171 



DBSAIX DE VETGOCX, LODIS. 



DESCARTES, REN*. 



Philosophy at Hart Hall ; and ha ever afterwards prosecuted his 

 pliy.-ical researches with Rreat earnestness and success. Upon lii* 

 marriage in 1712, he rettlcd in London, where he wu the flrt that 

 introduced the reading of lecture* to the public on natural and expe- 

 rimental philosophy. This he did with great and continued reputation 

 to the end of his life, which terminated in 1749, in the sixty -sixth 

 year of his age. The highest personage! were attracted by the novelty 

 of liis mode of teaching ; and he waa several times honoured with 

 reading his lectures before the king and royal family. 



In 17U Dfoaguliers waa elected a Fellow of the Royal Society, of 

 which he proved a valuable member. The Duke of Chandos appointed 

 him his chaplain, and pres-nted him with the living of Edgeware, near 

 his seat at Cannons; and he wu afterwarda made chaplain to the 

 Prince of Wales. 



From some cau*es which are not well understood, Desaguliers 

 appears to have fallen into a state of great destitution ; we say 

 appears, for the authority on which the assertion rests has. so fir as 

 we know, neither received collateral proof nor denial. He certainly 

 did remove to lodgings over the Piazza in Coveut Oarden, in which he 

 continued his lecture* ; but the lines of the poet Cawthorn are the 

 only authority on which the statement of extreme indigence rests : 



" Here peer neglected Dctaguliers fell ! 

 How he who Uught two gracious kings to view 

 All lloyio ennobled, and til Bacon knew, 

 L>i'-<l in a cell, without a friend to save, 

 Without a guinea, and without a grave ! " 



If this statement be true, he must either have been tho dupe of 

 others to a great extent, or singularly improvident in his own affairs ; 

 aa beside* his emolument* from his lecturing, he held two church 

 living*. 



The separate writings of Desaguliers contain on elegant exposition 

 of the more popular portions of experimental philosophy. His mind 

 was more fitted for the popular and the practical than for the pro- 

 founder inquiries into those branches of science ; and for the geome- 

 trical method of investigation than for the higher and then new 

 calculus which has since so completely changed the whole current of 

 research. His works are 1, 'A Course of Lectures on Experimental 

 Philosophy,' 2 vols. 4to, 1734. 2, ' An Kdition of Dr. David Gregory's 

 Klcn.euU of Catoptrics an<l Dioptrics, with an Appendix on Reflecting 

 Telescopes,' 8vo, 1735. This appendix contains some original letters 

 betw< en Sir Isaac Newton and Mr. James Gregory relative to these 

 telescopes, which are worthy of attention. 3, ' A Translation of the 

 -, valuable, and little known Treatise on Perspective,' by 

 SGravesande, Svo. 4, 'A Translation of S'Graveaande's Natural 

 Philosophy,' 2 vols. 4to, 1747. 5, 'A Translation of Nieuwentyt's 

 Religious Philosopher,' 3 vols. Svo. Several respectable papers by 

 DesaguhVrs are inserted in the ' Philosophical Transactions' from 1714 

 to 1743. 



DESAIX DE VEYGOOX, LOUIS-CHARLES-ANTOINE, was 

 born on the 17th of August 1788, at St Hiloire-d'Ayat in Auvergne; 

 liis father was a. noble, much impoverished, but of ancient descent. 

 In 1776, he was placed at the military school of Kfliat, where be re- 

 mained seven years, and then joined an infantry regiment. While 

 at school he had studied diligently, and even in the garrisons ol 

 Itriancon and Huninguen, where he was quartered on leaving college 

 ho ] rosecut* d his studies with unabated zeal. Those branches which 

 relate to military science occupied him chiefly. 



When the Revolution broke out in 17-y. young Dcgaix at once 

 adopted it* principle*, a* they were then understood ; but he protester 

 against the proceedings of August 10, for which he was suspended by 

 Carnot, and imprisoned for two months. In the summer of 1792 he 

 became aide-de-camp to Prince Victor de Broglie, in the army of the 

 Rhine. In this capacity he rendered himself conspicuous by hi* coo 

 but fearless bravery. In 1793 many general* of note were sent to 

 prison as suspected of treachery to the Repuhlic, and seven com 

 niiinders- in-chief were guillotined. All distinction at that time gave 

 umbrage, and the very esteem of his comrades, and the affection of his 

 soldiers for Detail, exposed him to great peril ; be owed his escape to 

 hi* consummate prudence; for during the whole Reign of Terror, he 

 rather avoided promotion. But hi* mother and sister were sent to 

 prinon by the Committee of Public Safety. Desaix himself was 

 suspended a second time ; but Pichegru reclaimed him for the gooc 

 uf the army, and even Saint Just supported the intercession. Soon 

 after (1794), General Pichegru having been transferred to the army o 

 >rtb, Deulx would have succeeded to the command of that o 

 the Rhine, but for the suspicion* entertained of him as a noble, and 

 bis own determination at this period to shun distinction. For the 

 next two years he was employed in defending the Alsatian frontier 

 against the Austrian*. 



In 1786 Moreau received the command of the army of the Rhine 

 Desaix, who bad remained a general of division since 1793, became bis 

 lieutenant, nd w.s employed in the roost arduous cuterpri.es. Tc 

 a entrusted the passage of the Rhine (January 1796), a most 

 difficult opi-rs'ion, l.ut completely successful Shortly after, Jourdan's 

 retreat with the army of the Sambre et-Meuae having exposed Moreau's 

 army to the whole fhock of th* Austrians undsr the Archduke Cbarlos, 

 the French commander was compelled to retreat; but his masterly 



manoeuvres extorted general admiration, and for a time raited the 

 name of Morrau to a level with that of Bonaparte. Desaix com- 

 nand-d tho left wing during this retreat, and displayed abilities of 

 he highest order. The French -till retained possession of the fort of 

 Cchl, on the right bank of the Rhine ; L)omix wu ordered to <1 

 t, and arrest the progress of the enemy. Hero, amidst broken and 

 uined fortifications, this energetic officer delayed the advance of the 

 rch Hike for two months, refuting to capitulate, until January 1 T'.'T, 

 when all his ammunition was spent. Toward* the end of this cam- 

 >aign he was severely wounded, and laid up for three nfonths at Stras- 

 jouri?. The armistice of Leoben oocurre I during his confinement. 



Desaix, who had watched step by step the memorable campaign in 

 Italy, bad conceived the greatest admiration fur the gi-nim of 

 <arte, and wa< desirous of studying his tactics on the actual ground 

 where the battle* had been fought He was sent by Moreau, at his 

 own request, on a mission to that general, whom he join, .1 .,t Milan. 

 Bonaparte announced, among the order* of the day, ' The brave 

 General Desaix is come to visit the army of Italy." Thence dated 

 that close union and friendship which was only terminated by the 

 fatnl ball at Marengo, three ye irs later. 



The French republic having resolved on the invasion of 1 J 

 in the beginning of 1798, the conduct of the expedition was ent: 

 to Bonaparte, General Destiix being appointed quarter-master-gfiieral. 

 The command itself devolved upon him for several mouths, during 

 which he exhibited that energy, activity, and administrative talent, in 

 which he was allowed by his chief to excel all the other republican 

 generals. Some time after, the difficulties and hazards of tin 1 in 

 caused the enterprise to be postponed; at least as faros concerned 

 Great Britain. 



During the campaign in Egypt in 1793 and 1799, the reputation of 

 Desaix rose to it* highest point, and the conquest of Egypt has been 

 considered Ms greatest achievement. With a small band of troops, 

 and no other supplies than were to be found in an uncivilised region, 

 Desaix reduced the whole province to submission in less than a year. 

 The fertility of his resources waa incredible ; his power of winning 

 and controlling the people he couquered. unprecedented; the inhabit- 

 ants called him the Just Sultan, whilst his own suldieri compared 

 him to Bayard. Nor did this intelligent commander neglect his own 

 instruction at the sime time ; he employed the intervals between his 

 battles in visiting all the remarkable place*, ruins, and monuments in 

 that ancient land. Having completely subdued Upper Egypt in eight 

 months, be bejau immediately after a much more arduous labour; he 

 formed a regular government, and opened commercial channels with 

 the Arab tribe*. Bonaparte, before leaving Egypt for France, desiring 

 to mark his high sense of these great services, sent Desaix a sword, 

 with this inscription on the blade: "Conquete de la Haute Egypte." 

 He also enjoined his successor, KliSber, to send Desaix back to France 

 in the following November. 



Having reached Toulon on tho 3rd of May 1800, he was juet in 

 time to take prt in the battle of Marengo on the 14th of June, when 

 he was killed by a musket-ball during a charge upon the Austrian*. 

 His death was instantaneous. The French consul adapted his two 

 aides-de-camp, Rapp and Savory, on the field of battle. A statue 

 has been erected to Desaix in the Place-Dauphine in Paris. 



(Alison; Bourrienne; Noutelte Biographit Gtnfralc.) 



DESCARTKS, liKNK, was born at La Haye, between Tours and 

 Poitiers, in Tout-nine, on the 31st of March l.WC. and died at Stock- 

 holm on tho llth of February 1050, before he had completed his 

 fifty-fourth year. 



Descartes was of noble descent, being a younger son of a councillor 

 in the parliament of Rennes. He U one of the many instance* of 

 great delicacy of constitution being combined with the highest order 

 of mind. His early education was among the Jesuit*, who had, 

 shortly previous, established one of their seminaries or colleges in 

 the neighbourhood of his father's residence at La-Fluche ; and though 

 Descartes was one of those men who would have educated him 

 the absence of all instruction, there can bo little doubt that the 

 system adopted in the colleges of the Jesuits was better calculated to 

 develop the peculiar powers of the students than any other which has 

 ever prevailed iu modern Europe. 



During bis course in the college of La-Flcehc he contracted a friend- 

 bliip with Marsunne, which continued to the end of the life of that 

 distinguished monk, and this circumstance doubtless tended much to 

 increase the attachment of Dencartea to mathematical and inetnphy- 

 sical studies. Algebra wa* at this time studied by few, and it had 

 acquired but little extent and power as an instrument of invalidation ; 

 whilst geometry, aa it was then cullivnt too much to run 



into a mere deduction of isolated but curious and difficult propo- 

 sitions, without much regard to the general principles upon which 

 their analysis and yuthe*l* depended, or to the nature of the funda- 

 mental principles upon which gcotuetiical reasoning was ulti 

 founded. The comparative novelty of the algebraic methods would 

 give a charm to the study in a mind constituted like that of Descartes ; 

 and an examination of its first principles, and the operations of the 

 mind in the actual development of the truths of geometry, would be 

 more likely to arrest his active mind than the men; deduction of 

 curious but necessary consequences. It in easy to conceive that hi* 

 reading and course of study iu the college would bo somewhat deaul- 



