Point of Shuttle Entering Loop of Needle Thread
Fig. 11 shows the first stage in stitch formation. The thread leading to the needle is loosened, because the thread take-up lever has begun its descent; the needle, after having descended to its lowest point, has been slightly raised and a loop of thread is thus formed which is immediately entered by the point of the shuttle. The oscillating shuttle makes part of a revolution during the beginning of each stitch, the direction being indicated by the arrows in Figs. 11 and12, and during the completion of the stitch the direction of the shuttle is reversed as shown by the arrows in Figs. 13 and 14.
Loop of Needle Thread Enclosing Bobbin Case
Fig. 12 shows the second stage. The loop of needle thread has been taken down by the point of the shuttle and is being passed around the bobbin case containing the bobbin of under thread, sufficient enlargement of the loop having been permitted by the descent of the thread take-up lever.