells us that the scientific student ought not to be as the 

 ant, who gathers merely, nor as the spider, who spins from her own 

 bowels, but rather as the bee, who both gathers and produces.''* 



* The Life and Letters of Faraday. By Dr. Perce Jones. London, 1ST0, vol. ii, pp. 103, 404. 



