On Saturday, June 11, we had the pleasure of making another trip up the North River with Ebenezer Barrows, Esq , in his beautiful little steamer t: Rotary," and from her performance on this occasion, we see no reason to alter the opinion expressed in No. 3, of the present volume, which was written aiter the first trial trip of this little boat last summer. The boat has made frequent trips since that time, and the engine, although nothing has been done in the way of repairs, and not a screw has been disturbed, woiks even bet ter than on that occasion, when we ielt called upon to express our admiration of the smoothness, ease, and silence of its movements. Not a sound being audible but the escape of the exhaust steamthe engine working on the high pressure principle. It is believed that the packing fits better now than when it first started. It must be remembered that this is the first engine ever constructed on this prin-ple, with the exception of one so small as to be a mere toy, and though it has been usual to make allowance for the defects of a first machine of peculiar construction, it is not necessary in this case to do so. In our first notice of the vtRotary,J; we gave the dimensions of the engine, recapitulation of these is therefore unnecessary, farther than to remark that the whole area of the steam surface operated upon at one time, is but 54 square inches, and the average pressure of steam on this occasion was certainly not more than 60 lbs. per square inch ; we should think much less, but as it varied considerably during the trip ; we cannot be positive. It must be admitted that the above area of steam surface is very small to propel a boat oi 70 ieet length and proportionate beam, draught, c , yet during some portions oi the trip, the speed obtained, consi derably exceeded ten miles per hour, the engine at the same time working pump and blower. The consumption of fuel is very small, we are informed about 110 lbs. per hour. One of the most remrkable features in the operation of this engine is, if we may so express it, its perfect obedience to command, the reversal being effected by simply changing the position of one handle, which changes the direction of its revolution without any clatter, or indeed the slightest perceptible sound or jar. The trips made by the Rotary have established the fact that this engine perlorms its duties with a very small expenditure of fuel, that its operation may be controlled by a child, and that it will run for a very long time without repairs. As it may be constructed cheaply in the first instance, it may be said to possess all qualities desirable in an engine. See engravings of this engine in No. 4, Vol. 8, Scientific American.