(Note: These map images are very large (2.1MB each).
I tried reducing them but the loss of detail defeated the purpose.)
Use the [Ctl]+ and [Ctl]- keys to zoom in and out on the image pages.
The quadrants overlap substantially; the entire map covers Reading, upper Wakefield, North Reading, Lynnfield Center, Andover, some of North Andover, and some of Peabody.
When these maps were produced, Route 128 around Greater Boston was a new addition to the landscape. The interstate highway system did not exist, and only a few semi-urban parkways had been built – in and around New York City, in Southern Connecticut and along the rivers in Boston.