"This is a splendid days work," said Luke Dillon. "This crime will now be fully exposed. The plot will be unraveled and guilty brought to punishment." "Everything is progressing in the right direction," said P. W. Dunne, one of the closest friends of the dead man, "I am the last man to gloat over a fallen foe, but Alexander Sullivan's arrest comes none too soon." ALEXANDER SULLIVAN'S EVENTFUL LIFE. Alexander Sullivan had been a conspicuous figure in Chicago's political life for some time, and a few years before had been a prominent figure in two of the most exciting murder trials ever witnessed in that city. Many persons believed, from the active part which Alexander Sullivan has taken in Irish affairs, that he was by birth an Irishman. He was a native of Amherstburg, Ont., where his father was stationed in the British military service. He went to Detroit in his youth and was engaged for a time in the boot and shoe store of A. J. Bour. Subsequently he set up in the same trade for himself, his store being in the Bresler Block, on Michigan avenue. He was not a success in the business, and his career in it was ended by the destruction of the establishment by fire, the work of an incendiary. It was charged by his enemies that he set the fire himself, but an investigation failed to fasten the guilt upon him. Before this time he had made himself conspicuous in the trades unions as an advocate of the labor movement, then quite strong. In the political campaign of 1868 he took the stump for the Republican candidate. He was a polished and forcible speaker, and did excellent service throughout the State. His political course greatly offended his Irish brethren, nearly all of whom were Democrats, and they denounced him with great vigor. Soon after the installation of President Grant he was appointed Collector of Internal Revenue at Santa Fe, N. M., but was not confirmed. Subsequently, however, he was made Secretary of the Territory. He established a Republican paper at Santa Fe, and published it for some time. He became embroiled in several quarrels in the Territory, and was once shot at by Gen. Heath. He was next heard of in this city, where he was connected in a reportorial capacity with the _Inter-Ocean_ and the _Times_. In 1873 he was made Secretary of the Board of Public Works, and held it for some time.