A Practical Reference Book for the Use of Prospectors, Miners, Investors and Mining Men; with a Description of the Principal ... To find the area of a circle multiply the square of the diameter by .7854, or multiply half the diameter by half theanbsp;...

Title | : | Prospector's and Miner's Manual |

Author | : | Orville Hugh Packer |

Publisher | : | - 1913 |

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