A simple but sturdy plain-turning round-bed lathe with a single, non-swivelling tool slide and lever-action tailstock, the "Greenly" was intended for home construction - and its design has something of a chequered history. Oddly, the was to be found advertised - for a sort time - by the Gamages Department Store in London as part of their range of small lathes - these being more commonly sourced from established makers such as Portass in Sheffield.
Although Mr. Greenly's original plans have been traced back to 1915, when it appeared as a set of drawings on page 35 of the book  Model Engineering (and also in a magazine called "Work"), the lathe became better known when, in 1922, Raymond Francis Yates, an American, published Lathe Work for Beginners in which he reproduced almost identical plans for a lathe with a double-bar bed. Although Greenly is not mentioned in the Chapter 11 lathe description, Yates did credit Greenly in the Preface n36 where he described Greenly as: "...an English authority on model engineering". Greenly was also mentioned in the Contents on n10,  but not in the index. Although Greenly's book is not yet available online, Yates's can be found at www.archive.org/details/laworkforbeginn00yategoog  Each publication contains a good deal of detailed information including all the drawings necessary to make patterns for the castings.
Although not backgeared or screwcutting, the design did allow the home builder the comparative luxury of a hand-driven feed along the bed by a leadscrew - unfortunately there was no compound slide rest, nor the ability to swivel the single tool slide to take short taper cuts, this being a serious impediment to casual use.
Greenly intended builders to use their own castings and also expected (rather ambitiously) for them to have the necessary skills to pour, in situ, white-metal bearings for the headstock and tailstock.  There was almost certainly more than one design of Greenly lathe with another version having a twin-bar bed with the leadscrew running between the rails. The lever-action tailstock design of the lathe shown in the photograph below is, apparently, different to that in the original plans..