Still the prices which coal commanded in the Philadelphia market were not sufficient to pay for the labor of mining it and the cost of shipping it. So that, prior to 1818, nearly all the coal mined in the Schuylkill region was sold to the blacksmiths of the surrounding country. In that year, however, the improvements of the Schuylkill navigation were completed, and afforded an additional, though not by any means safe or sufficient, outlet for the products of the mines. By 1826 and 1827 the growing importance of the coal trade became manifest, the Schuylkill navigation system was placed in excellent repair, and the mining business of the district grew rapidly to enormous proportions. The northeasterly extension of the Wyoming coal basin, leaving the Susquehanna River at Pittston, follows the valley of the Lackawanna up to a point seven miles beyond Carbondale, where it cuts slightly into the counties of Wayne and Susquehanna, and there runs out. This extension is known as the Lackawanna region. Coal was dug up and experimented with here at the beginning of the present century. Its outcrop at the river bank was noted by Preston, a surveyor, in 1804. In 1812 it was mined at Providence and burned in a rude grate by H. C. L. Von Storch. About this time the brothers William and Maurice Wurts, having been attracted by the mineral wealth of the region, came there from Philadelphia and began explorations for the purpose of ascertaining the location, area, and quality of the beds of anthracite coal. William, the younger brother, in the course of his wanderings through the rugged hills and thick forests of the country, chanced to meet a hunter by the name of David Nobles, who, having fled from the adjoining county of Wayne to avoid imprisonment for debt, was leading a precarious existence in the woods. Nobles was well acquainted with the country, knew where the outcroppings of coal were, and having entered into the service of Wurts, rendered him most valuable assistance.