...tow this morning, by three steam-tugs, and conveyed to a point a few hundred yards below Fort Holt, on the Kentucky shore. The huge mortar had previously been placed on board, and fixed upon one of Rodman 's mortar-carriages or beds. Ten or twelve of the thirteen-inch shells were prepared, filled, however, with wet sand, instead of powder, the object of the experiment simply being to ascertain the ra...