CASSIDY, William, journalist, born in Albany, New York, 12 August, 1815; died there, 23 January, 1873. His grandfather had settled in Albany when he came from Ireland in 1780. His father, John Cassidy, sat for years in the municipal board, and was an intimate friend of DeWitt Clinton. William began his education at the Albany academy under Dr. T. Romeyn Beck, and was graduated at Union in 1834. He studied law in the office of Judge James NcKown and John Van Buren, and was admitted to the bar. In 1840-'2 he was state librarian, and at this time began political writing, contributing anonymously to several papers. In the spring of 1843 he became part owner and sole editor of the Albany "Atlas," a democratic daily, which had been established a short time before. In that place he speedily made a reputation. The "Argus," which was the old organ of the democracy, founded in 1813, spoke for the hunkers. Edwin Croswell was editor. The "Atlas," representing the weaker faction, struggled with poverty and hardship. But the young editor gave it his best power and industry, and it fought a vigorous battle. He wrote often on a poor table, in a dirty corner, amid the confusion of the composing-room; but his articles bristled with sharp points and caustic wit. The battle was at its height in 1848, when Lewis Cass was the presidential candidate of the regular democracy, and Martin Van Buren held the standard of the barn-burners. The conflict died out, and in 1856 the "Atlas" and "Argus" were united, and Mr. Cassidy became editor of the joint concern. In 1865 he changed the name back to "The Argus," and organized a stock association. He was for many years one of the knot of democratic politicians that ruled the destinies of that party in New York state and sometimes in the national conventions, and to which had descended the name of the "Albany Regency," formerly enjoyed by Croswell and his associates. The principal members were Dean Richmond, Peter Cagger, and William Cassidy. On the death of his brother-in-law, Peter Cagger, in 1868, Mr. Cassidy became his successor as secretary of the democratic state committee, and held that place till the day of his death. He was invariably on the committee on resolutions, and many of the adroitest resolutions that have been attributed to others were, in reality, the product of his brain. The celebrated antislavery plank that was read and defeated at the Herkimer convention was from his pen. Mr. Cassidy was disinclined to enter public life, and the few offices that he held were forced upon him. In 1846 he was nominated in the democratic legislative caucus for state printer. In 1867 he was elected to the constitutional convention, and in 1872 was one of the sixteen appointed by Governor Hoffman on the commission to revise the constitution. He was a fine classical scholar, and conversant with French, German, and Italian. He knew books and authors almost as well as he understood politics and politicians, and he was a fine conversationalist. His death evoked expressions of sorrow even from his political opponents.