A Method of collecting Salt Petre from the Air which is talked of here is this. Take of Lime and Ashes equal Quantities, and of horse dung a Quantity equal to both the Ashes and Lime, mix them together into a Mortar, with this Mortar and a Quantity of long Straw to keep it together build two Walls Eighteen Inches thick, and three feet high, about four feet asunder. Then make a Center and turn and
This is one Method as it is affirmed by Gentlemen here.
Sulphur, Nitre, and Lead We must have of our own. We must not depend upon Navigation for these. I wish the Committee of the General Court for Lead and Salt would transmit their Discoveries to me. I dont know whether you are one of that Committee or not.
Pray inform me if Obrian and Carghill1 were or were not commissioned by some Vote of the general Court, and whether they cant be put into the Continental service. An order is gone to Genl. Washington to that Purpose if it can be done.
Mentioned earlier by JA to Warren, 13 Oct. (above).