The eastern slopes of the Andes attracted our attention in 1950, when it became probable that the Marajoara Phase on the island of Marajó at the mouth of the Amazon was derived from northwestern South America. Our first opportunity to investigate the possibilities for archeological fieldwork came when we were in Guayaquil, Ecuador, in 1954 and met Coronel Jorge V. Gortoire, who had served for a period as commandant of the Ecuadorian Army Post at Tiputini. Conversation with him reawakened our latent interest in the area, and we began to make specific plans. In October 1956, having been awarded Grant No. 2012 from the Penrose Fund by the American Philosophical Society and granted official detail by the Smithsonian Institution, we returned to Ecuador to undertake the fieldwork.
Through the courtesy of Coronel Rafael Andrade Ochoa, at that time Commandergeneral of the Fuerza Aerea Ecuatoriana, we received authorization to fly from Quito to Tiputini in an Ecuadorian Air Force DC-3 transport plane. However, almost daily rains maintained the airstrip in unsuitable condition for landing and after several weeks of waiting in Quito for the weather to break, we gave up and arranged to fly by commercial airline in a Junkers Tri-Motor to Shell-Mera and then in a single engine Norseman to Tena. A day on horseback brought us to Latas, where we secured a dugout canoe manned by Quechua-speaking Indians to take us downriver. Although the trip was longer and more difficult than it would have been by air, it gave us invaluable first-hand experience with conditions along the Rio Napo (pls. 1-5). We were able to follow our hourly progress on U.S. Air Force Preliminary Base Map 950A (Scale 1: 500,000), which perfectly reproduced every bend and island. By the afternoon of the fifth day, when we arrived at Tiputini, we were well prepared to appreciate the comments of Orellana's men, who preceded us by 415 years.
When we stepped on shore at Tiputini, the military post that was to be our base of operations, we were delighted to discover not only that there was an archeological site on the spot, but that the pottery included incised and excised techniques of decoration diagnostic of the Marajoara Phase, although only painted vessels had been previously reported from the Rio Napo. With the cooperation of army personnel and local residents, we were able to investigate a number of sites particularly along the portion of the river between Tiputini and the mouth of the Rio Yasuní, which marks the boundary between Ecuador and Peru. We also checked the lower Rio Tiputini. During our stay, the river was unusually low, and extensive sand bars reduced the channel in places to a slender meandering stream (pl. 4b). Giant trees temporarily resting on beaches (pl. 3b) attested to the force of the current at other times of the year, lending credence to descriptions by Orellana's companions (see pp. 106-107), who had the misfortune to encounter higher water than we did.