Postgebiet Ober Ost Michel Catalog

In Michel catalog under this issue there is this list of prices of pieces where the top margin is attached. What are the numbers 3'7'3 and 2'9'2?
The list at the bottom is for stamps with left or right margin attached?
Thank you!

I see your catalogue has a lot more detail than my old 1999 edition!

The 2,9,2 reference is to the appearance of the vertical lines in the top margin.

In this case there are from left to right: 2 long lines then 9 short lines (above the column value) then another two long lines.

Similarly, 3,7,3 refers to three long lines, 7 short lines and 3 long lines.

There are picture of these in different issues in the Deutches Reich section of the catalogue.

I can show examples from similar issues when I get home later.

They refer to the number of lines on top, the number of long and short lines

Example stamp in bottom left corner would be a 2"9"2.





The bottom part is for stamps wide side margin with perforationin the margin.

These are varieties of rotary press printings. With the flat plate printings, there are no vertical lines.