Drawing of escapements for clocks

Made:
1851
maker:
Roberts, Richard

Shows 'Detached crank-escapement', 'Detached pin wheel escapement', and one other. Bears name 'Richd. Roberts, Patentee, Globe Works, Manchester'. Relates to patent 12,207 of July 1848?

Details

Extent:
500
745
Identifier:
MSL/0171