[164] The Americans are now rapidly developing their large natural resources of iron. “The iron ores of the United States” (London _Times_, 28th of May, 1875), “are plentiful and various, though some kinds are wanting; thus the ‘spathose’ or spar-like iron ore, scarce even in Europe, is very rare; and the ironstone of the liassic and oolite seams, which furnishes about one-third of our British pig-iron, appears to be wholly absent. On the other hand, the specular iron ore, the brown and red hematites, the clay and blackband ironstones, are good and abundant; and some of the deposits of magnetic iron ore—as at Lake Champlain, and at Cornwall, in Pennsylvania—are very remarkable. At Cornwall the deposit consists of a solid hill of ore, measuring roughly 500 feet in diameter, rising from the ground level to a height of 350 feet, and proved by borings to a depth of 180 feet below ground level. The iron mine at Port Henry—at the south-west corner of Lake Champlain, in the State of New York—is worked in a huge prism of ore, about 200 feet square, and descending at an angle of 26 to 40 degrees, to an unknown depth, the superincumbent rock being supported by pillars of solid ore, 40 feet square at the base and about 20 feet at the top, with a height of considerably more than 100 feet.” [165] _Ante_, p. 42. [166] “Encyclopædia Britannica” (eighth edition), vol. xx. p. 639, “Steam Navigation.” The _Savannah_ was full rigged as a sailing-vessel with auxiliary steam power, and her paddles were removable. [167] Dr. Lardner, in his “Encyclopædia” and elsewhere, had more than once expressed the opinion that no steam-ship would ever be able to make so distant a voyage as that of crossing the Atlantic, without recoaling. Having entered on details with regard to this important question in a lecture he delivered at Liverpool in December 1835, I consider it desirable to give the following extract from it, as reported in the _Liverpool Albion_ of the 14th of that month, the matter being one of considerable historical interest: