Locking; being an elementary treatise on the mechanisms in interlocking lever machines by which the movements of the levers are restricted to certain predetermined ways, rendering it impossible to operate conflicting switches and signals on railways
- publisher: East Orange, N.J., F.C. Lavarack
- creator: Lavarack, Frederick Charles, 1883-
- contributor: University of Michigan
- mediatype: texts
- years: 1907
- pages: 173
- language: English
- lccn: 07040015
- download: pdf file
