Carrying a rather ornate badge showing that it was from Lancaster,  Pennsylvania (in the north-eastern United States), the Stehmans Jenks & Stehmans lathe was manufactured by a company active between 1880 and the early years of the 20th century.
Originally known as Stehmans & Jenks, the firm were known for the selling and manufacture of watchmakers' and other small, speciality lathes - the former more robust than the usual WW type but unfortunately taking a proprietary collet, a fitting that did nothing for machine's popularity. The firm also held patents for jewellers' engraving blocks and watch-lathe attachments and were active in the manufacture of other tools for the horological trade.
Constructed with its bed, headstock, tailstock, cross-slide, carriage and tool post base in cast iron the lathe on this page was of rather light build with, for one of such small dimensions, an enormous centre height of around 5.5 inches and the use of a single, wide pulley on the headstock - the latter indicating that just one speed would have been needed for its intended operation (with the possibility of a second generated by the countershaft assembly). Indeed, the design and construction point to a machine constructed for some special process - perhaps production, light-duty metal spinning or pattern making in wood. The headstock pulley appears to be original, confirmed by the shape of the casting beneath and evidence of belt rub on the nearby surfaces. The spindle (running in tapered, watch-lathe-like bearings with hardened steel sleeves), was fitted for draw-in collets (there being no thread on its end) and with the combined faceplate, catchplate and centre being collet mounted, watch-lathe style. The collet closure handwheel appears to be lead or pewter cast onto a steel or cast-iron centre piece.
Instead of a conventional deep bed, the S.J.& S. used a relatively thin cast-iron plate with the carriage ways formed from screwed-on steel sections, that to the rear having unusual gib arrangement consisting of a strip of brass secured at both sides of the dovetail. Located in a full-length T-slot on the cross slide (there was no top slide) the enormously tall toolpost could have been accompanied by a second to the rear, allowing simple forming or parting-off operations to be undertaken.
Guided between the bed ways and located by a central slot, the tailstock was fitted with a spindle that had an unusually long travel (with a non-standard removable centre) and locked by a crude, direct-acting bolt.
Both cross-slide and carriage feed-screws were ordinary right-hand pitches, giving the usual "cack-handed" result where a clockwise rotation of the handle produced a movement towards rather than away from then operator.
Continued here