A series of minor modifications were made to the machine during its long production run, the most notable was to the tension adjustment which was changed from a thumb screw on the face-plate to the top of the needle head - alongside the presser and needle bars (c1873).The machine was produced both as a hand crank and a treadle machine with various styles of cabinet work available.The Singer Company has now put this information online go to The Singer 12 and 13 have the Serial Number located on the bed of the machine at the base of the pillar.Earlier machines have dual serial numbers in this case it is the larger of the two numbers that is used. There is a little wear to the bed, but only that of use.
It is a transverse shuttle machine using a "boat" type shuttle.The tension adjustment is by way of a screw on the face plate. It is worn in the usual places and the japanning is chipped in places. The balance wheel is nickel plated and the bobbin winder has a level feed device which we understand was only fitted to machines made at the Kilbowie factory.