What is this?
What was it used for?
Who would have used it?
How is it connected to mass media?

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Answers:
What is this?
This is a hand-crank seeder, made around 1910 by the Rittenhouse company in Indiana.
What was it used for?
It was used on farms to sow seeds onto prepared soil. Seeds were loaded into the cloth hopper on top and the crank was turned, sowing the seeds, or "broadcasting" them — which is where we got the word we now use to describe radio and other communications!
Who would have used it?
Hand-cranked seeders were used on farms until the 1940s, when the technological leaps brought with the Second World War saw the rise of mechanical seeders. After the war the supply of materials for mechanical seeders was suddenly plentiful, and farm use dwindled. But the explosive postwar growth of suburbia gave these seeders new uses in lawns and gardens.