A History of Engineering & Science in the Bell System The Early Years 1875-1929

[Sargeguy]

A History of Engineering & Science in the Bell System The Early Years 1875-1929 was published by Bell Laboratories in 1975 to commemorate the 100th Anniversary of the Telephone.  It traces the technical developments that enabled the expansion of the Bell System through the early years.  There is some of information from the "Dark Ages" that isn't generally accessible elsewhere, as well as some curious gaps (the 143AW transmitter is omitted).  There are plenty of ex-library copies around and they are relatively cheap.

[Weco355aman]

There is two versions of the the early years and the 2ND book 1930 and later.
Both are very good books. The 2ND book was more into the switching and network.