International Radiotelegraphic Convention
List of Abbreviations to Be Used Radio Communication
Audel's Handy Book of Practical Electricity

My grandfather, Roland (my middle name) Somers, on my mother's side was a residential (aka house) builder. He owned and operated a small (2-3 employees) business in Mayo, Maryland in the middle of the last century. Being his only grandson, I got what survived of his books like this Audel's Handy Book of Practical Electricity, c1942, by Theo. udel & Co. Publishers. I also have a couple of his carpentry and hand tool books of the era. 

The scanned page below is titled, "List of Abbreviations to Be Used Radio Communication," as dictated by the International Radiotelegraphic Convention (IRC). Amateur radio operators will recognize the list as being a collection of the familiar "Q" Signals, although stated in sometimes archaic prose; e.g., QRN = "Are the atmospherics strong?" and QSB = "Is my spark bad?"

The book is filled with good information on motors and generators, switching and control circuits, electrical theory, and other stuff still valid today. The section on knob-and-tube wiring can probably be skipped. I used to see that stuff in turn-of-the-20th century houses when working as an electrician back in the 1970s.

International Radiotelegraphic Convention List of Abbreviations to be Used Radio Communication