The great inconvenience attending carriage hubs is that there is always a difficulty in keeping them well greased ; and the boxes are, when arranged so as to be easily accessible, very liable to become filled with dirt. Our engravings represent a device which, it is said, overcomes these evils, and is particularly adapted for the English mail axle, although it is applicable to light or heavy * wheels. Fig. 1 is a view of the hub with the p. invention applied; Fig. 2 shows the outside !.( end of the hub, a; and Fig. 3 a section g? through it. A is the hub, the axle box, c the lubri-;ating groove, and C a piece cast into it, riiich is let into a corresponding slot in the iub; through a hole in this passes a semi-;ylindrical tube having at the end a screw, 1 (seen at e,) and separated at Fig. 4, which also represents the box. The advantage of this is that the screw can be easily removed, and oil supplied, and in the removal it brings with it a small quantity of dirt, and by its shape it always tends to keep the channel in which it lies clean. The firm who have purchased the English patent have called it the " United States Axle Box," and by this name it will become generally known, thus taking the place of the English axle box, which is at present considered the best. It is the invention of Dr. A. C. Garratt, No. 83 Eustis street, Koxbury, Mass., from whom all further particulars can be obtained. Patented February 26, 1857.