At the beginning of the present century the anthracite or stone coal was in general use, in all the districts where it was found, as a fuel for the blacksmith’s fire and the iron worker’s forge. This, however, was the limit of its utility. It was thought to be necessary to force a strong artificial air current up through it to make it burn, and since this could not well be done in grates, stoves, or furnaces, there was no demand for coal for domestic use, or for the great manufacturing industries. Efforts were indeed made to overcome this difficulty. Schemes without number were set on foot and abandoned. It was proposed, at one time, to force air through a tube to the under part of the grate by means of clockwork operated by a weight or by a spring. But the cost of such an arrangement made it impracticable. It seems, however, that Weiss, Cist, and Hillegas, who were developing the discovery made by Ginther in the Mauch Chunk mountain, also solved the problem of burning the stone coal without an artificial draft. They had sent specimens of their coals to Philadelphia, and presumably had accompanied them with instructions as to the proper method of burning them. This presumption is borne out by certain letters sent to Jacob Cist of Wilkes Barre, a son of Charles Cist the printer, who was in company with Weiss and Hillegas. Two of these letters are now in the possession of the Wyoming Historical and Geological Society at Wilkes Barre. An extract from one of them reads as follows:―― “I have experienced the use of them” (the Lehigh coals) “in a close stove and also in a fireplace that may be closed and opened at pleasure, so constructed, as to cause a brisk current of air to pass up through a small contracted grate on which they were laid. I find them more difficult to be kindled than the Virginia coal, yet a small quantity of dry wood laid on the grate under them is sufficient to ignite them, which being done, they continue to burn while a sufficient amount be added to keep up the combustion, occasionally stirring them to keep down the ashes. They produce no smoke, contain no sulphur, and when well ignited exhibit a vivid bright appearance, all which render them suitable for warming rooms.” This letter is dated “Philadelphia, Feb. 15^th 1803,” and is signed “Oliver Evans.” The second letter is similar in its recommendation and report of success, and states that the writer, “Fred^k Graff, clerk of the Water Works of Phil^a ... made a trial of the Lehigh coals in the year 1802 in the large stove at the Pennsylvania Bank in Phil^a.” So far as is known these are the first recorded instances of any successful attempts to burn anthracite coal in grates and stoves. Dr. James of Philadelphia has also left on record the fact that he made constant use of anthracite coal for heating purposes from the year 1804.