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LAV patriotism cost him first his liberty and then his life. He was for some time a prisoner at Basle; and on the 26th September, 1799, he received a shot through the breast from a French soldier, when humanely interfering; to protect some poor people of Zurich from the brutality of some of Massena's drunken troops. From the effects of this attack he never recovered. On the 14th September, 1800, he spoke his last words from the pulpit of St. Peter's, and on the second of January, 1801, he died. His life was written by Gessner, his son-in-law; but a new life, exhibiting him in connection with his times, and written in a critical and historical spirit rather than for the ends of a practical biography, is still considered in Germany to be a desideratum.—P. L.  LAVATER,, a Swiss protestant divine, born at Kyburg in the canton of Zurich in 1527. In 1545 he came to Strasburg, where he studied for some time, and afterwards at Paris. He was the son-in-law of Bullinger, and became canon of Zurich, and also pastor. He died in 1586. He was the author of several works, among which are a treatise in Latin on the rites and constitution of the church at Zurich; one, "De Spectris, Lemuribus," &c., which is learned and curious; a catalogue of comets; the "Life and Death of Bullinger;" and sundry theological and expository writings.—B. H. C.  LAVINGTON,, Bishop of Exeter, was born in 1683, and died in 1762. He studied at Oxford, and became in succession prebendary of Worcester and canon of St. Paul's, and in 1747 bishop of Exeter. He appears to have been a man of some learning and more wit, and was distinguished by his zeal for the protestant succession. He is only now known by his curious book, "The Enthusiasm of Methodists and Papists compared," which appeared in 1754. The first volume is mainly directed against Whitfield, and the second against Wesley. In a continuation the author attacked the Moravians.—B. H. C.  LAVOISIER,, one of the most illustrious chemical philosophers of France, or rather of the whole world, was born at Paris on the 16th, or, according to another account, on the 26th of August, 1743. His father, a man of opulence, took great pains with his education, and placed him at the Collége Mazarin, where he showed great taste for the physical sciences, and made uncommonly rapid progress. Not being injudiciously forced into any profession or business, he was able to devote his whole time and talents to his favourite pursuits. He studied mathematics and astronomy under the Abbé Lacaille, botany under Jussien, and took lessons in chemistry from Rouelle. He showed equal abilities in the mathematics and in natural science, and for some time he felt undecided what branch to follow. Guettard, to whom the earliest geological map of France is due, wished to enlist young Lavoisier as an associate in his labours. For some time in fact he became an ardent student of geology, and one of his earliest writings relates to that science. A little before this period the Academy offered, on behalf of the French government, a prize for the best memoir on lighting the streets of Paris. In competing for this honour, Lavoisier gave a striking proof of the firmness and decision of his character. Finding, after some experiments that his eye-sight was not delicate enough to recognize the respective intensity of the flames which he wished to compare, he shut himself up in a darkened chamber for six weeks. At the end of this period his sight had become exquisitely sensitive, so as to perceive the most minute differences. A devotion to science so rare at the age of twenty-two did not go unrewarded, as the Academy in 1766 decreed to him as the successful candidate the gold medal, and two years later inserted his essay in its Transactions. In 1768 was also published his paper on the composition of gypsum, which he showed to be a compound of lime and sulphuric acid. Soon afterwards he examined the supposed conversion of water into silica by prolonged digestion in glass vessels, and proved that the deposit of silica was due to the partial decomposition of the glass. About this time he gave a fresh proof of his zeal for science. Close attention to study and neglect of exercise had somewhat injured his health, and especially his digestion. He therefore gradually reduced his amount of nourishment, and at last restricted himself for several months to a milk diet, rather than withdraw any portion of time from his favourite pursuits. In the year 1771 he finally resolved to select chemistry as the great object of his life. Bearing in mind the heavy expense which this study would entail, he sought for and obtained the post of a fermier-général. About the same time he married Marie Anna Pierrette Paulze, the daughter of one of his colleagues. He made a regular distribution of his time, devoting the mornings and evenings to chemistry, whilst the middle of the day was spent in official business, in which, to the surprise of the financial world, he acquitted himself to general satisfaction. Sunday was for him always a day of unalloyed pleasure. He spent the whole of it in his laboratory, either experimenting or conferring with the most eminent philosophers of the age, foreigners as well as Frenchmen, who eagerly sought his society. The annual expenses of his laboratory appear to have ranged from six thousand to ten thousand francs. He now commenced the execution of an idea which had been gradually dawning on his mind—the formation of a new general theory of chemistry, in place of the prevalent doctrine of phlogiston. In this he showed an amount of tact well worthy the imitation of all reformers, political and social as well as scientific. He does not attack phlogiston, he ignores—he supersedes it. He reasons as one who has never heard of phlogiston; he collects the most important facts of the science, and shows that they can be explained without any mention of that imaginary agent. In this task he had indeed forerunners. Rey, Hooke, Mayow, all knew that bodies during calcination, or what we now call oxidation, gain weight instead of losing, as they ought to have done on the phlogiston view. But these facts had been overlooked, the world not being ready to receive them, or, in other words, the evidence not being sufficiently complete. The chemists of the day, following Beccher and Stahl, still maintained that metals and combustible bodies contained a certain substance named phlogiston, with which they parted when calcined or burnt. Lavoisier, introducing for the first time the balance into regular use as a chemical instrument, seeks to render account of all the products of combustion. He sees that not only metals, but sulphur and phosphorus gain weight during combustion. Heating tin in a sealed vessel, he finds that a portion of the air combines with the tin, which in consequence becomes, as we now say, oxidized. When a certain quantity of tin is thus oxidized, no matter how long the heat is continued, the rest of the metal remains unchanged although the vessel still contains much air. At this juncture, August, 1774, oxygen was discovered by Priestley, who the same autumn, on a visit to Paris, showed Lavoisier in his own laboratory the preparation of this gas from oxide of mercury, and its leading properties. This was a most important step towards the end sought. It is, however, much to be regretted that, in the Memoirs of the Academy for 1775, which were not published till 1778, there appears a paper from Lavoisier—"On the Nature of the Principle which combines with Metals during Calcination, and which augments their Weight." Here he details the preparation and properties of oxygen gas as if it had been an independent discovery of his own, without the least allusion to Dr. Priestley. In another paper, inserted in the Memoirs for 1777, and entitled "On the Combustion of Candles in Common Air, and in Air eminently Respirable," he admits Priestley's discovery of oxygen, but without any explanation of his strange silence in the former paper. Here, besides common air, he recognizes three gaseous bodies; first, pure air (oxygen), called by Priestley dephlogisticated air, and forming, as he supposed, about a fourth of the atmosphere in volume; second, azotic or mephitic gas (nitrogen), forming the remaining three parts of the atmosphere; and third, the "fixed air" of Dr. Black (carbonic acid), which Lavoisier calls cretic acid. One difficulty yet remained. Hydrogen is given off during the solution of certain metals in dilute acids. Again, when a calx (oxide) is heated in hydrogen, the latter disappears and pure metal remains. "Well," say the chemists of the day, "hydrogen is phlogiston, and metal is calx plus hydrogen!" Lavoisier feels that this cannot be. The calx is after all heavier than the metal whence it sprang; and hydrogen, lightest of known bodies, is still not weightless. He therefore bides his time. And now, in 1783—just as he is about to examine on a larger scale what is the unknown something formed when hydrogen is burnt—come tidings that Henry Cavendish has solved the question, and that the unknown product is water! When, therefore, metals dissolve in an acid, water is decomposed, its oxygen going to the metal to form a "calx," and its hydrogen escaping. When, again, calces are heated in hydrogen, they give up their oxygen, water is formed, and pure metal remains. All is now in harmony, the whole of the phenomena are now explained quantitatively, and the chain 