As a sphere with ridged stitching, baseball aerodynamics contain odd movement potential when spun or floated properly. Modern hurlers work at the seams and cover, trying to create enough wrinkle or imbalance to add an extra dip, ideally with fingers only and not "additives" like spit or vaseline. Enough guys get caught to remind us that cheating persists, but it's not something you see very often.
Best I can tell, Tom Daniels was a collector or printer who financed this direct-to-collectors set with Grimes' personal assistance (and photos). HOFer Burleigh personally signed at least one card in each set, making autographed versions relatively easy to find. Legendary Auctions even sold a completed version for just under $200 in 2005.
A 40 year-old Grimes played part of his final season with the Yankees in 1934, just beating out Babe Ruth for oldest team member. They both moved on in 1935, Ruth to Boston's Braves in search of a managing opportunity, and Burleigh to retirement. (He ultimately got the chance to manage that Babe never landed, helming the Brooklyn Dodgers 1937-38.)
Value: Cards cost a dollar or two, with autographed versions running $10-20.
Fakes / reprints: Haven't seen any in the marketplace.