WET/DRY PRINTINGS




Until late 1924 Canadian stamps were printed using what is called the 'WET' process. The stamps were first printed on sheets of paper that had been dampened. After the printed sheets had dried they were gummed and perforated.


Beginning in late 1922 a new 'DRY' process was used. The sheets of paper were no longer dampened and the gum was applied before the printing took place.


Since this changeover took place during the Admiral era it is useful to examine which stamps were printed using which process.



Many collectors are uncertain on how to tell the two types of printings apart. Some try to use the gum on mint stamps since having the gum in place on the sheets during the printing process left a faint embossing on the gum for dry printing. This method is difficult and of course impossible for used stamps. A simple and foolproof method of distinguishing WET from DRY printing is to compare the width of the stamps. Since the paper was damp there was always shrinkage in the direction of the paper grain for wet printings. Since the paper used for the Admirals always had a vertical grain(see 'squat' printing below) it can safely be assumed that all stamps printed using the WET process are narrower than those done with the DRY process.


A collector can choose a representative WET printing such as the 2c CARMINE and a DRY one such as the 10c BROWN. Any other stamp can then be compared to these two examples and it will be immediately obvious whether it is wet or dry.


The following image shows a 2c Carmine superimposed on a 10c Brown


Note the diference in the width of the stamps as measured between the outer frame lines.





A TABLE SHOWING WET AND DRY PRINTING BY VALUE AND PLATE NUMBER


VALUE WET PRINTINGS
BOTH
DRY PRINTINGS
-------- --------------------
-------
--------------------
1c Green Plates 1-170
1c Yellow Plates 169-182 Plates 183-199
2c Carmine Plates 1-160
2c Green Plates 159-169 Plates 170-194 Plates 195-229
3c Brown Plates 1-117 Plates 118-120
3c Carmine Plates 115-176
4c Bistre Plates 1-4 Plates 5-7
5c Blue Plates 1-14
5c Violet Plates 15-22 Plates 23-25
7c Bistre Plates 1-6
7c Red Brown Plates 7-8
8c Blue Plates 1-3
10c Plum Plates 1-12
10c Blue Plates 13-20 Plates 21-22
10c Brown Plates 21-25
20c Olive Plates 1-5 Plates 6-7 Plates 8-9
50c Grey Plates 1-3 Plate 4
1$ Orange Plate 1
1c Green War Tax Plates 1-18
2c Carmine War Tax Plates 1-10
2+1c Carmine War Tax Plates 1-16
2+1c Brown War Tax Plates 1-2,15-60




First glance at the above table would seem to indicate that there was indeed a point at which the printing method shifted from 'WET' to 'DRY'. For many values one plate was printed 'WET' and the next in sequence was printed 'DRY'. When there is an overlap only 1 or 2 plates are printed using both methods. This suggests that there was indeed a time when the printing method in general use was switched. However the 2c Green stands out as an exception. Plate 170 is the first plate that I have identified as being printed using the 'DRY' method. This plate was in use almost 2 years before the general changeover date of late 1924. Given the number of plates used for both printings it would seem logical to suppose that the 2c Green was used as the test for the process.






The exact duration of this testing period is of course open to debate since it depends on finding the earliest possible 'DRY' printing. I include here a list of 2c Green plates in the range 170-194 that I have found along with their printing method.


PLATE
PRINTING METHOD
170
Dry
171
Wet
172
Wet
173
Wet
174
Wet
175
Wet
176
Wet
178
179
Wet
180
Wet
181
182
Wet,Dry
183
Dry
184
Dry
185
Wet
186
Wet
187
188
Wet
189
Wet
190
Dry
191
Dry
192
Dry
193
Wet,Dry
194
Wet




It is difficult to complete this study because of the rarity of plate pieces from this period. The 2c Green is actually very rare except for pieces from plate number 220 on.


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