Description – PM type B4 group (JC-MN) Bombay urban post offices group, with various subtypes, either singular or in duplex form (listed below). Variations B4a to B4g are found only on De La Rue printing stamps1855 onwards, a small very number in blue or violet ink. 

This particular B4 singular type diamond of 12 thicker bars (sometimes 10 or 11) with thick Roman numeral 1. These are encountered on both Lithographic 1854-55 and early DLR issues without watermark – Common except a few late examples found post 1865 watermarked issues.

PM subtype B4a – Duplex with narrower tall diamond of 11 or 12 bars ascending right to left – Considered common. Some examples exist bars ascending left to right – Considered scarce. The left side of this type have considerable variations in design, including double-ringed circular, single, or open-topped circulars – only the latter type illustrated by Cooper.

Examples in this collection date from 20th March 1862 to September 1868

PM subtype B4b – (JC) type 4i (RF-MN) Duplex with square-like diamond of fine bars within circle. Again variations existed on left side circular – Common.

PM subtype B4c – Duplex with numeral ‘1’ double-lined figure, and left side tends to be double-ringed circle ‘India Paid’ at foot. This double-lined figure one should not be confused with type B4e duplex rising left to right with slenderer hollowed figure) - Its usage seems to date on covers between 1868-70, and is possibly a bit scarcer than Cooper suggests?! 

Various examples in this collection date from 23rd September 1868 to 21st January 1870

PM subtype B4d – (JC) type 4k (RF-MN) Duplex with smaller diamond of finer close together lines numbering between 13-16 ascending left to right with fine or thin distinct horizontal bars plus extended well-defined serifs to numeral. Very similar to left ascending type B4a PM - Scarce 

Various examples in this collection (allocated B4a?) date from 4th March 1866 to 15th Sept 1869

PM subtype B4e – (JC) type 4j (RF-MN) Duplex similar to subtype B4d except distinct numeral ‘1’ hollow, or not shaded or hollow within. Scarce 

Various examples in this collection date from 24th July 1866 to 27th July 1868

PM subtype B4f – (JC) type 4m (RF-MN) Singular small square-like diamond with 10 fine close together lines ascending right to left often found struck on stamps multiple times.

Various examples in this collection date from 1st May 1874 – 1st August 1879

PM subtype B4G – (JC) type 4n (RF-MN) Duplex with right side small outlined square-like diamond of 10 or 11 lines, and numeral inset between 1-10 correlating with various City sun-post offices, not all known. This collection contained a good number of examples. Very scarce but probably rare complete on cover. 

These number of examples add more to Martins brief notes (Numbers in Early Indian Cancellations 1855-1884 Martin D.R., Col: pp140: 1970 p.110) when only 2 of 10 are noted 2 Mazagaon, and 10 Collaba dating from 1867 to 1868

Probably Martins recorded instances are from the actual various examples in this important collection date from 1st July 1867 (few examples are 1857 but as on post 1865 amazingly show a decade year error!! See shop cover!) to 7th August 1869.