PROPELLER WATER WITCH.--The new propeller Water Witch, of Newport, on the river St. Clair, which has been got up with a new style of gear to her propelling power, altogether different from any heretofore used on our lakes, made her appearance on Friday evening, landing at Brady's dock for a few moments. Her machinery is operated by a walking beam engine, with gearing, which, it is stated, turns the wheel at a much greater velocity than those at present in use on other propellers. At a distance the Water Witch presents a decidedly novel appearance -- the beam moving crossways of the deck, or athwartship, instead of fore-and-aft, as on side-wheel steamers. The lateness of the hour of her arrival prevented us from going on board to examine this steamer, but those who have are loud in her praise. Her model has been got up with an eye to speed, and we doubt not she will exhibit some tail running. She is intended for the Lake Superior trade, and soon will be in readiness to commence her regular trips.