Burlington Northern Railroad. Signal Aspects and Indications. Brochure provides color illustrations of various Automatic Block, CTC, and Interlocking Signal Systems as well as Train Order Signals and those that are not part of Automatic Block, CTC, and Interlocking Systems. February 1, 1977. 5 panels. 3 3/4" x 6 1/2'. Shipping via USPS First Class Mail. I will consolidate orders, if requested, to save on shipping costs.
