Telegraph central office set TC-3 and switchboard BD-100 - USA Voorschrift, Technical Manual, 11-358 Principles of long distance telephone and telegraph transmission - USA Voorschrift, Technical Manual, 11-475 Seacoast artillery : service of the piece 3 -inch rapid-fire gun : (barbette carriage) - USA Coast Artillery Field Manual, FM 4-90 Elementary map and aerial photograph reading - USA Voorschrift, Basic Field Manual, 21-25 Basic photography - USA Voorschrift, Technical Manual, 1-219 Aerial photography - USA Voorschrift, Technical Manual, 1-220 Elementry map and aerial photography reading - USA Voorschrift, Field Manual Advanced map and aerial photograph reading - USA Voorschrift, Field Manual, 21-26 Advanced map and aerial photograph reading - USA Basic Field Manual, FM 21-26 Photographic laboratories : organization and operation in service commands, departments and posts - USA Voorschrift, Technical Manual, 11-409 Photographic laboratories : organization and operation in class I and II installations - USA Voorschrift, Technical Manual, 11-409 Thermographs ML-77 and ML-277 - USA Voorschrift, Technical Manual, 11-426