Limits of closure???
William, the method used with a solar compass would follow along a latitudinal arc as opposed to a straight line. Offsets would not be determined, per se. They may not have used precise methods, but to retrace their work you need to take into account the bearing line they travelled along when using a solar compass.
When traversing with a transit, they have a "red book" to determine the change in bearing on a line from one end to the other. A forward bearing on a line and a back-bearing on a line.
Limits of closure???
First, the limits of closure was something like you posted, but we were within the 1:5000 error of closure most of the time. Our Special Instructions gave the limit of closure to be attained.
And plumb bobs were not used that much. When I was chaining, I was rear chainman and usually down on my knees holding the chain with chain grips and directly over the chaining pin that was dropped by the front chairman.
Curvature came from the instrument used, either the solar transit, or a transit line with bending bearings.
Keith