CLAEK ». BEBOHEB MANDF'O 00. 817 �ant'gdevice, in which the body of ihe blank is primarily preased into ' su angular shape, with its arms extending by sharply-defined obtuse angles, whereby the subsequent straightening and anishing the blank but forces the angles further apart, and pusKes any surplus metal caused by changing the obtuse into right angles at the cornera to- wards its center. �In Equity. �Charles E. Mitchell, for plaintiff. �Orville H. Platt, for defendant. �Shipman, D. J. T&is is a bill in equity based upon the alleged infringement of letters patent granted to the plaintiff on June 26, 1867, for an improveinent in blanks for carriago thUl-shackles. The important question in the case is that of infringement. "The inveution is for an improvement in the manufacture of the article known to the trade as ' carriage 8hackles,*or 'thill couplings;' that is to say, in the device by which the pole or thills of a oarriage are hinged to the axle. The invention relates particularly to that class of shackles which consists of a horizontal plate, with a pair of vertical ears rising therefrom, between which the eye of the thill iron is hinged. The flat or body part of the article is forged with a projection at each side, forming what is commonly called the • clip,' by which the article is secured to the axle." It is necessary, in order to make a salable article, that the corners of the back or flat portion of the shackle shall be sharp and well defined. If the ears of the blank are simply bent from the body at right angles, the outer corners will be rounded by means of this bending. �Before the plaintiff's invention two different methods of forming the blank were used. One was to prepare the blank with projections of metal at the points where the angles were to be formed, so that when the bending took place thi^ sur- plus would fill out the corners with Suffioient materiel to make a sharp right angle. This method is shdwu in the patent to James P. Thorp of May 1, 1860. The second plan was to form both the angles in the blank and the back before the bending took place, and then to straighten the arms with- out changing the shape of the back or of the angles^ This v.7,no.9— 52 ��� �
