Hidden numbers in Penny Reds

Here's something that most stamp collectors don't know...there are hidden plate numbers in the margins of Britain's Penny Reds like the one shown here.

According to Wikipedia.com, "Close examination of the Penny Red [right] reveals a "148" in the margin, indicating that it was printed with plate #148. Stamps printed from plate #77 are extremely rare."

The website goes on to say, "The Penny Red, issued in 1841, succeeded the Penny Black and continued as the main type of postage stamp in the United Kingdom of Great Britain and Ireland until 1879, with only minor changes to the design during that time. The colour was changed from black to red because of difficulty in seeing a cancellation mark on the Penny Black; a black cancel was readily visible on a Penny Red."

For more on Penny Reds, click here.