#570. To Soften Cast-Iron, for Drilling

- By Formula pot

Ingredients

  • Refer procedure

Procedure:

Heat to a cherry red, having it lie level in the fire, then with a pair of cold tongs put on a piece of brimstone, a little less in size than you wish the hole to be when drilled, and it softens entirely through the piece; let it lie in the fire until a little cool, when it is ready to drill.

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