NOTE:
Although all of these digitized articles are 60 or more years old, and likely have minimal commercial value today, the reader should bear in mind that material dated after 1923 remains under copyright by Simmons-Boardman Publishing.
These articles and the information contained therein may be freely reproduced or used in printed or electronic form for non-commercial or educational purposes, provided the copyright holder and original author (if known) are acknowledged, and provided that such publication also refers readers to the original document on this site.
Simply making interesting material available to those who share my interest in the railway signal systems of the past has been my sole objective in this long project.
1943 | Centralized Traffic Control Installed On 64.6 Miles of the Seaboard 7.1 MB |
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1944 | CTC On 185 Miles on Canadian National 12.3 MB |
1944 | CTC Speeds Ore Traffic On the DM&IR 4.6 MB |
1940 | Entering the Main Line 1.3 MB |
1944 | Signals Direct Trains at Junction On the Denver & Rio Grande Western and the Denver & Salt Lake 2.8 MB |
1958 | C&O Has Good Ideas in CTC 2.5 MB |
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1955 | CTC Saves Time for Freights On 135 Miles of Single Track 4.0 MB |
1950 | Neon Lighting For Crossing Gate Arms 3.1 MB |
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1935 | Safety of High Speed Trains 5.2 MB |
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1949 | 625 Miles of CTC in one Stretch 7.9 MB |
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1937 | CTC On the Denver & Rio Grande Western 8.0 MB |
1954 | Electric Interlocking on the Rio Grande 3.4 MB |
1943 | Union Pacific Installs CTC on 175 Miles of Single Track 13.2 MB |
1954 | CTC Improves Train Operation 3.3 MB |
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1948 | New Signaling In Texas on Missouri Pacific Lines 1.8 MB |
1947 | Railroads Request Relief from the ICC Signal Order 465.0 KB |
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1947 | ICC Holds Signal Hearing 507.5 KB |
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1944 | Santa Fe Installs CTC on 115.6 Miles Los Angeles to San Diego 7.2 MB |
1915 | Electro-Pneumatic Plant at San Francisco 2.4 MB |
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1947 | ICC Holds Signal Hearing 507.5 KB |
1937 | Illumination as a Type of Crossing Protection 3.0 MB |
1935 | Safety of High Speed Trains 5.2 MB |
1939 | San Francisco-Oakland Bay Bridge Interlocking Plants 9.4 MB |
1939 | San Francisco-Oakland Bay Bridge Signaling and Interlocking 7.9 MB |
1935 | Depression Operation of Interlocking 2.6 MB |
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1939 | Trains Directed by Signal Indication at San Jose, California 4.1 MB |
1949 | New Automatic Block on the Katy 4.7 MB |
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1946 | Drawbridge Interlocking on the New York Central 3.1 MB |
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1947 | Railroads Request Relief from the ICC Signal Order 465.0 KB |
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1929 | Frisco Installs Semaphores with Color-Light Indication 665.1 KB |
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1943 | Centralized Traffic Control Installed on 39 Miles of the Burlington 6.1 MB |
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1927 | Comparative Maintenance Costs of Signaling on the CM&StP 2.9 MB |
1947 | More CTC on the Burlington 2.0 MB |
1947 | Annual Review and Outlook 425.1 KB |
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1943 | Centralized Traffic Control Installed On 64.6 Miles of the Seaboard 7.1 MB |
1926 | Signal Business Is Good Especially For Single Track 382.3 KB |
1944 | Track Circuits on Passing Tracks in CTC Territory 941.8 KB |
1915 | Electric Train Staff Installation 3.3 MB |
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1920 | Largest Saxby & Farmer Machine in the United States 1.6 MB |
1936 | T. George Stiles Rounds Out 60 Years of Signaling 2.5 MB |
1942 | Automatic Signal Program on the Illinois Central 4.6 MB |
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1940 | Make-Up-Time Chart 813.1 KB |
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1947 | Hoosac Tunnel Interlocking and CTC 1.7 MB |
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1933 | Remote Control on Soo Line 2.7 MB |
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1937 | Changes on the New York Central Lines 2.3 MB |
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1927 | NYC First to Install Complete Train Dispatching System 8.0 MB |
1915 | Rule 55 and the Gretna Accident 1.8 MB |
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1920 | The New Electrification on the St. Paul 485.4 KB |
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1934 | CTC Replaces Staff on GTW 2.6 MB |
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1948 | CTC Keeps ‘em Rollin’ on C&EI 2.1 MB |
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1911 | Signaling on the Illinois Traction System 1.5 MB |
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1924 | Results of Train Control Test on Pennsylvania 3.1 MB |
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1940 | Controller Adjuster 1.3 MB |
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1911 | Summary of Recent Progress in Signaling 4.4 MB |
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1919 | Block Signaling Practice on a British Railway (Part 3) 327.2 KB |
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1953 | Route Lever Interlocking on Rock Island 6.5 MB |
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1936 | Reading Installs Unique Crossing Protection 9.5 MB |
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1913 | New Block Signaling on the North-Western 1.8 MB |
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1937 | Personal: C&NW 1.3 MB |
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1926 | Train Control Progress in 1925 3.1 MB |
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1950 | CTC on the Reading 6.6 MB |
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1911 | Relay Shipping Case 1.1 MB |
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1922 | Signal Construction on the Santa Fe 797.6 KB |
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1926 | Train Control Progress in 1925 3.1 MB |
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1947 | Railroads Request Relief from the ICC Signal Order 465.0 KB |
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1956 | Main Track Leaving Signal 2.2 MB |
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1941 | Automatics Installed on the Wabash 4.0 MB |
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1928 | Saco Lever Circuit Controller 735.1 KB |
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1954 | Fewer ICC Signal Applications 1.7 MB |
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1936 | Maintainers' Blueprint Plans 4.2 MB |
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1949 | A Century of Signal Glass Developments 4.2 MB |
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1935 | Multiple Aspect Signaling 3.3 MB |
1935 | Purple Signal Glasses 3.6 MB |
1935 | Purple Signal Glasses 3.3 MB |
1937 | Selection of Colors for Signal Lights 1.3 MB |
1937 | Prepare for Construction 1.2 MB |
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1937 | Signaling Construction Methods 2.6 MB |
1950 | Continued Improvement In Signal Performance 1.3 MB |
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1946 | Improved Signal Performance 446.8 KB |
1937 | Flag and Torpedo Containers 903.1 KB |
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1949 | A Century of Signal Glass Developments 4.2 MB |
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1929 | Factors to be Considered in Selecting Glass for Signal Lenses 4.2 MB |
1915 | Glass Standardization for Railway Signaling 1.0 MB |
1939 | Action at Approach Signal 964.5 KB |
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1935 | Collision on the T&P 2.0 MB |
1936 | Demands for Modern Signaling 12.1 MB |
1936 | Double-Caution Signaling 3.4 MB |
1943 | Instructions in Signal Aspects and Indications to New Employees 5.6 MB |
1911 | Letters to the Editor: Uniform Signaling: A reply to Mr. Rudd 1.8 MB |
1911 | Railway Signal Association Convention: Committee I: Signaling Practice 3.8 MB |
1950 | Signaling and Rules 1.4 MB |
1911 | Signaling Practice on Steam Railways 5.5 MB |
1940 | Single-Track Signaling 2.5 MB |
1937 | Signal Inspection Bill Passed by Congress 3.4 MB |
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1911 | Results of Inspections Made by the Block Signal and Train Control Board 2.8 MB |
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1939 | The Signaling Regulations 907.9 KB |
1937 | Instructing Enginemen on Signal Indications 2.7 MB |
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1935 | Checking Signal Lamps 3.3 MB |
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1935 | Night Intensity of Signal Lamps 2.6 MB |
1937 | Replacement and Life of Lamps 3.0 MB |
1956 | Signal Lamp Test 1.4 MB |
1956 | Signal Lamp Test 950.0 KB |
1949 | A Century of Signal Glass Developments 4.2 MB |
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1937 | Electric Signal Lights in Austria 1.2 MB |
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1935 | Night Check of Signal Lights 1.2 MB |
1935 | Night Intensity of Signal Lamps 2.1 MB |
1937 | Broken Rails 1.1 MB |
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1935 | Maintainers' Tool Houses 2.2 MB |
1935 | Obsolescence in Signaling 3.4 MB |
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1950 | Continued Improvement In Signal Performance 1.3 MB |
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1956 | Photography 1.5 MB |
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1939 | A Signal Shopping Policy 965.3 KB |
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1939 | A Signal Shopping Policy 965.3 KB |
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1956 | Three Signal Shops into One 7.0 MB |
1935 | A Problem in Spacing Signals for Higher Train Speeds 1.6 MB |
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1935 | Braking Distance with Signals 2.4 MB |
1935 | Multiple Aspect Signaling 3.3 MB |
1935 | New Signaling on the Route of the C&NW "400" 9.6 MB |
1935 | Respacing Automatics on the Pennsylvania 1.8 MB |
1935 | Safety of High Speed Trains 5.2 MB |
1935 | Signaling for Higher Train Speeds 3.0 MB |
1935 | Stopping Distance and Signal Spacing 1.8 MB |
1940 | Pennsylvania Testing Procedure 16.6 MB |
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1940 | Pennsylvania Testing Procedure (Part II) 8.6 MB |
1940 | Pennsylvania Testing Procedure (Part III) 8.9 MB |
1935 | Signal Transformers 2.2 MB |
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1911 | An Interesting Case of Trouble 776.2 KB |
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1937 | Unusual Signal Trouble 1.2 MB |
1939 | Unusual Signal Trouble 835.4 KB |
1937 | Unusual Signaling Trouble 2.2 MB |
1937 | Gauntlet Signals on the B&LE 7.1 MB |
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1933 | Modern Signaling in Soviet Russia 3.3 MB |
1943 | Railway Signaling in North Africa 3.5 MB |
1935 | Remote Control on the Seaboard 5.4 MB |
1935 | Signaling at Spring Switches 2.6 MB |
1938 | Signaling at Spring Switches 930.3 KB |
1952 | Soo Line Completes Signaling on 260 Miles of Single Track 737.7 KB |
1950 | Spring Switch Signaling 2.5 MB |
1912 | The New York, Westchester & Boston Railway (1912-08) 4.1 MB |
1912 | The New York, Westchester & Boston Railway (1912-10) 4.7 MB |
1912 | The New York, Westchester & Boston Railway (1912-12) 4.8 MB |
1945 | The Post-War Importance of Signaling 522.0 KB |
1927 | The Public Is Interested in Signaling 444.4 KB |
1928 | Why Markers for Automatic Signals? 494.6 KB |
1911 | A Summary of Signaling Practice 3.6 MB |
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1911 | Railway Signal Association Convention: Committee I: Signaling Practice 3.8 MB |
1937 | Report of Committee X – Signaling Practice 2.9 MB |
1911 | Signaling Practice on Steam Railways 5.5 MB |
1956 | CTC Signs 1.8 MB |
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1937 | Automatic Plant Replaces Mechanical Interlocking 1.3 MB |
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1936 | What Is the Capacity of a Single-Track Line? 2.0 MB |
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1956 | Double to Single Track With CTC 7.4 MB |
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1947 | Annual Review and Outlook 425.1 KB |
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1946 | CTC on 107 Miles of Single Track on the Louisville & Nashville 5.2 MB |
1947 | Railroads Request Relief from the ICC Signal Order 465.0 KB |
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1947 | 107 Miles of CTC on the N&W 2.3 MB |
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1936 | Slide Detector Fences 4.3 MB |
1935 | "Chattering" Slot Arms 2.3 MB |
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1950 | Temporary Change of Signal Controls 2.2 MB |
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1940 | Plug Couplers for Relays and Signals 1.3 MB |
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1956 | Snow Melters 2.6 MB |
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1935 | Snubbing Rectifier for 2A Signal 1.9 MB |
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1935 | Snubbing Relay for Semaphores 1.0 MB |
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1947 | Hoosac Tunnel Interlocking and CTC 1.7 MB |
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1939 | Phantom Indications in Color-Light Signals 2.2 MB |
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1924 | Three Train Control Contracts Let 1.9 MB |
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1922 | Signal Construction on the Santa Fe 797.6 KB |
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1949 | 192 Miles of Automatic Block On Soo Line 6.0 MB |
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1948 | Gates at Three Crossings on Soo Line 1.8 MB |
1941 | Remote Control Installation 2.4 MB |
1933 | Remote Control on Soo Line 2.7 MB |
1952 | Soo Line Completes Signaling on 260 Miles of Single Track 737.7 KB |
1947 | Railroads Request Relief from the ICC Signal Order 465.0 KB |
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1948 | Car Numbers “Grabbed” by Voice Recorder 783.1 KB |
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1939 | Unusual Signal Trouble 835.4 KB |
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1935 | New Signaling on the Boston & Maine 9.9 MB |
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1937 | New Signaling on Pennsylvania 1.0 MB |
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1938 | Pennsylvania Electrification Signaling 5.3 MB |
1915 | Electric Interlockings in Australia 3.9 MB |
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1927 | Chicago South Shore & South Bend Changes Signal Equipment 2.6 MB |
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1930 | New Electric Interlocking 3.2 MB |
1949 | New Space Radio Relay System Adopted by South Shore 4.2 MB |
1935 | New York Central Extends South Bend Interlocking 6.0 MB |
1931 | One Electric Interlocking for Two Drawbridges 3.1 MB |
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1950 | Automatic Block Increases Safety on Paired Trackage 4.6 MB |
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1947 | Railroads Request Relief from the ICC Signal Order 465.0 KB |
1930 | New Type Rail Crossing Uses Turntable Principle 964.5 KB |
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1913 | New Block Signaling on the North-Western 1.8 MB |
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1929 | C. & A. Modernizes Signaling Facilities 2.2 MB |
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1934 | Centralized Traffic Control Installed on the Alton 1.7 MB |
1935 | Remote Control on the Seaboard 5.4 MB |
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1954 | New Orleans Passenger Terminal 4.7 MB |
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1933 | Modern Signaling in Soviet Russia 3.3 MB |
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1950 | New Developments 16.9 MB |
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1944 | CTC Speeds Ore Traffic On the DM&IR 4.6 MB |
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1953 | CTC Keeps Trains Moving on Long Grades 6.3 MB |
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1958 | CTC Handles 15 More Trains 2.2 MB |
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1938 | EJ&E Installs APB Signaling 3.1 MB |
1949 | Yardsticks 947.2 KB |
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1952 | Speed Control Installed on the Long Island 1.3 MB |
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1946 | ICC 50-MPH Signal Hearing 6.9 MB |
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1946 | ICC Signal Hearing 1.3 MB |
1946 | ICC Signaling Investigation 770.4 KB |
1936 | Speed Limits at Automatic Interlocking 3.2 MB |
1937 | Track Layout for CTC 1.2 MB |
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1924 | Three Train Control Contracts Let 1.9 MB |
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1949 | 192 Miles of Automatic Block On Soo Line 6.0 MB |
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1952 | Soo Line Completes Signaling on 260 Miles of Single Track 737.7 KB |
1950 | CTC on the Wabash 2.6 MB |
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1947 | Territories Involved in the ICC Signaling Order 399.0 KB |
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1931 | Chicago & Illinois Midland Installs Electric Interlocking 2.5 MB |
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1950 | Gulf, Mobile & Ohio Protects All Street Crossings in Springfield 2.6 MB |
1945 | Manual Block-Remote Control Developed On the Wabash 5.7 MB |
1950 | OSing Device 1.4 MB |
1935 | Semi-Automatic Interlocking at a Crossing on the Alton 4.4 MB |
1915 | Extension of New Haven signals 684.8 KB |
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1950 | Frisco Moves CTC Machines Without Interrupting Traffic 2.9 MB |
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1950 | Modern Communications In Yards and Terminals 1.4 MB |
1926 | Directing Trains By Signals 1.9 MB |
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1944 | CTC Speeds Ore Traffic On the DM&IR 4.6 MB |
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1950 | SS Protection 2.1 MB |
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1932 | Burlington Installs Extensive New Electric Interlocking 3.6 MB |
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1931 | One Electric Interlocking for Two Drawbridges 3.1 MB |
1937 | Signaling on the Wabash 3.7 MB |
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1935 | New Signaling on the Route of the C&NW "400" 9.6 MB |
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1950 | CTC on the Wabash 2.6 MB |
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1949 | Modern Signaling on a Division 6.6 MB |
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1946 | Pere Marquette Installs CTC 3.1 MB |
1954 | CTC Increases Capacity of Double Track 4.2 MB |
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1954 | CTC into Service 2.5 MB |
1946 | CTC on 121 Miles of the Cotton Belt 6.4 MB |
1947 | Railroads Request Relief from the ICC Signal Order 465.0 KB |
1936 | Reconstruction of Interlocking at the Dallas Union Terminal 14.8 MB |
1928 | Signal and Train Control Hearing Ends 2.0 MB |
1941 | Signaling on 47 Miles of St. Louis Southwestern 12.6 MB |
1944 | St. Louis Southwestern Installs Centralized Traffic Control 6.9 MB |
1947 | Territories Involved in the ICC Signaling Order 399.0 KB |
1944 | Track Circuits on Passing Tracks in CTC Territory 941.8 KB |
1956 | Train Operations When CTC Fails 3.5 MB |
1954 | Why Cotton Belt Installed CTC On 429 Miles of Single Track 4.0 MB |
1947 | Territories Involved in the ICC Signaling Order 399.0 KB |
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1947 | Territories Involved in the ICC Signaling Order 399.0 KB |
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1947 | Territories Involved in the ICC Signaling Order 399.0 KB |
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1950 | Consolidation of Interlockings 2.5 MB |
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1928 | Burlington Completes Automatic Signals Chicago to Denver 5.1 MB |
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1928 | GN Replaces Semaphores with Color Light Signals 1.2 MB |
1947 | ICC Holds Signal Hearing 507.5 KB |
1935 | New Signaling on the Route of the C&NW "400" 9.6 MB |
1947 | Railroads Request Relief from the ICC Signal Order 465.0 KB |
1935 | Safety of High Speed Trains 5.2 MB |
1935 | Signaling for Higher Train Speeds 3.0 MB |
1935 | The "400" to Run on Six and One Half Hour Schedule 942.0 KB |
1915 | Extension of New Haven signals 684.8 KB |
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1924 | Signal Development in Connection With Single Phase Propulsion 5.1 MB |
1911 | A Comparison of the Interlocking Laws of the Various States 2.6 MB |
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1935 | Multiple Aspect Signaling 3.3 MB |
1939 | The Problem of Medium Speed 835.3 KB |
1928 | Train Signs or Indicators 468.2 KB |
1954 | General Railway Signal Company Enters Fiftieth Year 1.6 MB |
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1936 | T. George Stiles Rounds Out 60 Years of Signaling 2.5 MB |
1928 | Dispatcher Signaling System Operates Through Sleet Storm 1.1 MB |
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1928 | Electric Plant on NYC Replaces Two Mechanical Plants 3.2 MB |
1927 | NYC First to Install Complete Train Dispatching System 8.0 MB |
1931 | Results of Centralized Control on NYC 703.8 KB |
1928 | Changes on the C&NW 978.4 KB |
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1943 | CTC on the Bessemer & Lake Erie 8.7 MB |
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1956 | Plastic Track Model Is Big Picture for Levermen 1.4 MB |
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1931 | Centralized Traffic Control Installed on Wabash 5.6 MB |
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1910 | Mechanical Interlocking at State Line 1.0 MB |
1947 | Hoosac Tunnel Interlocking and CTC 1.7 MB |
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1936 | Annunciator Circuits 2.6 MB |
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1926 | Train Control Progress in 1925 3.1 MB |
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1911 | Signaling on the Illinois Traction System 1.5 MB |
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1923 | C&O Installs Signaling With Train Control 5.8 MB |
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1928 | C&O Signaling and Train Control Facilitate Operation 4.1 MB |
1943 | Railway Signaling in North Africa 3.5 MB |
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1954 | CTC Improves Train Operation 3.3 MB |
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1937 | Ends of Double Track Controlled by CTC 12.4 MB |
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1945 | Accident at Movable Point Crossing 546.8 KB |
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1910 | The Multiple Unit Electric Interlocking Machine 1.5 MB |
1909 | Union Switch & Signal’s Inspection Trip 1.5 MB |
1956 | Interlocking Relays 3.9 MB |
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1947 | Annual Review and Outlook 425.1 KB |
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1947 | Railroads Request Relief from the ICC Signal Order 465.0 KB |
1911 | Automatic Signals on the Chicago Great Western 7.4 MB |
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1940 | Personal: Changes on the New York Central 2.2 MB |
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1921 | Stop or Proceed vs. Stop and Proceed 335.2 KB |
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1921 | Stop or Proceed vs. Stop and Proceed [reply] 330.8 KB |
1935 | Cab Signals and ATC on UP Streamliner 2.1 MB |
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1936 | Demands for Modern Signaling 12.1 MB |
1937 | Track Shunting Problems 947.3 KB |
1937 | Track Shunting Problems 2.5 MB |
1943 | Centralized Traffic Control on the Milwaukee 2.8 MB |
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1941 | Code-Following Polar Track Circuit Relay 1.4 MB |
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1941 | P4 Code-Following Relay 1.1 MB |
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1924 | A New Triangular Light Signal 1.7 MB |
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1950 | Neon Lighting For Crossing Gate Arms 3.1 MB |
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1938 | Adapting Signaling to Requirements 1.7 MB |
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1954 | CTC Improves Train Operation 3.3 MB |
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1920 | Electro-Mechanical Interlocker at Sunbury, PA 538.5 KB |
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1924 | Results of Train Control Test on Pennsylvania 3.1 MB |
1925 | Train Operation by Signal Indications – Especially by Cab Signals 1.3 MB |
1915 | Duluth Terminal Trestle Signaling 2.3 MB |
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1954 | CTC Moves Heavy Trains 4.1 MB |
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1954 | Modern Signaling in New Subways in Stockholm, Sweden 6.7 MB |
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1913 | The AGA flashlight a success in Sweden 326.2 KB |
1937 | Railway Signaling by Wireless 1.6 MB |
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1922 | Controlled Manual Block in Hauenstein Tunnel 3.4 MB |
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1937 | Remote Control on the Pennsylvania 5.2 MB |
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1913 | The Union’s Signaling Exhibition Room 1.5 MB |
1915 | Switch and Lock Movements in Mechanical Plants 2.0 MB |
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1940 | Facing Point Locks On Main Line Switches 2.6 MB |
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1935 | Inspecting Switch Circuit Controllers 1.7 MB |
1935 | Switch-Stand Selector 1.9 MB |
1935 | Removal of Switch Indicators 2.3 MB |
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1937 | Switch Indicators Serve as Interlocking Control Devices 5.6 MB |
1937 | Electric Switch Lamps on the Santa Fe 4.5 MB |
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1937 | Switch Lamps in Automatic Territory 1.2 MB |
1950 | New Developments 16.9 MB |
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1941 | Protection at Hand-Thrown Switches in CTC Territory 1.6 MB |
1943 | Signals Ordered on the Kansas City Southern 1.4 MB |
1947 | Signaling and Interlocking in Italy 684.8 KB |
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1950 | New Developments 16.9 MB |
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1949 | Main Line Crossovers 2.4 MB |
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1935 | Obsolescence in Signaling 3.4 MB |
1956 | Switch Machines for CTC 2.0 MB |
1956 | Switch Machines for CTC 985.3 KB |
1935 | Switch-Stand Selector 1.9 MB |
1935 | Operating Long Switch Points 2.4 MB |
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1941 | Protection at Hand-Thrown Switches in CTC Territory 1.6 MB |
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1937 | Switch Protection in Automatic Territory 3.0 MB |
1956 | CN Telegraph Moves Into Its New Home 8.1 MB |
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1935 | Facing Point Locks on Switches 3.2 MB |
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1940 | Testing Switches 1.1 MB |
1950 | CTC Extended on the Rio Grande 4.4 MB |
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1922 | Controlled Manual Block in Hauenstein Tunnel 3.4 MB |
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1952 | CTC Pays Its Way on B&O 733.2 KB |
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1911 | Automatic Signals on the Chicago Great Western 7.4 MB |
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1911 | Suggestions as to the Standard Symbols 1.9 MB |
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1911 | Symbols and Nomenclature for Written Circuits 2.3 MB |
1936 | New York Central Interlocking at Syracuse 15.9 MB |
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1936 | All-Relay Interlocking On NYC at Syracuse 29.7 MB |
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1936 | New York Central Interlocking at Syracuse 15.9 MB |