EULOGY ON ARTHUR AUGUSTE DE LA RIVE. 195 



coveries. They were all three very religious, aud delighted in meditat- 

 ing upon subjects of a metaphysical character. The first sought to 

 explain universal attraction by magnetism ; the second denied even the 

 existence of matter, and considered each atom as a center of force 

 whose vibrations are felt throughout the universe ; they endeavored to 

 defend, against the encroachments of the partisans of physical forces 

 the domain of the spirit, that something which thinks, affirms, denies, 

 wills, imagines, feels, and which, free to follow its inclinations, should 

 render an account of its liberty. They were convinced that by such 

 meditations the soul approached the supreme power, whose direct 

 intervention appears like a continued creation. 



Belonging to the same school of philosophy, they enjoyed discussing 

 together such questions as the following : Attraction, which sustains 

 the stars in space, who knows its nature ? Affinity, which connects 

 the molecules of bodies, is it not a word whose sense escapes us? 

 We represent matter as composed of atoms; are we sure that these 

 atoms exist ? The physiologist describes the phenomena of life ; does 

 he know in what life consists ? The geologist, who writes the history 

 of the globe of which he has only penetrated the epidermis, does he 

 know its origin and end ? If man is proud of the knowledge he has 

 acquired, should he not be humble in view of what he has yet to learn ? 



The publications of our associate are numerous, and attest the activity 

 of his mind as well as the extent and accuracy of his information. But 

 an eminent physicist, M. Soret, is preparing a, complete history of 

 them in his native land, and in this article I can only notice a few of 

 their principal features, and, in particular, his beautiful theory of the 

 aurora borealis. 



The chronicle of Louis XI reports that, on the 23d of July, 1461, a 

 meteor appeared " of such color and brilliancy that it seemed as if all 

 Paris was in flames;" it adds, in consternation, "May God preserve us !" 

 On the 18th of November, 1465, a similar appearance produced like 

 terror. The king, Louis XI, mounted his horse aud rushed to the walls, 

 and the city guard were assembled and posted. The country at that 

 time was in revolt against the government, and it was supposed that 

 the enemy before Paris were attempting to iire the city. 



We ourselves witnessed a similar excitement, caused by the appearance 

 of the aurora, during the siege of Paris by the Prussian army. Prom 

 the beginning of the night until the first actual appearance of the phe- 

 nomenon, a glow was observed in the north, which gradually deepened 

 into a rose-tint, and spread over half the sky. From time to time col- 

 ored rays shot forth, of a deep blood-red, while spots of the same 

 sanguinary hue appeared here and there above thxj city. When the 

 phenomenon had reached its height, and the sky commenced to darken, 

 suddenly the red color shone out again with frightful brilliancy. The 

 next evening the appearance was repeated with somewhat less intensity, 

 but accomi^auied by luminous white radiations toward a center near the 



