^^^ I have an old pic (from the 1920's) of two of my uncles when they were teens.
They are sitting next to a sawn tree taking a break. The saw they had looks just like yours. (yours might have finer teeth)
One of them told me, when I was about that age, they would sometimes spend the whole day working that crosscut saw. It's no wonder in that age there weren't very many 'out of shape' young adults.
I don't think gas chain saws were around yet. (or they couldn't afford one)
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