[1] Many years after his wife's death, and shortly before his own, Mr. Cooper dictated the following passage, which is almost the last in his _Reminiscences_:-- "Not only do I think of my wife during my waking moments; she often comes to me in my dreams, sometimes once a week, sometimes once in two weeks, and sometimes at longer intervals. It is one of the greatest pleasures of my life that I can believe that she has been, and is now, my guardian angel, and it is one of my happiest hopes that I shall see that this our world is but the bud of a being that is to ripen and bear its choicest fruits in another and a better." [2] Letter of Morse to the Secretary of the Treasury in the autumn of 1843. IV INVENTIONS THE inventions projected, though in many instances not perfected or successfully introduced, by Mr. Cooper constitute a long list and cover a wide field. A few of them may be mentioned here, in addition to those to which allusion has been made already. It will be seen that even those which failed of commercial success generally contained the germs of future mechanical progress, and bore witness to the extraordinary vigor and versatility of his genius. When the Erie Canal was approaching completion it occurred to Mr. Cooper that canal boats might be propelled by the power of water drawn from a higher level and moving a series of endless chains along the canal. After some preliminary experiments he built a flat-bottomed scow, arranged a water wheel to utilize the tidal current in the East River, and actually achieved a trial trip of two miles and return, in which Governor Clinton and other invited guests took part. The governor was so well pleased that he paid Mr. Cooper eight hundred dollars for the first chance to purchase the right of applying the method on the new canal. But the scheme failed for the reason (as Mr. Cooper explained half a century later) that the right of way for the Erie Canal had been secured from the farmers of the State by representing to them the profit which they would realize from selling forage, etc., for the use of canal boats, which were to be drawn by horses or mules. The introduction of mechanical power would destroy these inducements, and the plan was abandoned,--though Mr. Cooper had demonstrated its feasibility by running his endless chain on the East River for ten days and carrying hundreds of passengers over the trial route. It is not likely that such a use of water power on the Erie Canal would have proved practicable on a large scale; but the endless chain, which Mr. Cooper apparently considered as a minor feature only, has been adopted since, and lies at the basis of the famous Belgian system of river and canal transportation.