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Improving refrigerator railcars
Early wooden refrigerator railcars required insulation to help protect their contents from extremes in temperature. “Hairfelt” was compressed cattle hair, placed into the floor and walls of a railcar. It was inexpensive (a byproduct of the slaughtering process), yet quite flawed. Hairfelt would last three to four years, but it would decay, which rotted the car’s wooden partitions and often tainted the cargo...
