The Low-Lipped Dustpan: A Hard Thin Edge Pressed to the Floor

"The object of my invention is to provide a dust-pan which will be so constructed as to lie close to the floor or surface from which the dust is to be taken up and wherein the receiving edge of the pan will be of a stronger material than the body portion." The pan has "feet 11, which give a forward tip or inclination to the bottom of said pan", and at the front "a plate 12 is secured, made of steel or like material or a material which is harder than that from which the body of the pan is constructed. The plate 12 is made to taper from its back in direction of its forward edge, which is quite thin and bent downward to form a curved surface 13, capable of being brought in close engagement with the surface from which the sweepings are to be removed." A spring-wire fastening holds the handle upright in use; folded down over the pan, the same loop serves "as a means for hanging the handle and the pan from any convenient support."

Weigh out 50 g of fine sand and spread it evenly over a square about 30 cm across on a smooth, hard floor. Sweep it into the dustpan with five strokes of the broom, then weigh what is in the pan. Stick one layer of masking tape along the underside of the dustpan's front edge so the lip stands higher, measure the height with the caliper, and repeat with fresh sand. Add a second and a third layer. Plot sand collected against lip height and compare the trend with the notebook.

**Lloyd P. Ray** of Seattle, Washington, filed US 587,607 on 25 March 1897; it is dated 3 August 1897. His claims cover the spring fastening that holds the handle. **Honest limits.** The notebook treats every grain as a sphere that climbs only a step lower than its radius; real grains are angular and broom bristles lift some of them. The size mix and lip heights are examples. The sand you weigh is the measurement.