Overprints Part 2 The First Overprints 
The First Overprints Provisional Government Overprints
Overprinting for the first sheet issues were contracted to two Dublin-based firms. Dollard Printing House overprinted eight low value stamps, see Figure 1 and the three high value stamps, see Figure 2. A second printing firm Alex Thom overprinted the remaining four low values. (Figure 3). The Gaelic overprint for sheet and coil stamps translates to read – “ Provisional Government of Ireland 1922″.
Overprinted stamps by both Dollard and Thom were simultaneously released on the February 17, 1922. The make-up of stamps in rolls, together with the overprinting process was contracted to a third firm – Harrison and Sons Ltd., London. From June 19 to 21, 1922, four low value coil stamps were available to businesses using dispensing machines for affixing stamps for mailing (Figure 4).
The 2d stamps by both Thom and Harrison exist in two major varieties. See the ABC on Overprint Varieties.
Identifiable differences are clearly evident between the overprint styles, adopted by the three contractors.
Major style (typeface) difference between Dollard and the Thom & Harrison overprints.
Shape and form of ‘1922’. (Figure 5)
Harrison overprint style differences, compared with Thom. (Figure 6)
a) Typeface narrower in profile.
b) “R” of “Rialtas” over “Se” of “Sealadac”.
c) Longer tail of ‘i’ in ‘Rialtas’.
d) Overprint lines 1, 2 & 4 wider by 0.5mm and overall height plus 1mm.