The name of Mendelssohn is too well known to the world, to make it necessary for me here to dwell long on the portraiture of the great intellectual and moral qualities of this celebrated man of our nation. I shall sketch merely those prominent features of his portrait, which have made the strongest impression upon me. He was a good Talmudist, and a pupil of the celebrated Rabbi Israel, or, as he is otherwise named after the title of a Talmudic work which he wrote, Nezach Israel (the strength of Israel),--a Polish rabbi who was denounced for heresy by his countrymen. This rabbi had, besides his great Talmudic capabilities and acquirements, a good deal of scientific talent, especially in mathematics, with which he had attained a thorough acquaintance, even in Poland, from the few Hebrew writings on this science, as may be seen in the above-mentioned work. In this work there are introduced solutions of many important mathematical problems, which are applied either to the explanation of some obscure passages in the Talmud, or to the determination of a law. Rabbi Israel of course was more interested in the extension of useful knowledge among his countrymen than in the determination of a law, which he used merely as a vehicle for the other. He showed, for example, that it is not right for the Jews in our part of the world to turn exactly to the East at prayer; for the Talmudic law requires them to turn to Jerusalem, and, as our part of the world lies north-west from Jerusalem, they ought to turn to the south-east. He shows also how, by means of spherical trigonometry, the required direction may be determined with the utmost exactness in all parts of the world, and many other truths of a similar kind. Along with the celebrated Chief Rabbi Fränkel, he contributed much to develop the great abilities of Mendelssohn. Mendelssohn possessed a thorough acquaintance with mathematics; and this science he valued, not only for its self-evidence, but also as the best exercise in profound reasoning. That he was a great philosopher, is well enough known. He was not indeed an originator of new systems; he had however amended the old systems, especially the Leibnitio-Wolfian, and had applied it with success to many subjects in philosophy. It is hard to say whether Mendelssohn was endowed with more acuteness or with depth of intellect. Both faculties were found united in him in a very high degree. His exactness in definition and classification, and his fine distinctions, are evidences of the former talent, while his profound philosophical treatises afford proofs of the latter.