Our engraving represents an improved lamp filler called by its inventor the “ Automatic Lamp Filler,” which provides for the influx of air, as the oil is poured out, obviating the inconvenience caused by the lack of a vent in the old style of lamp fillers. A small tube, B, leads from the vent in the nozzle of the filler back to the breast of the can, which- ii penetrates. This tube is soldered to both nozzle and breast of the can, and forms not only a strong brace but permits the air to enter while pouring out the oil. The ordinary cap, or a cork thrust on to the nozzle. in the ordinary way stops at once bothnozzle and vent. This lamp filler was patented, through the Scientific American Patent Agency, Oct.. 19, 1869, by H. W. Staples of Saco, Maine, for State rights' or licenses to manufacture, address Howard Tilded, 63 Cornhill, Boston, Mass. THE mechanical condition of surfaces does not wb!:>lly determine friction. Much depends upon the adhesive attraction of bodies, as to whether fricteon will be a maxiJrm or minimum.