1¢ Bluish green
Subject: George Washington
Printing Method: Rotary Press (see below)
Perforations: 10 x 11
Watermark: None
Scott #: 542
Issued: May 26th, 1920
Used
50¢ - $1.25
No postmark with gum (MH)
$4- $5
Full perfect gum, no postmark
no trace of stamp hinge mark (MNH)
$10 - $20
#542 was issued with the following plate #'s
Number only
10151-52
10436-37, 39
10509-10
10635
11738-39
12467-68
First day of issue cover, May 26th, 1920
This stamp was one of the experimental issues. The sheets were made just for this perforation, hence no straight edges. They were perforated twice, once on a bar perforator and once on a wheel perforator. As a consequence, centering is poor.
A complete pane of #542 (100 stamps), there were four panes to a sheet of 400 stamps. Instead of guide lines separating the panes, margins were used, the vertical inside margin can come with or without a small hyphen in the margin.
As the curved plates of the Rotary press made the stamps slightly larger it is relatively easy to discern which stamp is flat plate and which is a rotary press stamp. First select any perf Washington Franklin stamp or the first issue Washington Franklin 1 cent or 2 cent. These are the stamps with the numbers one and two spelt out, instead of numbers being displayed. I chose the latter alternative as shown in the first image above.
Then cut out squares at each corner. As shown in the second image above. Placing the stamp you wish to test under your cut out stamp you can see if the frame lines match. If, as in the last image shown above the frame lines are outside the top stamp in either the top, bottom or sides then you have a rotary stamp. If the lines are in the same place, as shown in the third image, you have a flat plate stamp.
This test works with any value stamp.
The image above is a perfect example of the reverse of a flat plate stamp. The flecks of carmine ink on the reverse can be found on flat plate and are very rare on rotary press stamps. The cause of the flecks of carmine ink is that during the flat plate process the sheets were placed on top of each other before the ink had a chance to dry properly.