In one of the more incredible finds, we were able to discover the D.L. Clark Company had sent the designer of these sports-themed box bottoms (cards) a letter saying that company executives loved the designs. While not in the collection, an image of that letter is included below. The baseball series would commence in the summer of 1953. If they stayed stayed on schedule, the basketball set would start late that same year and continue into 1954. The most incredible part of this find is the entire series of basketball artist prototypes (1-16) for this set. The are the exact same size as the box bottom (10 1/2" x 7"). They are black and white with a glossy front. Definitely, these are one-of-a-kind, and together with the letter, help explain the very beginnings of this set.
D.L. Clark Company