Steam engine makers have been- occupied ! Jor the last five or six years in discovering j plans for manufacturing steam, engines (or steam motors) which shall unitein themselvesj the advantage of being easily moved from place to place, and be capable of giving sufficient power for the Jight work of an ordina-ry machinist. This is why that, at the Exhibition at London*a large number ol machines of this kind were exhibited. In France, as in England and America, many ingenious machinists have tasked themselves to construct small engines with the machinery so simplified aa tohrender them light and easy of transportation, ? Various machines of.this kind have been in-vented; the engine being generally (though not always) separated. . '' Having thus premised and shown that it is occupy but little space, and may be easily moved from place to place, we will describe the portable engine of Mons. Keni^es, an ingenious machinist of Paris, France;— Figure 1 is an outside elevation, and fig. 2 is a transverse section. The same letters refer to like parts. First—The entire machine, including its boiler, occupies no more room than, an ordinary turning lathe. Second—It is as easy pat together as an ordinary stove, and purpose of a stove. It will be easy to see by the engravings that this engine is mounted upon the upper'surface or covet, A, ol the Toiler, E, from which the steam is conveyed at once into the cylinder, , by the tube or con-duiti C. which adapts itself to the bos, d, which is castwith this cylinder. By this arrangement the inventor says he* obtains, in the cylinder.a pressure nearly equal ?to that in the boiler, owing to their near viol-" nity, and, asa consequence, produces a certain economy in fuel, by avoiding condensation and a consequent diminution of the "pressure. The boiler, E, placed under Hie machine, is of the greatest -simplicity of construction. The furnace is constructed in the interior of the: j boiler, in such a nianner as to cauee the boiler to receive nearly all the heat generated by the fire. The smoke, upon leaving the fire, passes around the boiler by-two flirts, G (the openings to which are within the furnace), and unitein a common chimney. This chim-neyinaybe a common stovepipe, adapted'to the size of the machine, and made to answer the purpose of wariring the shop in which Iflie engine is employed. The whole of this apparatus rests upon a foundation of bricks, enclosed by a casing of sheetiron. ? Under the fire, andin the interior of the furnace, is placed a reservoir, J, from which the boiler obtaiik its supply of Water. It will oe seen thata machine of this kinti may easily be constructed from a. one mail power to a two-horse power—may be made to turn a heavy piece of machinery or a child's plaything, and may be put up, raised, or shifted from place to place, without altering -any arrangement connected with it when it was placed in its first position. The uppej* surface" of the boiler, the cover, At supports the various machinery and safety apparatus necessary to the .propulsion, such aa the float, level, safety, valve, alarm whistle, and steam gauge. ? The engravings suppose that the supply jiSimg* e, is connected withthe surface of the boiler, and the rod connected with a bow-ed shaft,/, which .gives motion to the slide I valve. This arrangement is economical, because it dispenses with notonly the handle, but also several pieces which usually serve to work the cutoff, c. ^ The engine is direct-aijng, "the piston rod jtg connected'to the double crank in the toddle of the shaft, I. The slide valve is worked by an eccentric on -this shaft, which has its bearings in the side Upport whichare braced together by the transverse beam, m. It is a very compact engine in every reepeetiand the power can be carried off and applied to ] drive other machinery by belts from pulleys on the boweol shaft. "We have translated this from " Le Genie Industriel,11 of Paris, with some slight alterations to render the matter more clear to our readers. It resembles, in a measure, the portable engine of Hoard Bradford, of "Water-town, N. Y., and is something like the one of CharlesMann,ofTroy, N.T. Portable steam engines, we know, interest a large class of our readers, and also a very large proportion oi our citizens who are not readers but should be, if thsy consulted their own interests.