Sherman necktie

A Sherman necktie is a length of railroad rail that has been heated until it glows red, then twisted into a loop or knot before cooling. The result is a piece of metal permanently deformed and unusable for track. The term comes from Union General William Tecumseh Sherman's destructive march through Georgia and the Carolinas during the American Civil War, when his forces used this method to disable Confederate rail lines.

The process requires heating a rail section, typically around 6 to 12 feet long, in a fire hot enough to make the steel plastic rather than brittle. Once sufficiently heated, the rail is twisted using leverage (historically by hand, using bars or chains) or later by machinery. As it cools, the steel hardens in its deformed state. The twisted loop cannot be straightened without cutting or severe damage, and even cutting produces short, warped segments that are scrap metal.

Why it worked as sabotage

A single Sherman necktie would stop a rail line without requiring systematic destruction of the entire track bed. The method consumed less time and fewer resources than tearing up rails wholesale. More importantly, Confederate forces could not simply remove and re-straighten twisted rails: the deformation was permanent and the rails were destroyed, not merely displaced. This made repair significantly harder than defense against track removal alone.

The method relies on a specific temperature window and material property. Steel between roughly 1,200 and 1,500 degrees Fahrenheit becomes malleable enough to twist but not so soft that it loses structural integrity. Rails made of wrought iron or early steel (with varying carbon content) could be twisted differently; modern high-carbon rail steel is more brittle when heated and less amenable to this sabotage. The effectiveness of the technique was partly circumstantial to 19th-century rail composition.

The term survives in rail industry vocabulary as a historical reference and appears in documentation about track damage assessment and destruction prevention. While the practice itself belongs to military history, the word remains useful shorthand for a particular form of malicious rail deformation, distinguishing it from other damage patterns that inspectors and forensic analysts might encounter.