Edwards engines were designed by the brothers M.F. and W. Edwards of Bolton, UK and were built by H.W. Cowley & Co., also of Bolton. The two-cylinder and four-cylinder engines below were designed and built to power the Avro applications mentioned below. These two engines were more commonly known as Avro engines, apparently because of the close association between A.V. Roe and the Edwards brothers, see the comment below for the O-125 in the J1912 reference. Angle (Ae39) was not aware of this and lists the two-cylinder engine under both entries. The relationship between Roe and the Edwards brothers is discussed in the well-illustrated book by Goodall & Tagg (G&T) along with the applications below.
O-125 (2-Stroke) -- {4.016 / 5.000 / 126.7} / {102 / 127 / 2076}
Same bore and stroke as O-255, O-380, O-505.
2cyl; N/A; 15hp@1000rpm; 1910-1914; Wt = 90#.
Dual-ignition engine.
Ae39 (under Edwards and Roe); G&T (for applications); J1912 (under Avro, including photo with "AVRO" on the crankcase front).
Applications: (UK) Avro Farman-type biplane of 1910, Avro monoplane design of 1910 (not built), Avro biplane design of 1910 (not built); Bland (Miss Lillian E.) Mayfly biplane of 1911 (not completed; engine sold to Windsor); Windsor #3 biplane of 1913 (designed by Sydney Camm; not completed).
O-255 (2-Stroke) -- {4.016 / 5.000 / 253.3} / {102 / 127 / 4151}
Same bore and stroke as O-125, O-380, O-505.
4cyl; N/A; 30hp@1000rpm; 1910; Wt = N/A.
Dual-ignition engine.
Ae39; G&T (for applications).
Applications: (UK) Avro monoplane design of 1910 (not built), Avro biplane design of 1910 (not built).
O-380 (2-Stroke) -- {4.016 / 5.000 / 380.0} / {102 / 127 / 6227}
Same bore and stroke as O-125, O-255, O-505.
6cyl; N/A; 45hp@N/A rpm; 1911; Wt = N/A.
Ae39.
Applications: None found.
O-505 (2-Stroke) -- {4.016 / 5.000 / 506.6} / {102 / 127 / 8302}
Same bore and stroke as O-125, O-255, O-380.
8cyl; N/A; 60hp@N/A rpm; 1911; Wt = N/A.
Ae39.
Applications: None found.