PADDLE WHEELS. The _Port Byron_ is a stern, paddle-wheel boat, with vertical or eccentric acting paddles, and is like the _Viele_ of 1858. She has a recess the entire length of her bottom of several square feet area, intended to facilitate a flow of water from the bow, but the flow does not occur; the mechanical currents of the wheel will be from the nearest water, and not from ninety feet forward. The _Montana_ is a similar stern-wheeler, without the recess. The _Success_ consists of two sections, to be disconnected for passing the locks, with paddle-wheel machinery at the bow. Her wheel, inside of the paddles, is a drum or cylinder, filled with cork, to be buoyant, and the hull has an easy, scow bow, for the water to pass under the boat. Practically, the large drum makes her a horizontal, cylindrical-bowed boat, and she mechanically throws the water therefrom against the scow-shaped bow, and so that the cylinder displacement with the mechanical currents, and the scow-bow displacement, combine to make her _very slow_. With her two sections she brought one and a half cargoes of corn. The _Excelsior_ has a horizontal, eccentric-acting paddle wheel, and was built of light iron at Green Point. She had a recess at the bow for her submerged wheel, and, when thus tried, found the retarding effects of the mechanical currents at and against the bow so great, as to cause her original bow-propulsion to be made stern-propulsion, when she was much improved. She was tried with cargo for a short distance on the canal, and withdrawn. The _Fountain City_ is a common boat, with machinery at her stern. She has two submerged horizontal, excentric-acting paddle-wheels, each of small diameter. These are placed under her quarters, in the rudder cross-section, and she is steered by her machinery. The characteristics of these wheels are like the _Excelsior's_, and the eccentric variations of both--together with the _Byron's_, _Montana's_ and _Viele's_--are known as old devices of secondary merit on river, lake and ocean steamers. The _Santiago_ is a scow-boat, with a recess, or flume, the whole length of her bottom, to a stern propeller. Her steam was soon abandoned. An endless-chain propulsion was tried upon the Western Division, without success. A common canal-boat has been experimented with at Brooklyn to propel her by the reaction of a powerful blower or fan. This was driven first by a ten-horse, and next by a forty-horse stationary engine, and afterwards by a forty-horse oscillator. Each failed to move her from her slip, and the conception proved an absurdity. In addition to these, local steamers have been run between different cities for local purposes, more or less, since 1858, and steam-tugs have been brought into requisition occasionally. OBSERVE: This review presents the important fact, that NO NEW MECHANICAL SYSTEM HAS BEEN INTRODUCED.