A first day cover is an envelope (cover) with a postage stamp cancelled on the first day that the post office issued the stamp. They usually have a special postmark or cancellation. First day covers often have a decorative design (called a cachet) on their left side.
In 1983, Canada Post issued a stamp to commemorate the centenary of St. John Ambulance in Canada. The cachet shows a training demonstration from the 1940’s. The first day postmark shows the cross of the Order of St. John.
