About The Union for Technological Development.

Created by Blackberry Pie for the UTD

Produced 156 cobble in 236sec(just under 4 minutes)
approx 39 cobble/min ; approx 0.66cobble/sec

Most efficient use is to run the machine until it is full(at which point it auto-shuts off), then turn it off manually, and mine the cobblestone sheet.
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Machine may uncommonly(usually deliberate user error) leak lava which beaks up to 3 pieces of circuitry: a torch, a repeater, and a wire. Said circuitry pieces are marked with iron blocks for servicing convenience.