In setting brasses or any other journal-boxes to be bored, place a piece of sheet-tin between the joint of the brasses, and bore the brasses or boxes the thickness of the tin too large, which thickness may be gauged by placing a small piece of the same tin under the leg of the inside calipers when trying the bore. The reason for this is that practice demonstrates it to be an invariable rule that a half-circle or half-hole, whether in a movable brass or in a solid box, will never fit down upon its journal, but will bind upon the edges across the diameter, and must therefore be scraped or filed on the sides to let the crown down. This defect is obviated by the employment of the sheet-tin as described, which will save three fourths of the time usually required to fit such work to a good bearing. This plan is highly advantageous in boring eccentric straps and large brasses; and the larger the size, the thicker the tin may be.