R O Harrison - Shortwin
The business began in 1933, and soon produced a full range of bikes. The track model was ridden by England's Pro Track Champion and a top Canadian rider. By 1938, business had grown and the bikes became a bit more prestigious. The Lyta model featured hand-cut fancy lugwork. 1949 saw the introduction of the Shortwin model, which had two smaller side-by-side down tubes instead of a single down tube. These smaller tubes had a "D" cross-section, causing the pair to look like a single tube had been cut down the middle and split. This was supposed to increase the frame stiffness, as were the short (15.5 inches) chainstays.
as a side note, I find these uses of unusual frame configurations intriguing. Certainly people understood the basics of how a tube's dimensions affect stiffness in bending and torsion? Other details, such as the Bates Diadrant frames and dual bend forks, or the Hetchins curly stays, are hard pressed to demonstrate real value, but they still look neat and attract attention. For better or worse, modern builders such as Colnago are happy to adopt these ideas as a marketing technique. The Colnago Bi-Titan comes to mind, with its dual down tubes.
Steve in Peoria