Stake or Stump Anvil :
Modern Flame Cut Design by Jock Dempsey
The reason for the rectangular shank is to fit into an anvil stand made by laminating 1-1/2" thick framing lumber. To set the anvil all that would be required is to cut a rectangle out of the center board before glueing up the base. The alternative is to leave the shank full thickness and let the user create larger hole. This is cheaper, more efficient use of material and results in a heavier anvil.
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