Canadian Red Ensign, 1873-1892 pattern.
The flag has a shield within a central white circular medallion, with a Queen's Crown above, and a beaver amongst oak leaves beneath; bearing the arms of the Canadian provinces of Ontario, Quebec, New Brunswick, Nova Scotia, Manitoba, British Columbia and Prince Edward Island. 
The design dates from the period after Prince Edward Island joined the confederation in 1873 and before British Columbia changed its arms in 1896. The Manitoba St George's cross does not have a central crown on this version. 
The red ensign was used as an unofficial Canadian national flag from about 1870. From 2 February 1892 official permission was given for the Canadian red ensign to be used by merchant vessels registered in the Dominion. The version worn at sea seems to have been the same as that illustrated in 'Drawings of the flags in use at the present time by various nations' (Admiralty 1889). This had a shield divided quarterly with the arms of Ontario, Quebec, Nova Scotia and New Brunswick. The version with the arms of the seven provinces continued in use on land and additional provincial arms were added. In 1921 the Dominion was granted a Canadian version of the Royal Arms and this was in offical use on both red and blue ensigns until 1957.
A similar, but smaller, example in the National Maritime Museum, Greenwich (UK).
Dimensions: 6' by 11’ 7’’