Several attempts have been made to explore this river. The story of one that was undertaken under the Bolivian Government has been told with such exaggerations as almost mark it a work of fiction, by Lieutenant Van Nivel. A tragic interest attaches to the expedition of Dr. Crévaux, of the French Geographical Society, who undertook to work along the banks of the river. The party were enticed inland by the savages and murdered. A later Bolivian expedition of one hundred troops, accompanied by a French traveler, M. Thouar, were harassed but not actually attacked by the savages, and, after wandering considerably out of their course, succeeded in reaching the Paraguay, having traversed the Chaco in a southeast direction more or less along the river, but without in any manner elucidating its geography.
- Dr. Crévaux, already distinguished for his work in exploring the boundary of Guiana and Brazil, was commissioned to endeavor to reach the opposite side of the Amazon Valley by way of the upper Paraguay. At Buenos Ayres the members of the local Geographical Society interested him in the idea of tracing the course of the Pilcomayo. So, instead of ascending the Paraguay, he went by railway to Tucuman, crossed the Bolivian border on the 16th of January, 1882, and made his way to Father Doroteo's mission, San Francisco, on the Pilcomayo. At about the same time a military expedition sent against the Toba Indians of the Chaco to punish them for some depredations had returned, bringing seven children as prisoners. It was deemed best to send a messenger to them—a Toba woman named Galla or Petrona, who had lived for some time at the mission—to learn how they would receive the explorers. The messenger did not return, but, as was afterward learned, instigated the Indians to murder Dr. Crévaux and his companions. The party, numbering twenty persons, without waiting longer, started on the 19th of April. On the 27th of the same month they were all massacred but one.
M. Thouar started from Santiago in May, 1883, on hearing that the Tobas held as prisoners two survivors of the Crévaux expedition. Following Crévaux's steps from Tarija and the advanced post of Caiza, he reached the scene of the massacre and founded there toward the end of August the colony Crévaux. He learned, from a number of the aborigines whom he interrogated, that none of the Crévaux expedition survived; but, not satisfied with what the Indians affirmed, he plunged into the unknown region and undertook with fifty Bolivian soldiers to descend the Pilcomayo in the midst of the hostile tribes. His party, which was weakened from time to time by desertions, descended the right or Argentine bank of the river, plunged through deep, brackish marshes, narrowly escaped a surprise by two thousand Indians, repelled an attack by eight hundred of them, found further traveling through the swamps impracticable, and crossed over to the other side of the river; and, finally, in October, having reached the beginning of the great delta of the Pilcomayo, gave up the attempt to follow the river further, and took the shortest course for the Paraguay, which they reached after a month's journeying in great suffering. M. Thouar returned to the exploration in 1885, and, starting from the southern part of the delta, went up by land eighty leagues to the place where he had left the Pilcomayo on his former expedition, and thence descended the river in a canoe to its mouth. After this he was engaged by the Bolivian Government in two attempts to find a route for a wagon-road
miles in diameter, while above this swamp it was filled with falls, rapids, sand-banks, and snags. The bed of the latter oscillated backward and forward to the extent of thirty or forty miles, carrying with it great trunks of trees of very hard wood, the specific gravity of which exceeded that of water. The rainy season was succeeded by one so dry that animal life almost perished for lack of water. There was a distance of twelve hundred and fifty miles along the Bermejo to its mouth in which it received but one branch.—Editor.