A Water-wonder

About three years ago an intelligent mechanic of Baltiinore began to put into shape soine ideas he had concerning water as a propelling power for vessels. He believed that by judicions manipulation a boat could be propelled without a wheel or screw. With an inventor's sublime faith in the correctness of his theory, he gave his spare moments to putting his ideas into practical form. He built a model and launched her in a trough. He "firedup" with kerosene and raised steam to work lfis pump. The experiment with the working model satisfied the inventor that he was on the right track. But botween that model and the trim little Alpha, which rau down the bay on her trial yesterday, there was a wide gulf of hope, disappointment, hard work and expectation. The Alpha is a Baltimore-built boat, eonstructed on the tug-boat model, and as neat a thing of the kind as there is afloat. She is 4:i feet in longth, and has 101 feet of beam. Slie is furnished with one 1Cliorse-power horizontal tubular boiler, and a No. 7 Knowles pump. From the pump to the stern are two lines of pipe, which strike the water about three feet beneath the surface. Two similar lines run to the bow. The pump drives through eaeh pipe a 2-inch stream, which enters the water through a ;-inch nozzle. With sixty ponnds of steam the pump makes 180 strokes to the minute, each stroke driving a stream into the body of water. This is all there is about this wonderful dervioe. And yet, under all the disadvantages of a trial trip, this was the device which yesterday enabled the Alpha to make ten knots an hour under sixty pounds' pressure. There was not a ripple astern, and no perceptible displacement of the water, except the little made by the cutting of the bow. She was baeked and turned with perfect ease. To back the boat the stream is driven through the bow nozzles, and the craft obeys ou the instant. If the bout were to Bpring aleak, the pump would simply draw ite supply from the liold and go on with its work. It is claimed that a vessel provided with this appliamoe could not sink under ordiniiry leakoge. Tor prudential reasons tliere wore no experiment in this line yesterday. A remarkable feature of the Caldwell contrivance is that the power which propels will ulso steer. To accomplish this the nozzles are worked alternately from side to side, usiug the streams as levers, on tho principie of the onr. There is yet another use to which tliis device can be applied. In case of fire on board or about the docks, a line of hose is attached to the pump, and in a second there is a floating steam engine which at least holds its own with anything on wheels. The inventor claims that his device can be profitably applied to any vesstd, although it in inainly intended for canal service, where the demand is for a cheap propeller that will not wash the banket. Mr. Caldwell declares that bcth the first and alter cost of his invention will be far less thut that of anything now in use. The entire driving apparatus is below, and no part of it could be carried away by accident or design. The whole thing is so simple that tliere is not much to get out of order, and nothing that could not easily be repaired.