👨‍🔬Science Travel on Instagram: "🧵 The Amazing Working Principle of the Sewing Machine Now, sewing is done with the push of a button, but old sewing machines moved by hand power, not electricity. They used a hand-turned crank or a foot-operated pedal to move the needle. The needle sends the upper thread down below the fabric, and the bobbin (a small spool wound with thread) underneath catches that thread and interlaces it with the lower thread. At this moment, the two threads interlock, creat

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