Spencer, a long-forgotten maker (based in Hollinwood, a N.E. suburb of Manchester hard against the Oldham boundary), were specialists in overhead cranes. However, they also produced, during the 1800s and early years of the 20th century, a variety of machine tools. Amongst these were various conventional lathes (an example is shown at the bottom of the page) together with one rather interesting and unusual example, a 4" x 18" backgeared and screwing type with its carriage guided exclusively on ways that ran down the length of the bed's front face. This was not, of course, the only lathe to have such an arrangement (the Rivett 8-inch Precision and 608 models used a similar if superior system) with the design enjoying a vogue during the closing decade of the 19th century. For a small lathe (of its time) the machine was not only strongly-built but also boasted a number of useful features: a geared-down hand drive to the carriage, large micrometer dials, a well-constructed compound-slide and tumble reverse carried on the inside of the headstock casting. The backgear was mounted on an eccentric shaft and the changewheels on a bracket with twin parallel slots, an arrangement common between 1880 and 1910 and one that (in comparison with the forked design used later) made the setting up of compound gear trains rather awkward. Instead of the drive to the changewheels being by the simple means of a gear on the end of the headstock spindle, it was taken through a lower shaft geared to spindle in a manner more commonly used on larger lathes; the only advantage was the inclusion of a sliding gear to disengage the drive. One "advanced" feature for a small lathe was the use of reduction gearing between carriage handwheel and bed rack, though its design and execution, in an exposed and originally unprotected position on the outside of the apron, can only be described as crude.
The lathe must have sold in reasonable numbers and have been in production for a number of years for it spanned the time (1890 to 1920) when small lathes gradually switched over from round leather "gut" belts on narrow-section V-grooves (often chosen for treadle-drive types) to heavier-duty flat-belt drive, this being the better option when some form of motor drive was available.
  If you have a Spencer machine tool of any kind  the writer would be interested to hear from you..