The lever is made of iron or steel, and at the end is formed with a point projecting laterally slightly beyond the end of the lever. On the side of the lever is a curved arm having a point directed toward the body of the lever. The space between the points is sufficient to admit of placing the lever on a joist with the points on the opposite sides, as shown in the cut. By pushing the arm of the lever forward against the edge of the flooring or ceiling, or against a block placed on the edge of the strip of flooring, the latter can be forced into position and held while being nailed. This clamp, the invention of Mr. John B. McRae, of Mount Holly, Ark., can be quickly applied and removed, and can be made small and light, so as to be readily portable.