A small glass seal with a Masonic device (set square and compasses) from the 1845 British Northwest Passage Expedition led by Sir John Franklin. The glass is rectangular mauve with the corners cut. The Masonic device is on the top. It is also inscribed with four letters. A check with the Library and Museum of Freemasonry has not found records for any of the Expedition officers.

The glass seal was found at the boat site in Erebus Bay by Captain F. L. McClintock's sledge team on 30 May 1859, as part of the search expedition led by McClintock The site had been visited and partially investigated by Lt. William Hobson on 24 May but his report does not list everything he saw or removed. McClintock records ’a glass seal with symbol of Freemasonry'. [McClintock, Voyage of the Fox (1859), page 367].

The Masonic seal was displayed at the Royal Naval Museum, Greenwich, Case 2, No. 18. 'Glass Masonic seal'. The items are also shown in - 'Stereoscopic slides of the relics of Sir John Franklin's Expedition' photographed by Lieutenant Cheyne RN, at the United Services Museum, Whitehall, No. 5 (left of centre).