In the assembling and making up of narrow elastic fabrics, particularly suspenders, it is often necessary to use buttonholes in the finished products. Sometimes the buttonholes are cut and worked on the ordinary buttonhole sewing machines, but on account of the difficulty arising in the controlling of the strands of rubber when it is cut for working, a very unsightly buttonhole often results. It has therefore been found advisable to weave the buttonholes, particularly for what is known as the “Guyot” suspender, where elastic pieces having buttonholes are used for the back ends, and non-elastic straps, also having buttonholes, are used for the front straps. The loom will automatically weave the buttonholes at any desired place, and at the same rate of speed at which the plain part is woven. This is accomplished by the use of two banks of shuttles, both of which are running in the same direction at every pick of the loom, but only one of which, (the upper) is engaged with the cloth while the plain part of the goods is being woven, the other bank running “dead” underneath the goods during the operation. When the buttonhole is about to be made, two distinct sheds are formed and then the two banks of shuttles are engaged, the upper bank on one half of the strap and the lower bank on the other half, until the completion of the buttonhole. Then one shed is again formed in place of the two, and the upper bank resumes the operation of weaving the plain part of the strap. [Illustration: Fig. 5—Jacquard Suspender Loom With Two Machines and Fancy Head] This process of changing from the single to the double shed is accomplished by the use of a specially designed cam jack made in two sections, to which are attached two harness frames, in each of which one side of the strap is drawn. While weaving the plain part of the strap both sections of the cam jack operate in unison, running side by side from the same cam, but when the buttonhole is “called on” a device for spreading apart each pair of cam jacks is operated, and the two sheds are then formed. At the same time a lever movement changes the position of the lay, so that the two banks of shuttles take new positions and properly engage the two sheds. Facilities are provided for governing the length of the straps and the position and length of the buttonholes. When the lower shuttle is not engaged in the buttonhole shed, the filling may run loosely beneath the goods, and require trimming off between the buttonholes. This trimming may be avoided by operating the center binder thread, putting the same in a skeleton harness and giving it an extended shedding so that this particular thread may be dropped below the main shed and allow the lower shuttle to engage it. By this process the thread is bound in the goods at every pick of the loom and does not need trimming.