Files

Articles -Presentations-Histories-Biographies (26 files)

General Files - Patents (2 files)

GTD-Helix (2 files)

GTD-Leads-and-Angles-Newsletters-1942-1943 (15 files)

GTD-Magazine-ads-from-paintings (0 files)

Historic Corridor (5 files)

History of Mill Site & Dams (3 files)

Sound Files (0 files)

Tool Catalog PDF (2 files)