134 PROCEEDINGS OF THE AMERICAN ACADEMY 



devised an instrument for that purpose, which attracted the favorable 

 attention of astronomers, and was largely discussed at meetings of the 

 American Association for the Advancement of Science. The determi- 

 nation of differences of longitude by electro-magnetic signals gave a 

 new importance to the assumed value of the velocity of electricity, 

 which did not escape his practical mind. His mechanical skill enabled 

 him to apply his ideas rapidly to practice, and his great independence 

 and energy of character surmounted pecuniary restrictions which 

 would have fatally discouraged most men. In 1836 and 1837 Mr. 

 Mitchel was Chief Engineer of the Little Miami Railroad, and in 

 1848 of the Ohio and Mississippi Railroad. In 1841 he was placed 

 upon the Board of Visitors for West Point, and in 1847-8 he was 

 Adjutant-General of the State of Ohio. He was chosen Director of 

 the Dudley Observatory at Albany in 1859. 



As soon as the rebellion broke out, Mr. Mitchel pi'omptly resigned 

 the peaceful pursuits of science, in which he had achieved large honor 

 and usefulness, and gave himself, with all the ardor of his nature, to the 

 cause of his country. On the 9th of August, 1861, he was commis- 

 sioned a Brigadier-General of Volunteers, and on the 11th of April, 

 1862, as Major-General in the Department of the Ohio under General 

 Buell. At the head of an independent column, he entered Bowling 

 Green, Kentucky, in close pursuit of the reti'eating rebels, and, con- 

 tinuing his advance southward, he seized the line of railroad between 

 Corinth and Chattanooga, and established his forces in the north of 

 Alabama. He was relieved of that command in July, 1862, and on 

 the 17th of September he assumed the charge of the Department of 

 the South. He had bai'ely time to give promise of inaugurating a 

 vigorous campaign, when he was seized with yellow-fever, and, after 

 a brief illness of four days, he died at Beaufort, South Carolina, on the 

 30th of October, 1862, leaving to the world the memory of a name 

 which deserves well of science and of his country. 



James Renavick, our late Associate in the section of Technology 

 and Engineering, was descended from a Scotch family, his grandfather 

 having emigrated to the United States from Scotland. His father, 

 William Renwick, was a merchant of New York, who married a lady 

 of Scotland during a visit to that country. Professor Renwick was born 

 at Liverpool in 1702, and came to this country Avith his parents when 

 he was two years old. He exhibited very early in life a devotion to 

 books, and a remarkable capacity and power for acquiring knowledge. 



