IT is with deep regret that we have to record the death of Prof. Lewis Boss on October 5. While working as an assistant astronomer on the U.S. Northern Boundary Commission in 1877, Prof. Boss was greatly impressed by the urgent necessity for greater accuracy in star catalogues, and forthwith made the remedying of the defect his life work; the immediate outcome was the extremely valuable “Boss's Declinations,” in which, after discussing some hundred catalogues, he. gave the declinations and proper motions of 500 stars for the epoch 1875. In 1878 he was appointed director of the Dudley Observatory, Albany, N.Y., a position which he held until his death, and after observing the corona at the solar eclipse of that year; he settled down to the solution of the many problems involved in the rigid determination of stellar positions. Generous friends showed their appreciation of Prof. Boss's labours by providing him with anew observatory in 1893, and later the Carnegie Institution of Washington showed practical sympathy with his work, also making him director of the Meridian Astrometry Department of the Institution.