The runner being in standing balance, place two boards planed evenly and ⅜ of an inch in thickness between the stones, (they may be 4 to 8 inches wide) allowing the ends to project sufficiently to fasten securely to a block or piece of timber fastened to the husk; place them about midway between the spindle and outer edge of stone, and put the stone in motion, letting it down upon the boards until its face runs steady and true; then turn off the plaster back perfectly true with the face, from a firm rest properly supported; now try the standing balance again. By turning off the back it may have been changed. Next find the light side of the stone by elevating the runner from the boards, and run it as fast as it will bear without too much vibration, as in cases where the stone is much out of balance the full speed should be approached gradually in the process. Hold a pencil against the rest plank and approach it slowly until it touches the turned back of the stone, say 4 to 6 inches in from the band or skirt. It will of course mark the side which runs high. The principle or real cause of this side of the stone running high is that the center of gravity or weight on this side is too low, (below the cock-head and point of suspension,) while the center of weight on the side that runs low is too high and above the center. To change this so as to bring the center of weight of each side respectively on the same level, is what we must accomplish. As we know which side of the stone was high, now take, say two to six pounds, as the case may require, of iron, broken into small pieces, or shot, and take one-half of the amount and put into the inside box screwed to the top of the box on the side that runs high, and the other half in the box or boxes opposite, and lowered by the screw into the bottom of the balance box. Then test the stone and make a new mark, add weight carefully until the face runs true up to the full grinding speed. Be careful to divide the weight, as it may be added, so as not to disturb the standing balance. Standing balance is simply an equal weight on all sides. Running balance is having the center of gravity just as far from the face on one side as the other. Irregular motion, and no matter how fast, will not affect the runner when balanced as we have explained. If this important item is properly attended to, as well as keeping the stones in good flouring face, there will be less killing of the life of flour, and allowing middlings and unclean bran to escape. The value of the flour, both as regards nourishment and health, depends on the amount of nutritious, aromatic and saccharine properties retained in the flour which the wheat contains. This result depends upon the flouring process the meal has been subjected to between the stones. On the amount of these properties in the flour also depend the weight and sweetness of the loaf when baked; likewise its light and white qualities when used for any purpose. [Illustration]