"a is the bobbin case; c, bobbin; b, thread wound on bobbin; d, projection from bobbin-case which keeps…
"a is the bobbin holder, partly opened to show hook b, and bobbin-case c; d, feed-points; e, presser-foot."…
A detail of the Wheeler and Wilson Sewing Machine. "s, thread-leader; t, face-plate covering...; v,…
"a, is the frame; b, shaft-crank which rocks the hook-shaft; e, receiving its motion from the double…