K&E 4053-3 10" Polyphase Mannheim 1914-1915
Metal Cursor Blocks
These scans are from the collection of Clark McCoy
The cursor blocks on this specimen are marked "PAT. APPL FOR" on the back and "KEUFFEL & ESSER CO NEW YORK" on the edge.
The production lot number for this rule is 548.
Back side of slide