Pushing through the steaming jungle, a Venezuelan army major named Franz Antonio Rísquez Iribarren scrambled to the top of a high cliff in the Parima Mountains and proudly planted his flag at the summit. He measured the cliff’s map coordinates and radioed to his superiors: “In the name of Almighty God, glory to the brave people, we have accomplished our mission. An embrace of admiration and gratitude to all . . .” From the same spot, last week the American Geographical Society in New York got word from Dr. José Cruxent, archaeologist for the expedition: “Greetings from the headwaters of the Orinoco.”
The search for the source of the Orinoco River has long been a favorite obsession among explorers of South America’s jungles. The jaundiced waters of the third largest river in South America sprawl across the breadth of Venezuela like a gigantic fishhook. The shank fans out into a delta just below Trinidad. The barb is buried far to the southwest, deep in the tangled wilderness of the Parima Mountains. For the past four centuries adventurers and scientists have hunted its headwaters.
Missionaries & Soldiers. Spanish conquistadors thought they would find there the fabulous El Dorado. Jesuit missionaries took the word of God as far upriver as Esmeralda. In 1800, Baron Friedrich Heinrich Alexander von Humboldt took an expedition farther than any scientist before him, and the world of botany was enriched with more than 6,000 species of new plants. Humboldt also discovered a link between the water systems of the Orinoco and the Amazon.
Not many years later an itinerant Brazilian claimed to have traveled the length of the river. In 1931, an American, Dr. Herbert Spencer Dickey, also made the trip (TIME, Aug. 10, 1931), reported what he declared were the exact coordinates of the Orinoco’s source: Lat. 2° 25 min. 30 sec. North, Long. 63° 45 min. 31 sec. West. Then, in 1943, a Brazilian boundary-setting expedition claimed that it had found the source 30 miles to the west. U.S. Army flyers from British Guiana helped to confirm the location of the river’s origin.
Mermaids & Indians. Early this year, Colombian-born Hector Robert Acebes Medina organized a small expedition to find the source of the Orinoco all over again and study Indian tribes along the way. According to Acebes, he was within 100 miles of his goal when Venezuelan authorities chased him back to San Felipe in Colombia. He had studied the Indians, and had seen, so he said, some toninas —strange mermaidlike mammals with breasts like a woman’s and the strength to defeat alligators in aquatic battle. But he was not permitted to re-enter Venezuela and continue his travels.
Last summer Major Rísquez Iribarren’s men set out to settle the matter once & for all. They beat their way to Esmeralda before they were stopped by sickness and lack of food. Last month, 22 camps and a few parachute supply drops later, they reached their goal.
Most of the distance they traveled by log canoe, moving overland when rapids and falls made the river too dangerous. Swarms of mosquitoes and jejenes ( a tiny black gnat whose bite raises large welts) harassed them all the way. The high, thick jungle along the river banks cut off the sun and every portage had to be hacked clear with machetes.
In that dank forest where the Orinoco is a turbulent but puny brook, numerous tributaries tumble through the Parima Mountains. By measuring the varying rates of flow of these mountain streams, Major Rísquez Iribarren’s men determined what they are sure is the true path of the river. Their observations also located the source of the Orinoco at Lat. 2° 18 min. North, Long. 63° 15 min. West, a few miles to the west of where
Dickey placed it 20 years ago. But until the expedition returns with more scientific evidence, cautious geographers will not start redrawing their sketchy maps of one of the world’s last frontiers.
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