An unusual book, but may hold interest for those interested in the Hoosac Tunnel. "Tri-nitro-glycerin as applied in the Hoosac Tunnel Submarine Blasting", by George M. Mowbray. Here at this link:
https://www.gutenberg.org/ebooks/65791 Also unusual in that several of the photos in this book are actually stereo pairs!
https://www.gutenberg.org/ebooks/65791 Also unusual in that several of the photos in this book are actually stereo pairs!