168 



(757.) 



MATHEMATICAL AND PHYSICAL SCIENCE. 



[Diss. VI. 



Tacter. 



jji s scientific character is easily summed up. He 

 was P a ^6nt, intelligent, and devoted to science from 

 youth to age. He had, in an eminent degree, that 

 patience and tenacity of purpose and of interest 

 which Newton described as the chief attributes of his 

 own genius. He had the candour which is more 

 especially to be desired in the experimentalist ; and 

 he wrote without pretension, and generally clearly, 

 though not without that diffuseness which is often 

 associated with the use of the Italian language 

 even in matters of science. On the other hand, his 

 intellect may be rather described as opening itself to 

 jonviction, than as forcing its way by a native power 

 of penetration to great results. His taste and his 

 talent lay far more in experimental than in abstract 

 reasoning. His explanations of the effects which he 

 observed were often involved and obscure ; yet he had 

 a very happy talent of combination, which led him 



to effect what others only talked about. His instru- 

 mental inventions, including the pile, were his hap- 

 piest efforts. His theories, on the other hand, were 

 surrounded, even in his own mind, with a certain 

 obscurity. Even the contact theory, with its manifold 

 paradoxes, was perhaps only vigorously carried out 

 by him under the excitement of an active contro- 

 versy. The invention of the pile may, in very many 

 respects, be placed on a par with that of the steam- 

 engine. The results of the former were indeed more 

 interesting, immediately, to pure science; the latter 

 to the arts of life and the needs of civilization. Yet, 

 after half a century, this distinction can hardly be 

 drawn with severity. The rapid pace of steam is 

 insufficient for our demands. The electric wire con- 

 veys to its destination, ere the locomotive has time to 

 start on its journey, tidings of joy and sorrow life 

 and death of victories won, and kingdoms lost. 



3. SIR HUMPHRY DAVY. Progress of Voltaic Electricity Electro- Chemistry ; Berzelius. 

 Davy's Invention of the Safety -Lamp. WOLL ASTON; his Electrical and other Observations. 

 Contrast of his Character with that of Davy. 



(758.) 

 History of 

 the pile of 

 Volta con- 

 tinued. 



(759.) 

 Cruick- 

 shanks, 

 Wollaston, 

 Davy. 



The pile of Volta was, in one sense, rather a 

 means of discovery than a discovery itself. Volta 

 had neither a just theory of the source of power 

 which he invented, nor was he successful in applying 

 it to any important research. The discovery of its 

 chemical efficiency by Nicholson and Carlisle, stimu- 

 lated, as we have seen, for a short time his interest 

 and curiosity ; but he never seriously attached him- 

 self to this line of discovery. His subsequent papers 

 are chiefly controversial, in support of the Contact 

 theory. The generation, as well as the expendi- 

 ture of chemical forces by the pile, consequently re- 

 mained, as far as he was concerned, in complete 

 obscurity. 



The invention of the pile having been communi- 

 cated to the world through the Royal Society, natu- 

 rally gave an impulse to English electricians and che- 

 mists. The first discoverers of its chemical energy 

 did not however themselves prosecute their experi- 

 ments to a great extent, but Cruickshanks decom- 

 posed salts and revived the metals by the voltaic 

 current, whilst he improved the form of the appa- 

 ratus in an important manner. Colonel Haldane 

 ascertained the significant fact that the action of the 

 pile cannot be continued in an atmosphere deprived 

 of its oxygen. Hisinger and Berzelius, carrying out 

 Cruickshanks' experiments, showed that, generally 

 in the decomposition of compounds, the alcaline and 

 metallic elements appear to be attracted towards the 

 negative wire of the battery, and the acids to the po- 

 sitive one. In the mean time, Davy and Wollaston 

 appeared on the arena, and the former especially filled 

 so important a part in the history of science for the 

 next twenty years, that we can hardly give his name 

 too great a prominence in a review of the character- 

 istics of the period. The constitution of Davy's mind 



was also more than usually interesting, and his career 

 of discovery, short, brilliant, and decisive, is at once 

 one of the most instructive and remarkable of 

 those which we have to consider. The contrast be- 

 tween him and his contemporary, Wollaston, was 

 one of those curious antitheses of really great minds 

 which occasionally occur in such close connection, 

 and with such prominent relief, as to compel rather 

 than invite a comparison between them. It is an 

 instructive lesson to observe, how natures, the most 

 unlike, cultivated in a school the most opposite, may 

 yet, when both directed by a common impulse to 

 similar objects, promote the development of truth, 

 and the cause of scientific discovery. 



Sir HUMPHRY DAVY was born at Penzance on the g . ('60.) 

 17th December 1778. His was an ardent boyhood, phry Davy 

 Educated in a manner somewhat irregular, and with his earlj 

 only the ordinary advantages of a remote country town, hlstor y and 

 his talents appeared in the earnestness with which he a t,i e geniua 

 cultivated at once the most various branches of know- 

 ledge and speculation. He was fond of metaphysics ; 

 he was fond of experiment ; he was an ardent student 

 of nature ; and he possessed at an early age poetic 

 powers, which, had they been cultivated, would, in the 

 opinion of competent judges, have made him as emi- 

 nent in literature as he became in science. All these 

 tastes endured throughout life. Business could not 

 stifle them, even the approach of death was un- 

 able to extinguish them. The reveries of his boy- 

 hood on the sea- worn cliffs of Mount's Bay, may yet 

 be traced in many of the pages dictated during the 

 last year of his life amidst the ruins of the Coli- 

 seum. But the physical sciences those more em- 

 phatically called at that time chemical speedily 

 attracted and absorbed his most earnest attention. 

 The philosophy of the imponderables of Light, Heat, 



