What??? Nobody has ever heard of a clothesline prop!??? Mom's was a double strand of No. 9 wire on tee posts about fifty feet apart. She would have to wipe the rust and bird doo off it each time before she used it. It was at her shoulder height so she could hoist the heavy overalls up without extending her arms out full length(very tiring).
Depending on the ground moisture in the clay, the tee posts would sag forward under the weight, or twist with an unbalanced line--so a prop was always used. Otherwise it was overalls, overalls, shirts, shirts, shorts,shorts,----shorts, shorts, shirts, shirts, overalls, overalls.
Luckily the prop was permanently attached with a fence staple--or she would have used it on me on occasion.
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