Sold as both a "Burden" (of which maker or distributor nothing is known) and a Hercus, this interesting twin-bar-bed lathe was made from the late 1920s until the late 1930s. With its 3.5" centre height the lathe was, although relatively light in built, constructed from iron castings with solid-steel bed bars, properly backgeared (with decent-sized gears) fitted with screwcutting and a compound slide rest. In common with many similar makers during those harder times Hercus would undoubtedly have offered the model without those last three expensive fittings and with the cheapest version being a simple plain turning lathe.
If you own one of these lathes, or have any literature about them,  the writer would be pleased to hear from you.