Plimsoll Day is to dedicated to the memory of Samuel Plimsoll, a member of the English Parliament who championed sailors’ safety while traveling the world’s waterways in crammed ships. He was instrumental in the amendment of Britain’s Merchant Shipping Act, which came about in response to the then – national problem of dangerously overloaded ships. Plimsoll’s bill, named the Unseaworthy Ships Bill, was passed in 1876, and required that a mark be present on a ship’s hull to indicate the waterline at which maximum cargo capacity was reached for the vessel. For the law merely required that said line – which came to be known as the Plimsoll Line, or the Plimsoll Mark – be painted on the boat. It did not say the line had to be an accurate representation of the safe waterline position for the ship’s cargo load. That little stipulation didn’t make it’s way into law until 1894. Today, the Plimsoll Mark is universally recognized, and is actually represented by several lines – each one indicating the safe waterline mark in relation to both cargo type and water type (salinity, temperature, ocean region, and season).

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