Prior to WWII, the BOWMAN GUM Company marketed their Sports and Non-Sports cards (1938 - 1942) with the Trademark....
GUM, Inc.

When Bowman introduced their first BB card set after WWII, they continued the "PLAY BALL" Trademark on their wax-pack wrapper. These 1948 wrappers are very rare.
1948 Bowman 1-cent wrapper

..
The printing of the 1948 BOWMAN set is very interesting.....the printer took their 36-card production sheet and produced a 48-card set. In their 1st press runs
they printed cards #1 - 36. Then, in their later press runs they modified their printing plates by replacing 12 cards in the first group of 36 with cards #37 - 48.
The 36-card uncut sheet shown here represents the later press runs. Cards #37 - 48 are interspersed among the lower number cards. Therefore, this process
created Double-Prints of 24 low numbers....Single-Prints of 12 low numbers....and, another set of Single-Prints of the 12 high numbers.
TED Z
.