This story came from “Emily” who writes about rail history on the whole current Metro-North system.
Milk has long been a staple of the American diet, and since the New York and Harlem Railroad was founded up until the 1950s, it was also a staple commodity carried by rail. Early in New York City’s history, dairy cows were kept and milked in the city proper near distilleries. Often sick cows were kept in cramped conditions, and fed the byproducts of whiskey making – resulting in a blue tinted “milk” that was lacking in cream content and dangerous to drink. Unscrupulous businessmen used additives – including water, sugar, molasses, egg, and even plaster of paris – to give it the appearance of fresh milk and sell it to an unwitting public. This tainted milk led to an increased infant mortality in the city, and was coined the “Swill Milk Scandal” when exposed in the periodicals of the day. The scandal eventually led to regulation of the milk industry, and a push for “pure milk” from dairies far outside the city. Stepping up to transport this milk were, of course, the railroads.
Milk depots were established at many train depots, and local farmers could bring and sell their milk, which was then transported to the city. One of the Harlem’s most famous freights was the Rutland Milk train, which brought milk to New York City from Vermont – transferring from the Rutland Railroad to the Harlem in Chatham. Every day a swap would occur where a train full of milk changed hands at Chatham, exchanged for the previous day’s empties.