The danger of the system was in making the national purse an object of plunder for Congressmen, and the consequent danger of unholy alliances and combinations for looting the public treasury. It is interesting that for so long a period as it was in vogue there were so slight symptoms of this sort of thing; and men little knew that, by acting on liberal lines at the time, despite the dangers and risks, they were exerting a power to shape the new nation, to incite private investment, to encourage State and private works of promotion, and to aid the commercial awakening of a people to an activity and an enterprise whose possibilities cannot at the present day be estimated. Take the Portland Canal around the historic "falls of the Ohio" at Louisville; this was a work for no one State in particular to perform, not even Kentucky; it was a detriment to Louisville itself, for it destroyed the old portage business, as the Erie Canal ruined the overland carrying trade between Schenectady and Albany. All the States bordering on the Ohio were benefited by this improvement, as was equally true respecting the Government's improvement of the Ohio River itself, which began in 1825. The Portland Canal was one of the important investments which tended to prove the financial benefit of such investments. The Government's total subscription of stock was $233,500; when the affairs of the Company were closed in 1874 by the purchase of the canal by the Government, it was found that the national profit (in mere interest) had been $257,778. This was due to exorbitant tolls charged by the Company, which resulted, finally, in the purchase of the canal and throwing it open toll-free.