Irish provisional overprints

In December 1921, Ireland gained independence from Great Britain with the exception of Northern Ireland.

Contemporary British stamps were overprinted in insular script Rialtar Sealadaċ na hÉirann 1922 (roughly). There are several printings to deal with with these issues. 
 * The first issue was the Dollard printing in black (sometimes gray-black), the overprint measuring 15x17.5mm. "1922" is styled with "I" instead of a "1". Four values also commonly exist overprinted in red.
 * Seahorse shilling values were similarly overprinted, 21.5x14mm in size, though occasionally measuring 21x14mm. This issue can be distinguished from later issues with a clear space between "h" and "é" in "h é irann".
 * Four values were also overprinted by Alex Thom & Co. (Thom I printing), overprints measuring 14.5x16mm.
 * Dollard once again overprinted Seahorses, now in blue black ink and with "h" and "é" very closely space. See "Notes" below.
 * Harrison & Sons also overprinted four coil stamps measuring 15.25x17mm in shiny black ink. Coils and the Harrison prints are additional detectable by parallel perfs (vertically or horizontally) being trimmed absolutely straight, similar to how British booklet panes are trimmed.
 * Thom produced more overprints in a new setting measuring 14.5x16mm (Thom II). These were in done in blue black ink.
 * Thom then overprinted in yet another setting measuring 15.75x16mm (Thom III). These were also done in blue black ink.
 * These were soon replaced by the Saorstát é irann 1922 overprints. See: '''Irish Free State overprints

