1629 Va. Acts 151, Acts of March 24th, 1629, Act 5,

For the better furtherance and advancement of staple commodities, and more especially that of potashes and saltpeeter, it is thought fit that every master of a family within the several plantations of this colony shall use their best endeavors to preserve and keep in dry and tight houses or casks all those ashes that shall proceed and be made by the wool that is burned in clearing their grounds . . . And that every master of a family shall have a special care, after a notice thereof given, to preserve and keep all their urine which shall be made in their several plantations. . .

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