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The genius of the Tudor ice shipping scheme centered on three simple principles. First, the ice was free and was harvested locally from Fresh Pond, Walden Pond and other ponds and lakes in the area. The only cost was the labor to cut the blocks. Secondly, after much trial and error, Frederic discovered that layering sawdust between the blocks of ice provided the best insulation for the journey. Sawdust was the byproduct of the local sawmills, again free. Lastly, ships often left Boston Harbor empty, heading to the West Indies to pick up exotic produce and goods. Filling the holds with Tudor ice for the voyage south allowed Tudor to negotiate better shipping prices.
From: Historic Houses of the Month Frederic Tudor and Charlestown’s Ice Trade.
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