Launch. - According to previous announcement, the launch of the new vessel on the stocks at Miller's shipyard, came of promptly at 10:30 this forenoon. Every preliminary having been arranged, at the above hour the last blow was given ne cessary for her change of element, and the fine craft glided gracefuly into the water. She is about 400 tons burthen, and will carry 17,000 bushels of grain through the Welland Canal. Her architect was Mr. Brower Morgan. She is named the Russian, and was constructed for Messrs. Smith & Post. The Russian is by far he most substantially built vessel ever sen from the stocks of our shipyards. She will sail for the upper lakes in a day or two, and will be commanded by Capt. Geo. Clement, an able and efficient mariner.