Probably 1st half of the 20th centurySerial number: 49.
Technical description: Calfskin membrane, badly broken around rim. Rim of metal set inside a wooden body veneered in hardwood (rosewood?). Nickel plated string holder at bottom with five knobs for the looped strings to attach to. Neck width 35.5 - 51. Mother-of-pearl frets at 1, 3, 5, 7(2), 10, 12, 14, 17, 21; 21 frets total . V-shaped neck. 5 tuners of ebony veneered head. Fingerboard of ebony over maple. Metal button on back. Tuner metal including the buttons.
Overall size: 921
Body diameter: 223 (membrane), 289 (body)
Body depth: 57
Number of tension points: 20
String length: 696
Impressed on the neck at the heel and stamped on the bass side of the head "The Windsor. 49".