Pre- Lateral
Type 1 solid brass adjuster, no name on it, Banjo type spring on Lever cap
Type 2 solid brass adjuster, Bailey & Patent on it, rectangular type spring on Lever cap
Type 3 two piece frog
Type 4 hollowed(recessed) adjuster with “BAILEY’S PATENT”…2 patents on Adjuster

Added Lateral
Type 5 First lateral (L shaped) Number now cast on toe in front of knob
Type 6 Low front knob (No longer beaded), 3 patents on the Lateral Adjuster
Type 7 Low front knob (No longer beaded), 3 patents on the Lateral Adjuster AND "S" cast in bed
Type 8 Low front knob (No longer beaded), 1 patents on the Lateral Adjuster AND "B" cast in bed
Type 9 Two patents behind the frog and NO frog adjustment screw 
Type 10 2 patents behind the frog and a small depth adjuster
Type 11 3 patents behind the frog and a small depth adjuster with a low knob
Type 12 3 patents behind the frog and a large depth adjuster with a high knob
Type 13 A high knob and one patent date AND without the raised ring for the knob, is probably a
Type 14 1 patent date behind frog. MADE IN U.S.A. cast at toe, raised ring for knob
Type 15 MADE IN U.S.A. behind frog, BAILEY cast behind knob, no Raised, broad, flat rib cast at toe and heel
Type 16 A Raised, broad, flat rib cast at toe and heel, with the New Ogee shaped frog ("Stanley NOT stamped vertically like the type 19)and non of the type 17 or 18 features
Type 17 steel or rubber depth adjuster, with or without frog adjustment screw, Painted knob & tote
Type 18 diagonal knurling on the cutter adjustment knob
Type 19 "STANLEY” written vertically On Lateral Adjuster


https://www.timetestedtools.net/2016/01/27/stanley-bench-plane-typing/