Charles XII. employed the engineer Polheim to plan a navigation across the kingdom, upon the line pointed out by Bishop Brask, viz. through the lakes Wenern, Wiken, Wettern, Boren, and Roxen, and to the town of Norkoping, which had now supplanted the more direct line to Soderkoping ; and the excellent channel from the Baltic up to the latter was interrupted by a clumsy wooden bridge. The plans of Polhcim are still preserv ed ; he was of a bold and enterprising character, probably influenced, in some measure, by that of the soveleign under whom lie acted ; and the celebrated falls of Trol hatta, in the great river Gotha, furnished a fit subject for such minds. To connect the navigation fnarn the river Gotha with the lake Wenern, Polheim formed the design of damming up these falls, by building walls across the rapid torrents of Trolhatta, and constructing three locks, having altogether a rise of 114 leet. A contract was absolutely entered into between the king and the engineer, not only for this, but the whole navigation across the country to the Baltic ; but the death of this brave and extravagant monarch suspended the project. In 1746, the Trolhatta scheme was approved of, and Polheim, though old, was consulted by the resident en gineers. In 1755, three locks were excavated in the rocks, along one side of the falls, and gates of a particu lar construction were placed in the uppermost. Ore arm of the stream, in the uppermost fall, was dammed up, which yet remains. A great dam cicross the whole river, beneath the last fall, was nearly. completed, when it was wholly carried away by the force of the stream on the 20th September 1755. About 900 dozen of pianks had, the preceding day, been thrown into the ri% er, for what purpose has not been ascertained; but having ac cumulated in a mass against the unfinished dam, proved the immediate cause of its destruction. This left the impression of impracticability on the minds of the coun try.; and excepting the construction of a bad lock at Carlsgraff, all remained in a dispirited state until 1772.
Meanwhile the Arbcga canal having fallen into a state of decay, in the year 1768, the town of Orebro, being much interested in this communication with Stockholm, offered to reconstruct the works, to which the crown agreed, and the whole was given up to the town.
In 1767, instructions were given to NI. Thomberg, (who, in 1757, had given a plan for Trolhatta, nearly the same as the one executed,) for a new survey between _ . _ the lake Wetfern and the Baltic ; and similar instruc tions were given to Captain Rook, who reported that the line by Soderkoping WaS by much the best, and re commended that the project should be undertaken by a private company. In 1774, M. Thomberg's opinion was again taken up by the king respecting the whole navigation across the kingdom ; and a lock and side cut were constructed on the river Gotha, by the side of the cataract of Akerstrom, which, with the lock at Edit, perfected the navigation from Gothenburg to the Trolhatta falls. As these were 114 feet ascent upon 8000 feet in length, a wooden railway was constructed; and the locks at Karlsgraff were, in 1778, reconstructed in a more perfect manner. In 1781, 1782, 1783, and 1784, AI. Thomberg was employed in his surveys across the kingdom, and he was of opinion that Soderkoping was the best termination ; however no practical mea sures were then adopted.
In 1765, plans were produced for an inland naviga tion from the province of Daleme to the Maelar, called the Stromsholm Canal, which had been proposed in 1737. This was undertaken by individual subscription,
with some aid from the crown. The work was com menced in 1777, and completed in 1795. The whole length is about 60 English miles; the fall 336 feet ; the number of locks 25. The length of some are 80, of others 66 feet; their breadth is 18 feet ; and the canal has 471- ket of water. This is a very imperfect naviga tion, being a mixture of natural water courses. The chief articles transported are pig and bar iron, to the amount of 4000 English tons annually.
Another communication, most of which remains to be performed, is to connect the lakes in thc province of Ostrogotha, between the towns of Linkoping and Wim merby, under the name of the Kindx Canal. It was proposed in 1756, probably by the famous Colonel Pcch lin, who, at his own expense, made several cuts, and took other measures respecting it.
Thus we find, for the space of three centuries, the cranal business a constant object of public attention, and frequently treated with great earnestness, but still with very little effect. It must therefore be inferred, that there is a certain degree of civilization, public wealth, and trade, necessary to support such improvements. Previous to this they are merely possible, when the means, capacity, and desire, happen to be united in a sovereign or a state, when they may be forced prema turely, as in the case of Charles XI. the Czar Peter, Frederic of Prussia, and Louis XII. But, besides the before-mentioned general difficulties, there are others peculiar to Sweden. The numerous large lakes render it imprudent to think of employing vessels, or connect ing canals of small dimensions, and, consequently, in the very 6rst essays great means are required. Sweden may he supposed to have reached the period at which inland navigation might be attempted with advantage, when, on the decease of Gustavus 111. the regency of the kingdom was entrusted to his brother the late king. The want of an uninterrupted navigation was strongly felt, and a plan for passing Trolhatta was laid before the king hy a company of subset ibers, in 1793. It con sisted of a cut from a small bay immediately above the falls, along a rocky hank, to a precipice, where it was to descend by nine locks, mostly excavated out of the solid rock, after which it entered the river at a considerable distance below the falls. where the water was placid. In order to encourage the project, the locks which had been constructed at Edit and Ake:strops, savelal pieces of land, and a certain quantity of gunpowder, were grant ed by the crown to the company, Oil condition that they executed the canal to the breadth of 22 feet, with a deptli of 64- feet of water, in the course of six years. The tolls for the whole navigation were fixed at 3s. 3d. English per ton for iron, as the chief article of export. Other articles paid in proportion. The subscription,amounting to 765,000 rix dollars, was filled up. Al. Nordwall was appointed chief engineer; and the canal and locks were completed in the month of August 1800. The whole navigation between the town of Gothenburg and the lake Wencrn is now the property of the company ; and the revenue amounts to 9 per cent. upon their capital ex pended, which was only about 55 per cent. of the sum subscribed.