Potter's test piece fragment ... Jeff Vanderpool ... Well L 11:1. Horizontal (normal) ... 20 Apr 2021
Potter's Test Piece Fragment ... AMS Horizontal (normal)
Potter's Test Pieces ... AMS Rotate 90 CW
Potters' debris test pieces wasters ... Anne Hooton ... Drafting Film Drafting Ink
Potter's Test Piece Fragment. Well ... ΩΔ-5 851, 852 P 32365 P 32366 ΩΔ 483 P 32367 L 11:1 P 32365 P 32366 P 32367 ... 3-4 July 1946