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 K (Parii, ISSSl., IBOSI.udnKii

Bummariied his Ufa by sajin^ that, in a few y«an of incredibla activitv, he had laid out woric for geaera- tiona. An able scnolar and an orator of the first order, Lavigerie was also a. writer. Beaides some scholastic productions destiuad for his pupils at the Ecole des Cannes (184H), we have from his pen a doctorate thesis: "EBsaisurl'ficolechr^tienned'Edesse" (Paris, 1850); several contributions to the '-' Bibilotb^que pieuse et instructive & I'usage de la jeunesae chj^ tienne" (Paris^ 1853); "Ezpos^ des erreurs doctrin- aiee du Jana^niame" (Paris, 18CS), an abridgment of his leesons at the 8orbonne; "Decreta concjlii pro- vincialis Algeriensis in Africa" (1873); a large num- ber of discourses, pamphlets, or reports, some of which were embodied m the two volumes of his "(Euvrea choisies" (Paris, 1834); " Documents pourlafoodation de I'ceuvre antiesclavadste " (St. Cloud, 1889), etc. BauhiIIITi, Le Cardinal Lamgirit iPaiia, 1896 and ISBR): Kleih, Lt Cardinal Lavittrit rt tta amra (FAfrtfut (Toara, 18DI and 1897); de LAcaysE. Lt Card, liavietHt In Lt Comt- madanl [Sept.. 1900): DE Coucville, Lt Cardinal Lavigiria iPam. 1905) -.P tan, U Cardinal lAivigirit. la Ti dottrint in Bioira SactrdolaUi CatUrmpommt*

Cbubsenmiyeii, Vingl-cinii annirt d'tjiiicoait

S« atw PioLrr, Let Mutiont d'Afrimu (Pu^ IBOS),

poriwlicfili H tte RuUHin dra Munotu d-Algtr. the Mi*linu d' Afriipie dtt Pirn BlatKM, the Buli^in official d* la SacCtUanti- tKlavagiite dt France,

3. F. SOLUBB.

Lavigne, Chables. See Trincomali, Diocksb or.

Lavoisior, ANToiNE-LAintENT, chemist, philoao- pher, economist; h. in Paris, 26 August, 1743; guillo- tined 8 May, 1794. He wwi the son of Jean-Antoine Lavoisier, a lawyer of distinction, and Emilie Punctis, who belonged to a rich and influential family, and who died when Ant^lne-Laurent was five years old. His early years were most carefully guarded by his aunt, 'Mile Constance Punctis, to whom he was devotedly at- tached; and through lier asaiijtance he was secured the advantage of a good education. He attended the Col- Uge Mazarin, which was noted for its faculty of science, and here he studied mathematics and astronomy under Abb£ dc la Caillc, who had built an observatory at the college after having won renown by^neasuring an arc of the meridian at the Cape of Good Hope, by determining the length of the eeoond's pendulum, and by his catalogue of the stars. Young Lavoisier also received instruction from Bernard de Jussieu in botany, fromOucttardingcologvand mineralogy, and from Rouelle in chemistry. In logic he was inmienced by the writings of Abb^ de Condillac, as he fre<)uently aeknowledRca in his "Traits EltoentairedeChimie. He began hia career by entering the profession of tho law, but soon abandoned this to return to his favourite studies of chemistry and roineralogy. His first scien- tific communication to the Academy was upon the composition and properties of gypsum and pister of Paris, and this is to-day a classic and a valuable eon- tribution to our knowledge of crystallixing cements. He early learned to look to the balance for teip in the definition of facta, and found its great value particu- larly when he began to study the phenomena wo now know under the terms combustion or oxidaOioa, aad reduction or deoxidation.

The most advanced chemical philosophers of his day taught that there was something in eveiy combustible substance which was driven out by the burning, that the reduction of an oxide of a metal to the metallic state meant the absorption of this substance or princi- ple, which Stahl haa called phlogiston. Lavoisier studied the teaching of the phlogistonists, but having also a mastery of physics and of pneumatic experi- mentation he became dissatisfied with their theory. He seised upon two important discoveries, that of oxygen by Priestley (1774), and that of the compound nature of water by Cavendish (1781) and by a mas- lerly stroke of gcmus reconciled disoordant appearances Sfia threw the light of day upon every phase of t^e

world's reacting elements. His theory, for a long time thereafter known as the antifdiknsts' tJieoiy, was really the reverae of that of the prntwiBtonista, ' "'raply that something pondoabk wasab-

in the weight of a metallic substance when burned was equal to the decrease in the weight of the air used; that most substances thus bummg were eon- verted into acids, or. metals into metallic oxides. Priestley had called this absorbed subetance or gas de- phlogisticated air; Scheele called it empyreal air; I*- voisier "air strictly pure "or "very respirable air" as distinct from the other and non-respirable constituent of tbeatmospbere. Later, he called it oxygen because it was acid-making (ifi't, and yftniiat).

So great a change ensued in experimental chemistiy, and in theory and nomenclature, and such a mass Of facts was co-ordi- nated and ex* plained by Lavoi- sier that he has been justly called "the father of modern chemis- try".

He was the first to explain defi- nitely, the forma- tion of acids and salts, to enunciate the principle of conservation as set forth by chem- ical equations, to develop quantita- tive analysis, gas analysis, and cal- orimetry, and to

iNE-L*oaiNr Latoisieb

creat« a consistent system of chemical nomenclature. He made deep researches in oiganie chemistry, and studied the metabolism of organic com- pounds. His memoirs and contributions to the Acad- emy were of extraordinary number and variety. His life in other fields was romantic, full of interest and a ■ocial triumph, but sadly destined to end in tragedy. Happily manied, and having (he aid of his wife even to the extent of employing her in the prosecutbn and recording of his expenmente, he drew around hie fire- tude and to his libraiy at the State Gunpowder Works a circle of brilliant French savants and distinguished travellers from other lands. Early in his career he felt the need of increasing his resources to meet the necessities caused by his scientific experiments. With this in view he Iwcame a deputy /ermier-gfni'ral, whereby his income was much incrcssed. But joining this association of State- protected tax-collectors Old V prepared the way for many years of bitt«r attack and a share of the public odium attaching to their privilege. He headed many public comnussions ro-

Suiring scientific investigation, he aimed at bringing ranee to such a state of agricultural and industritu expansion that the peasant and the working-man would have profitable employment and the small landed proprietor relief froKi burdensome taxes hitherto purposely increased to make grants to corrupt favourites of the Court, Having incurred the hatred of Marat he found himself, together with his fellow /(Tmterj-ffinfraJ, growing more and more unpopular during the terriole days of the Revo- lution. Finally in 1764 ho was imprisoned with twenty-seven others. A farcical trial speedUy fol- lowed, in which he was charged with "incivism" in that he had damaged public health by adding water to tobacco. He and hia companions, amongst them Jacques Alexis Paulie, bis lathei^in-law, were con-