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ciety was presented to Professor Clarke, and he and Professor van't Hoff received the degree of Doctor of Science from Victoria University.

John Dalton was born in 1766 of Quaker parentage. He began to teach school at the age of twelve, and supported himself through life by teaching, and later by making analyses for local manufacturers, being thus one of the earliest professional chemists. From 1793 until his death in 1844 he lived quietly at Manchester, unmarried and entering but little into society. He was made secretary of the Literary and

Memorial Tablet over door of house in which John Dalton was born.

From a photograph supplied to Nature by Mr. A. Humphreys. The inscription on the tablet reads:—"John Dalton, D.C.L., LL.D., the Discoverer of the Atomic Theory, was born here Sept. 6, 1766. Died at Manchester July 27, 1844."

Philosophical Society in 1800, was its president after 1817, and carried on his chemical work in the rooms of the society. He was a member of the Paris Academy before he was elected to the Royal Society, but finally received all the usual honors. Dalton once said:

With regard to myself, I shall only say, seeing so many gentlemen present who are pursuing their studies, that if I have succeeded better than many who surround me in the different walks of life, it has been chiefly—nay I may say almost solely—from unwearied assiduity. It is not so much from any superior genius that one man possesses over another, but more from attention to study and perseverance in the objects before them, that some men rise to greater eminence than others. This it is, in my opinion, that makes one man succeed better than another.

Yet his own life supports the theory of innate genius, for though he worked diligently to the end, his great discoveries were made while he was a young man. It is generally known that he discovered color-blindness, sometimes called Daltonism; he also did much work in meteorology, recording over 200,000 observations; he is said to have enunciated the law of the expansion of gases before Gay-Lussac; he carried on research in different departments of physics and chemistry. But of course his great discovery was the atomic theory, the centenary of which has just been celebrated. The theory, like most others, was of gradual development, but. as Dalton says in a letter to his brother in 1803, he had 'got into a track that has not been much trod before,' and this track has become the highway of modern chemistry.

Justus von Liebig was born on May 12 of the year in which Dalton formulated the atomic theory, and the hundredth anniversary of his death has been celebrated in Germany and here. In New York there was a meeting of chemists, which was addressed by President Remsen, of the Johns Hopkins University, whose laboratory has done much to carry forward the work in organic chemistry which Liebig founded; by Professor Brewer, of Yale University, one of Liebig's oldest pupils, who has continued his work on agricultural chemistry, and by Dr. Carl Duisberg, managing director of the Farbenfabriken of Elberfeld, who spoke of Liebig's influence on the chemical industries.

There will be found articles on Liebig in the third, ninth and twentieth volumes of this journal, the last being