After passing through the stratum which was commonly called the water lime, about ten feet in thickness, the workmen came to a more compact mass of primitive grey limestone, which however was not penetrated to any great depth. In many parts of the excavation, masses of bluish white flint and horn stone were found enclosed in, or encrusting the fetid limestone. And from the large quantities of arrow heads and other rude formations of this flint stone, it is evident that it was made much use of by the Indians in forming their weapons of war and hunting; in one place a magazine of arrow heads was discovered, containing many hundreds of those rude implements, carefully packed together, and buried below the surface of the ground.
The existence of iron ore in considerable quantities was exhibited in the progress of excavation of the canal by numerous highly charged chalybeate springs, that gushed out and continued to flow during the time that the rock was exposed, chiefly in the upper strata of limestone.[13] The canal when built was intended for the largest class of boats, but the facilities for navigation have so far improved and the size of vessels increased so far beyond the expectations of the projectors of this enterprise that it is now found much too small to answer the demands of navigation. The consequence is that the canal is looked upon as, equally with the falls, a barrier to navigation. The larger lower-river boats refuse to sign bills of lading, compelling them to deliver their goods above the falls, and as this class of boats is increasing, it promises soon to be as difficult to pass this point as before this immense work was completed. As previous to the undertaking of this canal, so there are now numerous plans proposed for overcoming the impediment; and these do not differ materially from those suggested and noticed in 1804. The only ground upon which all parties agree is, that whatever is done should be effected by the general government, and not left to be completed by individual enterprise.
The government, as has before been said, owns a very large part of the stock in this canal, say three-fifths, and it is strongly urged by a part of the community that nothing would better serve the interests of western navigation than a movement on the part of the United States, making it free. The question of internal improvement is not within the province of this history to discuss, but certainly a deaf ear should not be turned by the general government to the united voice of so many of its children, all alike demanding to be relieved from their embarrassments, and the more particularly so, as it has already heard and answered the supplications of a part of its numerous family. Any semblance of favoritism in a government is a sure means of alienating the trust and affection of a part of its dependants. Whatever means may be most advisable to effect the removal of the impediment to navigation here should at once be adopted. And if the opening of the canal freely to all could tend to effect this object, the government has already had from it revenue sufficient to warrant it in taking off the tax from navigation. Up to the year 1843, there had passed through this canal, 13,776 steamboats, and 4701 flats and keels, making in all 2,425,567 tons, the tolls of which amounted to $1,227,625 50. It would not be an unfair calculation to rate the expenses of keeping up the canal at $30,000 per annum, or $390,000 for the thirteen years above referred to. Supposing the government to possess three-fifths of this profit, it would amount to $502,575, or nearly enough to build a new canal. It is not to be wondered at, then, that western people should feel disposed to murmur at having these large sums of money taken from their waters and applied to improving the Balize or Sandy Hook, or any other distant part of the Union. And the matter is the more grievous when it is remembered that these tolls are not only not free but are enormously and disproportionately high. Whether laden or not, each boat is obliged to pay at the rate of 50 cts per ton, in proportion to her capacity, as a toll! The whole subject is one deserving immediate and earnest attention, as involving interests in which not only Louisville, but the whole South and West is intimately concerned.