234- Intelligence and Miscellaneous Articles. 



necessary to be kept in view in order to obtain a correct aralysis.- 

 Poggendorff's Annals, 1836, No. 2. 



NOTICE OF THE LIFE AND CONTRIBUTIONS TO SCIENCE 

 OF THE LATE M. NOBILI. 



The following notice of the scientific labours of M. Nobili, from 

 the pen of Professor A. de la Rive, is translated from an article in 

 the Bibliothegue Universelle. 



" It is with a feeling of the deepest grief that we announce the loss 

 which science has recently experienced in the person of the Chevalier 

 Leopold Nobili of Reggio. This distinguished natural philosopher 

 died at Florence, on the 5th [17th?] of August 1835, at an age which 

 gave the hope of a still longer continuance of his life: it appears 

 that he sank under an affection of the chest. This loss, felt by all the 

 learned world, is especially so by the editors of the Bibliotheque 

 Universelle, to which M. Nobili was in the habit of consigning his 

 important researches. Our journal has had the advantage of making 

 known the first labours of the learned Italian, and of publishing 

 thenceforward successively all the others. We therefore believe that 

 we obey a sacred duty, and discharge the debt of a very natural 

 gratitude, in endeavouring to recall in a few words the principal 

 services which M. Nobili has rendered to science, 



"After having occupied himself with investigations respecting mag- 

 netism and light, purely theoretical, M. Nobili began in 1825 to devote 

 himself to experimental researches. He commenced by inventing 

 the galvanometer with two needles, which has since rendered such 

 great services to experimental philosophy, and which has been 

 generally adopted ; its description will be found in the Bibliotheque 

 Universelle, vol. xxix. p. 119. More recently, he added to this first 

 invention that of the comparative galvanometer. But the series of 

 investigations which in an especial manner made M. Nobili known 

 to the learned world, was that relative to the colours developed 

 upon metallic plates acting as poles in the electro-chemical decom- 

 po.siiion of different solutions. The discovery of this brilliant pheeno- 

 menon, the study of all the circumstances which accompany and 

 modify the production of these coloured rings, were the object of two 

 important memoirs, which, inserted at first in vols, xxxiii. and xxxiv, 

 of the Bibl. Univ., were afterwards republished in most of the scien- 

 tific Journals. 



" It was while pursuing the examination of this subject, that M. Nobili 

 succeeded in demonstrating the cause of the electro-chemical motions 

 of mercury, (Bibl. Univ vol. xxxv. p. 161,) and in discovering in 

 the de-formation which the coloured appearances undergo in certain 

 cases, the existence of a reciprocal action exerted by electrical currents, 

 and analogous to the interference of luminous rays. {^Bibl. Univ. 

 vol. xxxvi. p. 3.) Some years later, he resumed the questions 

 which related to the form and the production of these electro-chemi- 

 cal appearances, and succeeded in employing them as a valuable 

 criterion to follow the elementary electrical currents in their progres.s^. 



