Overall 26" square with a 17" square opening revealing the 16x13.75" mounted albumen photograph. This group photograph, of the British high commissioners to the Treaty of Washington, was shot by famed Civil War photographer Mathew Brady and is studio inscribed by hand beneath the photo at lower left "M. B. Brady" and at opposite right "Washington D.C.". The image itself features, l to r, Lord Tenterden, Sir Stafford Northcote, Sir John A. Macdonald, Earl de Grey & Ripon, Mountague Bernard and Sir Edward Thornton. All have hand signed boldly in the lower margin. Of note Macdonald was the first Prime Minister of Canada. Some minor toning to paper mount and several small tears in image as made and mounted by Brady's studio. Exc. Rare. Comes with Hake's COA and JSA LOA for commissioners signatures.