The question at issue, under the provisions of the boundary treaties, as formulated by the American Commissioner and accepted by the Mexican Commissioner at the session of the Commission on November 6, 1895, was "whether or not the river in its passage moved over the land by gradual erosion from the Mexican bank and deposited on the United States bank, as described in Article I of the treaty of 1884, or by sudden avulsion, by cutting a new bed or deepening another channel than that which marked the boundary." The case was tried at El Paso by Commissioner Osorno and myself; Messrs. Maillefert and Happer being the secretaries of the Commission, and Messrs. Corella and Dabney consulting engineers. We limited the witnesses to four of the most trustworthy of the older inhabitants on each side. Their testimony showed there was no basis for any claim that there had been any avulsion or cutting of a new bed. The change in the channel was clearly erosive, although at certain or rather "uncertain" times and places during floods the erosion had been much more rapid than others, and had been visible to the naked eye, since as the lower substratum of sand was washed out, the upper layer of clay along the concave or Mexican bank would cave in, sometimes in considerable chunks. The building up of the convex or American shore, however, had always been imperceptibly gradual. The Mexican Commissioner reduced his argument to the following syllogism: "Major proposition: Any change other than slow and gradual does not alter the boundary line (Article I of the Convention of November 12, 1884). "Minor proposition: Since the change of the river in the case denominated 'El Chamizal' _was not slow and gradual_, but, on the contrary, violent and at periods of time of unequal intermissions (which has been fully demonstrated above). "Conclusion: Thence, the change of the river at the lands of 'El Chamizal' does not alter the boundary line marked in 1852 by the International Boundary Commission (Article II of the Convention of 1884)." I held that the treaty "clearly specifies but two classes of changes in the river," namely, erosive and avulsive, and that "any other unspecified change, as is implied in the major proposition of the syllogism of the Mexican Commissioner, we have no authority to consider, but that our respective conclusions must be in favor of one or the other, as specifically stated in the treaty." I furthermore held that: "The syllogism of the Mexican Commissioner must be rejected, not only because its minor proposition is not proven, but because it is abundantly disproven by every witness who testified in the case save Serna." I further pointed out that in my opinion: