The accompanying engravings illustrate a new and very simple form of gas engine, the invention of J. A. Ewins and H. Newman, and made by Mr. T. B. Barker, of Scholefield-street, Bloomsbury, Birmingham. It is known as the "Universal" engine, and is at present constructed in sizes varying from one-eighth horse-power--one man power--to one horse-power, though larger sizes are being made. The essentially new feature of the engine is, says the _Engineer_, the simple rotary ignition valve consisting of a ratchet plate or flat disk with a number of small radial slots which successively pass a small slot in the end of the cylinder, and through which the flame is drawn to ignite the charge. In our illustrations Fig. 1 is a side elevation; Fig. 2 an end view of same; Fig. 3 a plan; Fig. 4 is a sectional view of the chamber in which the gas and air are mixed, with the valves appertaining thereto; Fig. 5 is a detail view of the ratchet plate, with pawl and levers and valve gear shaft; Fig. 6 is a sectional view of a pump employed in some cases to circulate water through the jacket; Fig. 7 is a sectional view of arrangement for lighting, and ratchet plate, j, with central spindle and igniting apertures, and the spiral spring, k, and fly nut, showing the attachment to the end of the working cylinder, f1; b5, b5, bevel wheels driving the valve gear shaft; e, the valve gear driving shaft; e2, eccentric to drive pump; e³, eccentric or cam to drive exhaust valve; e4, crank to drive ratchet plate; e5, connecting rod to ratchet pawl; f, cylinder jacket; f1, internal or working cylinder; f2, back cylinder cover; g, igniting chamber; h, mixing chamber; h1, flap valve; h2, gas inlet valve, the motion of which is regulated by a governor; h3, gas inlet valve seat; h4, cover, also forming stop for gas inlet valve; h5, gas inlet pipe; h6, an inlet valve; h8, cover, also forming stop for air inlet valve; h9, inlet pipe for air with grating; i, exhaust chamber; i2, exhaust valve spindle; i7, exhaust pipe; j6, lighting aperture through cylinder end; l, igniting gas jet; m, regulating and stop valve for gas. [Illustration: IMPROVED GAS ENGINE]