li 



lectures on geometry to the artisans of the place, and thereby contributed 

 largely to the establishment of those courses of public lectures that have 

 brought the most fertile results of scientific research within the grasp of 

 the whole nation. In addition to these labours he wrote his ' Traite des 

 Proprietes Projectives des Figures' (1822), 1 Cours fie Mecanique applique 

 aux Machines' (1826), and many memoirs on Geometry and Applied 

 Mechanics in Gergonne's andCrelle's journals. He also invented a draw- 

 bridge with a variable counterpoise, and an undershot water-wheel with 

 curved buckets, now known throughout Europe by the name of Poncelet's 

 wheel, which nearly doubles the useful effect of a given water-power. 

 He was promoted to the rank of Chef de Bataillon in 1831, and became 

 a Member of the Institute in 1834. From 1835 to 1848 he was on the 

 Committee for constructing the Fortifications of Paris, and was successively 

 appointed Professor of Mechanics at the Sorbonne and at the College de 

 France ; became Lieutenant-Colonel in 1841, Colonel in 1844, and General 

 of Brigade on the 19th of April, 1848. A few days later he was ap- 

 pointed Governor of the Ecole Polytechnique, a post which he held till 

 1850. During the troubles of June 1848, placing himself at the head of 

 the pupils of the Ecole Polytechnique, he led them through the barricades 

 to the Luxembourg, where they formed a guard of honour for the pro- 

 tection of the Provisional Government. For this important service Gene- 

 ral Cavaignac appointed him to the command of the National Guards of 

 the Department of the Seine. He was also elected a Member of the Con- 

 stituent Assembly. As President of the Scientific Commission sent to 

 the English Exhibition of 1851, he drew up a Report on the progress of 

 the Arts involving the application of Science during the last half cen- 

 tury. Besides the works already mentioned, he wrote a large number 

 of Memoirs and Scientific Reports in the Memorial du Genie, les Avis 

 du Comite des Fortifications, and the Comptes Rendus. He was Grand 

 Ofncier of the Legion of Honour, Chevalier of the Prussian Order " Pour le 

 Me'rite," Corresponding Member of the Academies of Berlin, St. Petersburg, 

 Turin, and of many other learned Societies ; his election as Foreign 

 Member of the Royal Society took place in 1842. After a long and 

 painful illness, he died in Paris on the 23rd of December, 1867. 



Nathaniel Bagshaw Ward, F.R.S., F.L.S., who died on June 4th 

 1868 in his 7/th year, was a sound practical botanist, and was especially 

 known as the inventor of the closely glazed cases for the growth of plants, 

 which bear his name. When quite young he evinced a taste for natural 

 history and made his little collections of plants and animals. A voyage to 

 Jamaica when he was thirteen years old, and the contemplation of the 

 luxuriant vegetable life of that island, inspired him with an ardent love for 

 the science of botany. He was educated to the medical profession, and 

 for many years of his life was engaged in its practice in the east end of 

 London. His leisure time, however, was devoted to the study and culti- 



