General outline history.
Completed 27 May 1853.
Imprimatur registered 20 July 1853.
Put to press 19 August 1853.
EKU (imperforate) 27 September 1853.
Plate repair (all 240 units?) 23 March 1854.
EKU (perforated) 28 April 1854.
Withdrawn from press end of August 1854 (Statham).
Defaced 8 February 1855.
Notes
Estimated printing of 91,000. Statham estimates 44k/47k split between imperf and perf. Folkard points out that the imperf are relatively scarce, whilst the perforated examples are plentiful. Some late states have been seen on imperforated examples, though these are scarce.
This plate was almost certainly one of the unhardened plates.
Some positions are known in three states. (When was the second repair and how many positions, on a hard or soft plate?) See grid below.
173 can be found with the following perforation varieties:
S&S 2.2 ( Early Feb 1854?)
S&S 3 (Early April 1854?)
S&S 4.1/2/4 (End April 1854?)
S&S 5 (Mid-Late Aug 1854?)
Statham pg 2021 on.
Folkard GBJ vol 19, 50-54, 74-83 and Vol 20 10-13, 28-31, 54-57, 68-70
Simpson & Sargent.
Later states study