A Grindstone. (A.) A grindstone of good quality, from 20" to 26" in diameter, is indispensable to a woodworking shop, and should be used frequently, as the efficiency of cutting tools is much increased if they are kept well ground, and much time may be saved in whetting them.

(B.) In selecting a grindstone, be sure that it is true and round, and of a coarse, even grit, which can be quite satisfactorily determined by examining several and selecting the coarsest, as that will doubtlessly be a fast cutting stone.

(C.) The stone should be carefully centered and mounted upon a frame. The face may be kept true by means of a file or other hard steel being held against it as it revolves, or a piece of J" or 3/4 " gas pipe revolved from side to side of the stone as it is turned. Never allow a stone to rest with one side in the water, as it will be made softer and heavier upon that side, and soon worn out of true.

(D.) Do not use one place upon the surface of the stone continuallv, as a groove will quicklv be worn there; instead, keep the tool moving from side to side. If properly cared for, a stone will hold its face indefinitely.