[ 14 ] therefore a tobacco, plater, I would certainly try what might be done with a bed of mould made of refuse tobacco, and doubt not but it would fully answer my expectations. However, that might prove these hasty and perhaps seasonable hints are offered to the consideration of his countrymen, by a sincere and faithful friend to America. Those plants which contain Salt-Petre always sparkle when they are thrown into the fire. But there is another less equivocal method of knowing whether a plant contains any quantity of this Salt. Bruise the plant well and press the juice from it. Put this juice into an earthen pot, and place it in a cool cellar, first pouring a little sweet oil upon the surface of it to prevent its becoming mouldy. If the plant contains any Nitree, you will find it in the form of crystals on the sides of the vessel in six weeks or two months. The method of extracting the Salt-petre is nearly the same whatever ingredients we may employ for making it. The ingredients are put into tubs, barrels, or hogsheads, perforated at their bottoms. Rain, river, or very pure spring water, is poured upon them, which gradually dissolves all the salt they contain, and conveys it drop by drop into vessels provided to receive it. The nitre in this state contains a large quantity of common salt. Before I explain in what manner this salt is to be separated from the Nitre, it will be necessary to premise that bare evaporation, by boiling or otherways, will crystalize common salt, but that cold and rest are necessary to crystalize Nitre. The lee, (if I may so call it) made from the materials
