Sirmoor had a relatively short philatelic life, 1878 to 1902, but it was quite action-packed.
The first issue was one of the less adventurous stamp designs:
SG 1-2
For some unaccountable reason, these stamps proved popular enough with our stamp-collecting ancestors to prompt Sirmoor to order a reprint. That caused a problem, though: stocks were exhausted and the original lithographic stones had been wiped and reused. In its innocence, the Sirmoor Post Office sent the printers
illustrations of the stamps, complete with simulated perforations. The printers executed the order faithfully, complete with 'perforations':
SG 3-4
I show two types of cancellation. The first seems to have been a CTO; the second is a genuine usage (and quite a late date. These stamps were probably originally intended mainly for collectors, but demand being lower than expected, they were put to their proper use.)
In 1885, Sirmoor decided to do things properly, and had a set of four values lithographed by Waterlow:
SG 5-9
These stamps are much more traditional philatelic fare. Plenty of shades, and two different types of each the two low values, varying in the size and position of the white dots before and after the values.
A word of caution on condition: It's relatively uncommon to find these stamps in fine condition. Pulled and short perforations and the gum problems common to late Victorian stamps (missing, thinned, and once having been glued to an album page) are almost the norm.
Sirmoor had quite got into the swing of soaking the collector by this stage. In 1894, they released a long thematic set:
SG 22-9
recess printed by Waterlow. Gibbons notes that these are 'perf 12 to 15 and compounds'. I've never taken the set seriously enough to see what perforations I could find in it, but
you might like to take on the challenge, gentle reader.
Take care with the 1 Rupee value. It's often found oxidized.
In 1899, Sirmoor followed up with some more high values, again recess printed by Waterlow:
Treat any value above 2 Annas used with the greatest suspicion. If it's obviously CTO, and you're happy with that, OK; if it purports to be postally used, proceed at your own peril. The actual postal usage of the high values must have been tiny.
Sirmoor also overprinted SG 5-9 with On S(irmoor) S(tate) S(ervice), for government use. (Note that they didn't bother with any higher values!) And this is where Sirmoor
really began to get into its stride. Gibbons distinguish nine machine printed and another nine handstamped types of overprint, and a couple of very rare combinations of both. Here are a few examples:
The last (2 Annas) stamp is an example of the handstamps; each element was handstamped separately. Of course, errors occurred:
SG 60e, SG 65b and SG 92a
In the first stamp, the second 'S' is inverted and the full stop is raised. The second is a straightforward inverted overprint. In the last stamp, only the word 'On' was printed - the 'S' must have been mislaid; this 'error' is actually more common than the complete handstamp.
Some other stamps were also overprinted On S S S. The low values of the elephant set turn up from time to time. Apparently, these were never put into official use.
One more quirk of Sirmoor is worth noting. It was a small state and its stamps were only valid for postage within the State; however, it
was conveniently close to Simla, the Summer capital of India at the time, so could be visited by stamp collectors fairly easily. Nevertheless, used copies of Sirmoor are usually plentiful, and often cheaper than mint. This was because the Sirmoor postmen were under instructions to recover all used postage stamps from the recipients of letters. Understandably, covers are extremely rare. (A commercial cover with a pair of SG 6 and a single of SG 9a - the 3 Pies orange and 2 Annas Carmine - went for over £2000 in 2006, against a catalogue value for the used stamps
off cover of £3.60. Now who wants to soak stamps off cover ...

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