In March 1843 modified Maltese Crosses were introduced to the London Inland Office of the General Post Office; this was the office that dealt with mail originating in London but destined for provincial English and Welsh Post Towns together with all of Scotland and Ireland.

These new obliterators had the addition of a number (1-12) in the centre and, with the exception of the one numbered “3”, a small cross at the top.

Various theories regarding the usage of these obliterators have been suggested, although nothing has been proved conclusively.  It is likely, however, that the Number 12 obliterator was used to cancel larger items as it is most frequently seen cancelling 2d stamps and multiples (of both the 1d and 2d stamps).

Inroduction of the Obliterator
 

The earliest recorded use of a Numbered Maltese Cross is 16 March 1843, this being with a “3” in the centre.  None of the others are recorded until 21 March 1843.
 

[RD] plate 24, from London to Hawick dated 21 March 1843,
cancelled with a black London Number 1 Maltese Cross

This pre-dates the entry in the proof book by two days
and is the earliest recorded use of the Number 1 Cross

It is one of two such covers recorded

Usage on the 1d Red
 

Usage on the 2d blue
 

Transition to Barred Numerals
 

The transition from the Numbered Maltese Crosses to the Barred Numeral Cancellations of the London Inland Office occurred o0n 17 May 1844.
 

[RB] from London to Leicester, dated 15 May 1844,
cancelled with a black London Number 7 Maltese cross

Penultimate day of the usage of numbered crosses in London

There are seven covers recorded dated 16 May 1844 and none later
 

[AI] from London to Boston, dated 16 May 1844,
cancelled with a blackLondon No 7 Maltese Cross
Last day of usage of the numbered Maltese cross
 

[IJ] from London to Newcastle upon Tyne, dated 16 May 1844,
cancelled with a blackNumber 11 Maltese cross

Last day of the numbered Maltese crosses
 

Additional items not in display
 

[QE] from London to Elgin, dated 1 April 1843,
cancelled with a black Number 8 Maltese Cross
Earliest recorded usage of No 8 in Cross and probable first day of usage
Numbers 7 to 12 were entered into the proof book on 1 April 1843
 

[BL] from London to Downpatrick, dated 21 March 1843,
cancelled with a blackLondon No 3 Maltese cross
Very early use of the No 3 Maltese cross (earliest recorded is 16 March 1843)