19th March 1862 - December 1864 (?)
25th August, 1862,
This value was created exclusively for the prepayment of letters going abroad, especially to Belgium and Switzerland ; and it was not till the 1st April, 1865, that it became available for inland postage, there being no rate of threepence for inland letters until this date, when the letter-rate was fixed at one penny for every half-ounce, or fraction thereof.
Defective, not used
19th March, 1862
25th August 1862 (not issued)