With such an adventurous character as he possessed, Cavelier de la Salle could not learn of the exploration of the course of the Upper Mississippi without burning with the desire to complete the discovery and to descend the river to its mouth. Robert Rene Cavelier de la Salle was born at Rouen about the year 1644. He belonged to an excellent family, and was well educated. From his earliest years he was passionately fond of stories of travel, and the older he grew the more cramped he felt in the civilization of Europe; like the mettled mustang of the vast prairies of America, he longed for the immensity of unknown plains, for the imposing majesty of forests which the foot of man had not yet trod. Maturity and reason gave a more definite aim to these aspirations; at the age of twenty-four he came to New France to try his fortune. He entered into relations with different Indian tribes, and the extent of his commerce led him to establish a trading-post opposite the Sault St. Louis. This site, as we shall see, received soon after the name of Lachine. Though settled at this spot, La Salle did not cease to meditate on the plan fixed in his brain of discovering a passage to China and the Indies, and upon learning the news that MM. Dollier de Casson and Gallinee were going to christianize the wild tribes of south-western Canada, he hastened to rejoin the two devoted missionaries. They set out in the summer of 1669, with twenty-two Frenchmen. Arriving at Niagara, La Salle suddenly changed his mind, and abandoned his travelling companions, under the pretext of illness. No more was needed for the Frenchman, _ne malin_,[7] to fix upon the seigniory of the future discoverer of the mouth of the Mississippi the name of Lachine; M. Dollier de Casson is suspected of being the author of this gentle irony.