The ordinary Governor, it is well known, acts on the principle of the. pendulum, a circumstance that imposes limits to its velocity, and which, in some cases, is objectionable. The governor here shown is free from this defect, and also possesses great merit on the score of simplicity and economy of construction. The theory of its action rests on the effects of momentum andthe resistance of the air,which . will be readily perceived by a slight inspection. A A is an iron frame for supporting the spindle, C, which is kept in motion by a belt running on the driving pulley, B. D D D D are four heavy metallic discs, presenting considerable surface to the air, these are fixed to the ends of inflexible bars which radiate from the bush or socket, G,this latter turns loosely upon the spindle, and can also slide up and down it. Affixed to G is the curved or spiral rod, E, whose action is simple and efficient. For when the governor is put in motion the spindle will impel the roller, F, attached to it under the spiral, which is consequently forced up, drawing with it the bush, G, and its appendages, but when the discs have acquired a velocity equal to that of the spindle, the further ascent of the spiral will cease.' Should the : speed of the spindle diminish, the velocity of the discs will not slacken on account of their acquired momentum, and in consequence their weight will induce the spiral to descend. The valve inside the valve box, M, is operated by means of a rod, J, which, by the intervention of I (constructed in the usual manner), partakes of the traverse of the bush, but not of its rotary motion. H is a stop to limit the descent of the discs, c, this stop is secured to the spindle by the pin, L. The mode of attaching the rod, J, to the valve stalk, is shown at K. The valve is not shown here, but it will doubtless suffice to observe that it is perfectly balanced, so that it works as easily under any pressure of steam as when not in use, needs no packing, cannot get out of centre, and is free from every objection that the most critical might allege against its efficiency. A governor of this description fora 100 horse-power engine weighs only 15 lbs. For fur(her particulars address John Tremper, Buffalo, N. Y. ; S. C. Hills, 12 Piatt st., New York City, Agent