This is a riveting firsthand account of Leonard Clark’s search for the legendary Seven Cities of Cibola – reputedly home to enormous reserves of gold – in the Amazon rain forest east of the Peruvian Andes. En route, he acquires vast knowledge about the lives of indigenous peoples.

A former U.S. Army intelligence officer, Clark is joined on his expedition by Inez Pokorny, a gutsy, multilingual female sidekick and fellow explorer. Their treacherous journey includes encounters with headhunting JÖvaro Indians, man-eating jaguars, forty-foot-long anacondas, poisonous plants, and shamanistic healers.

“An exploration to rival Lewis and Clark’s, remarkable both for its sense of adventure and for the breadth of its reporting.”
– Joe Kane, author of Savages and Running the Amazon

To write a few opening words to Leonard Clark’s record of exploration is a privilege not often granted to an American official on the ground. Here is a book to get one’s teeth into; extremely exciting and informative. Clark has actually traversed at least two of the worst regions off the main Western Amazon rivers – regions inaccessible even to the armed forces of the countries claiming this vast jungle area.

I notice he has written only on the exploring phase of his great trip, and sincerely hope a second book follows encompassing the long-occupied regions also known to him, and now an important part of the interlocking economy and social life of the greater world without. Clark is a former intelligence officer and thoroughly competent in methods of collection. His knowledge is detailed and indeed profound.

If you put your hand on this narrative you cannot shake it off. Clark has told his story as it was actually lived in the jungle. Clark’s book is filled with fascinating new information – and with him we learn; but with him also we itch from the hellish bites of strange bugs; we sweat and are blinded under a glaring equatorial sun; we taste the feeling of despair from starvation; we hear the anaconda’s ghost-hiss of night-tracking headhunters, under the influence of strange drugs such as the Soul Vine. We are overwhelmed by the same sickening smells when a witchman lets a poisonous snake bite him deliberately; we know the terrible sense of the explorer’s uncertainty – the question of going forward into the eerie, living, creeping silence of the great bush, or retreating to safety – when the maps prove to be all wrong…

This of course is a new kind of Amazon expedition; for Clark has contrived in an informal and fascinating manner to combine information with adventure, something very rare in the literature of the past. And knowing him in the Amazon country personally, I can say he had no help, no official sanctions, few material assets. It was all completely without fanfare, though now that the expedition is accomplished Clark is in danger of becoming a legend in these parts. For capital, he had only courage; labor there was – of a grim and terrible kind. Clark above all others has proved that even in our workaday world, great rewards, moral as well as those measurable in gold, still are possible to him who dares the unknown.

I am a hunter myself, and am grateful that he has included tales of hunting in the jungles. So little of this – due to almost insurmountable difficulties in heavy jungle – is included in exploration accounts (excepting a few hunts in President Theodore Roosevelt’s River of Doubt, in the more open terrain of the Brazilian Mato Grosso).

In his Appendices of the Western Amazon, I must say that the information is 95 percent new. Certainly the wildlife providing hides, feathers and meat, the trees, fishes, medicines and other useful products such as petroleum and gold, will provide priceless material for a study on the possibility of a hundred new exports to the United States and Europe.

I see he has used foreign italicized words only when an English rendition is not quite applicable. For instance, a quebrada in the Andes is certainly not a gulch, but a sort of Grand Canyon wrinkle in the earth’s crust; a playa is certainly not a beach as we visualize a beach, but a particular kind of riverine sand bank or even an isolated bar, etc.

I respectfully differ with Clark on the length of the anaconda snake. The one he measured on the Morona River was 26 feet 8 1/2 inches. That is much too conservative. The Peruvian skin traders who bring thousands a year to Iquitos tell me anacondas quite often measure up to 40 feet. The Englishman, Colonel P. H. Fawcett, (who was lost while searching for a ruined city which he believed to be Atlantis) once killed an anaconda measured at 65 feet. In the Beni Swamps of Madre de Dios, Fawcett saw snake tracks which led him to estimate their length up to 80 feet. In the Beni also, the Colonel saw an animal he believed might beDiplodocus, the 80-foot reptile of twenty-five tons. This animal he thought might still be in existence as it was an eater of aquatic plants, which grow profusely in this region. TheDiplodocus story is confirmed by many of the tribes east of the Ucayali, a region covered by Clark.

A note of warning must be sounded to prospectors who might attempt to reach the new gold- and oil-bearing regions. It is very dangerous even when fully equipped, the many diseases are often fatal, transportation is non-existent, many of the tribes off the main rivers are savage. Because Clark got through alive is no reason to suppose that many others could do the same. The jungle-wise soldiers themselves have been thrust back time and again, often with heavy losses.

Clark has not mentioned his own personal background and qualifications, and I think it important as an explanation of why he was able to succeed where others have failed. He has been exploring the waste places of the earth, on all its five continents, for twenty years. No other such explorer is active today. He is not of the same class as other modern-day explorers – that is, geologists, botanists, ethnological collectors, etc. – but that rare Victorian type, the trail-breaker: the true explorer whom all others must follow.

Clark’s background, enabling him to obtain the secret information on the slave practices, is fantastic. He has not mentioned it, but he was actually the original pioneer of the United States armed services behind the Red Army and the Japanese Army lines, in charge of our underground organizations, guerrilla activities and our espionage systems in China, Mongolia and other countries in World War II. He has also been private advisor to the Arab League in Egypt, and to various princes and lamas in Mongolia and Tibet and to at least five warlords in China. He personally took the unofficial surrender of Formosa from General Enriki Ando three months prior to its occupation by Chiang Kai-shek and the American Forces.

Clark is the only true Tibetan explorer ever produced by the United States, excepting W. W. Rockhill, over a century ago. Clark reached the headwaters of the Yellow River. He mapped this area, together with the western ranges of the Amnyi Machen. As leader of the official Chinese Nationalist Expedition, his equipment and retinue were vast; a large staff of scientists, hundreds of troops and carrier animals, sent out by Governor Ma Pu-fang. No doubt this was the greatest field expedition of modern times.

And what a contrast, due to lack of material assets, what an incredible contrast, to Leonard Clark’s Amazon venture!

Louis Gallardy
Consular Agent

Foreword to the New Edition



An Historical Note

I We Enter at Hazard
II “Beyond Lies the Unknown…
III We Become Slave Traders
IV Brother of the Snake
V “We Can’t Go Back!”
VI “What Shall We Do Now, Amigo?”
VII Kill! Kill!
VIII Bible and a Tiger
IX Our Lord Be Praised
X The Bellbird
XI Signal Smokes!
XII The Killing of the Catsiburere
XIII The Soul Vine
XIV Captives of the Cannibals
XV Escape on the Tambo
XVI Ucayali Adventures
XVII “Why Don’t You Take Inez Along?”
XVIII Drums on the Marañ Ã3n
XIX Headhunters in the Headwaters
XX Troubles and Revelations
XXI Stranded Among the Aguarunas
XXII The Cities and the Gold of El Dorado


  1. Dangerous Snakes
  2. Edible Fish and Turtles
  3. Valuable Trees
  4. Useful Flora
  5. Fruits and Food Plants
  6. Jungle-Indian Pharmaceuticals
  7. Campa Indian Vocabulary

Chapter 1

We Enter at Hazard

Every explorer has two faces, the secret one and the one he shows to the world. Both my faces hid the fact that I had $1,000 in my shirt pocket, secured by a safety pin, everything I owned in this world converted to ten $100 currency bills. It wasn’t much, but I was after treasure, and every treasure hunter is optimistic. If he weren’t optimistic he would be something else, but never a treasure hunter. True, at the moment I didn’t know where the gold was buried, but I did have a clue – one single, solitary, threadbare clue.

This clue I had obtained in the United States on May 1st, and it was June 10th, 1946, when I crossed south of the Equator and landed by Panagra plane at Lima Airport in Peru. I was dusty, disheveled, hatless and relieved, for the long flight had been repeatedly delayed since leaving San Francisco, California, on June 1st. In addition to my small cash stake, I had a brief note from an old-time American resident of Peru, to one Miguel Maldonaldo – a Peruvian who might possibly know the location of legendary El Dorado, somewhere in the unexplored upper Amazon basin.

I already knew that Peru was an ancient and highly civilized country, and that the people were said to be among the world’s most cultivated, still, I never suspected that this culture would extend to the airport officials. But by all the officials, including even the Customs, I was smilingly passed into Peru, a free man and without a worry to his name. To reap the benefits of face, so important in South America (and perhaps in North America as well), I put up at the city’s finest, the magnificent Hotel BolÖvar, suite 216, facing the Plaza San MartÖn.

From this base I began hunting down my Peruvian and also trying to find an experienced jungle partner. After five days of threading the lovely old Spanish city with its flower-embowered patio walls and brown-wood balconies, searching out any number of itinerant Señor Maldonaldos, I learned that the Peruvian had left on a trip into the monte, but would return to Lima in a few weeks.

As to that second man, the partner whom I hoped would act as guide, I was assisted by the American Consulate people and by Colonel J. H. O’Malley, our Military Attaché, but no one could be found who would go under-financed into such a desolate region. Three weeks passed.

Maldonaldo finally returned to Lima, and after swearing on his mother’s grave as to its authenticity, gave me a yellowed, badly cracked and very old Spanish parchment map of El Dorado, in exchange for a $100 bill. Of course, there was no way possible of cross-checking such a document; I simply had to take his word for it, and the hunch of my old friend back home, and go. Like the priesthood, treasure hunters burn with a faith and trust incomprehensible to the man in the street. Once he sees a treasure map, he will believe even his worst enemy, let alone a friend. I was here because of that belief, and here was a real map to substantiate that faith and hope. I simply had to find that lost land of treasure, El Dorado, no matter what it had cost others in disappointment and tragedy. Except for that $1,000 I was broke, for I had lost a considerable fortune through bad investments in China and the United States. Although I can look back now with a calm detachment, still at the moment, in Lima, I simply had to have that gold, and with the same unreasoning desperation that grips a man who loves a woman – he has got to have that one woman, though a billion others exist in the world. I knew too, that anyone rumored to be searching for El Dorado would be placed under surveillance – for there are strict treasure-trove laws regarding this sort of thing – and so great would be the rewards of its discovery that even his life would be in jeopardy.

My going into the high bush was secret, and my “cover” was that of looking for medical secrets of the Indian brujos (witchmen).

I was now reduced to a desperately small $700 working capital.

I decided I must leave Lima within the next few days, if not sooner. While in search of vital information on the regions ahead, I talked to Professor Cesar Garcia Rosell, head of the oldest scientific institution on the hemisphere, the Sociedad de GeografÖa. He was charming, enthusiastic and surprisingly cooperative; a very young man in spite of his sixty-five years. I did not dare to rouse the savant’s skepticism by mentioning my true purpose in going into the interior, but as for my decision to go there in “search of medicine,” I was frank.

Together Rosell and I studied his mouldy old Jesuit maps of the tierra incognita, the unbroken jungle lying east of the Andean Cordilleras. The whole strip – believed to be mostly flat-lands – called Loreto and Madre de Dios, was disputed between Peru on the one hand, and Brazil, Bolivia, Colombia and Ecuador on the other. From Madre de Dios in the southeastern quarter near Bolivia and the headwaters of the Purus and Juruá in Brazil, all the way north to the Ecuadorian and Colombian frontiers on the Napo and Putumayo, the strip averaged 1,100 miles long by 400 to 500 wide. Its eastern edge was backed up somewhere against the westernmost regions of wildest Brazil, inhabited by the cannibal Cunibos, the headhunting Mashcos on the Rio Manú, and such killers. Rosell explained that fully 90 percent of this largely disputed region was recognized by the government (which obtained its statistics from him) as completely unexplored territory on which no white man had ever left his footprint.

“Then, what are all these names on the maps?” I asked.
“Señor – please! They are only names! Sometimes an abandoned thatched hut on a main river bank… Only names, to fill the great white spaces. The governments of the five claiming powers must have colonies there, must they not? – to substantiate…”

The professor continued, saying that soldiers and rubber tappers, barbasco gatherers had covered but 8 to 10 percent off the main rivers, and few records had been left concerning La Selva (The Forest), as the Peruvians poetically called this worst jungle region in the whole Amazon basin. Nearly all the original parchment reports of the long-banished Jesuits, who had been recalled to Spain in 1767, plus the later reports of the few explorers and Indian-fighting Army officers, had been lost in a recent fire at the Society’s offices. He then warned me that twenty bona-fide expeditions, fully armed and equipped, many having soldiers, had come to grief on the basin’s 50,000 miles of navigable waterways in recent years. Everywhere the bravos were rising against further intrusion. And as for the vast, desolate desert-jungle lying unbroken between the greatest rivers, very little, almost none – if the truth were known – had actually been traversed. My track must lie across these areas and I must realize they were perilous and incalculable.

In effect, for he used both Spanish and English, his very words were:

“Señor Clark, you enter at hazard; there is a grave chance you will not get out alive from Madre de Dios and Loreto, should you be so unfortunate as to penetrate even a little way after crossing the Andes. Your head could be cut off and reduced to 2 1/2 inches. You should know that in the last ten years, we have lost approximately 700 Peruvian explorers, soldiers, officials, patrÃ3nes and bushrangers, who have tried to get off the rivers and ‘pacify’ the Indians. The explorer Robuchon is only one famous case of an investigator being eaten by cannibals, but I could name scores of unknown explorers who have fallen into the hands of the corpse-eating tribes, and those of the headhunting enclave. For every Colonel Fawcett known to the world, there are a hundred such who have disappeared and remain entirely unheard of.”

Had I taken into account the many white-water rapids, unknown waterfalls which blocked the Andean watershed rivers? Also the forests would be denuded of all game and other foods. He believed man-eating jaguars were common. He spoke also of death from snake-bite, black crocodiles, paña (two varieties, cousins of the Brazilian meat-eating piranha). He mentioned the danger of the ten-foot cannibal zúngaro – tiger-fish, giant electric rays capable of electrocuting a man; even fresh-water sharks 3,000 miles (by twisting river beds and channels) from the salty ocean. There were scores of diseases; and ants whose single bite will cause blindness. In short, a hundred lethal possibilities existed.

“Usually our men just disappear. We never hear from them again. Others often go insane. If they get out alive they are incompetent for any sort of work. We have just received a report from the mouth of the Morona River north of the Marañ Ã3n. Juan Vargas is our mapper there. He has been found in the belly of a snake, the yacu maman, in his own screened launch. Our government launches have a heavy wire mesh carefully covering sides and roof so that the poison darts of the Indians will be caught in them. Vargas was sleeping on the boat. The crew were camped on a safe playa (river beach). The anaconda, apparently hunting food, came out of the river and entered the boat through a hole torn that day in one corner. After killing and swallowing Vargas, it could not return through the hole, and was found in the engine room next morning.”

“Is it possible to swallow a man whole?” I asked. “How about a man’s shoulders passing the jaws? Most experts have doubted Indian claims that certain varieties of those snakes can swallow a deer weighing a hundred pounds.”

Rosell laughed indulgently, though quietly, as befitting his position. “These snakes are capable of swallowing not only a 150-pound man, but a 500-pound animal such as a tapir. You see, they crush the larger bones, lather the head and unjoint their jaws. After swallowing its food, the snake’s digestive juices are so strong that even large bones are dissolved. When hungry the snake will take any kind of living food – marine, crocodiles, land mammals and even man himself.”

“Señor Clark,” Professor Rosell concluded, rather coldly clinical and with that manner of infinite patience assumed by Peruvians when talking with the skeptical, inexperienced gringo, “it is imperative, life and death to you, that you correct your mistaken ideas that the jungle is not dangerous. These ideas no doubt you obtained from the works of so-called explorers who have not themselves lived in the true, unexplored inner jungles but have spent only a short time on some main river, or operated a few leagues from a base on the edge of the forest.”

As he talked, I took notes in my cryptic brand of shorthand:

“Herpetology: scores of poisonous snakes, not much known. Rosell has glass tubes (thirty poisonous snakes from the Ucayali River alone). Divided into two general families: colubrids and vipers. Says African and Asian cobras are colubrids. Here represented in the ring snakes – corals, genus Elaps, short-fanged (which, like cobras, hang on and chew after striking). Pit vipers much worse. Have two subfamilies or genera; first, the many tropical cascabels (rattlers – Crotalus horridus); second, genus Lachesis, like bushmasters in Guianas, aggressive, vicious, no rattles (to warn you with), exceedingly poisonous, very large. West Indies’ fer-de-lance here called jararaca sometimes shushupe (long-fanged snake), night-rover, 94 percent fatal. Have one of this family only three inches long – most deadly of all. Rosell says snakes have killed more people in single year than have all the elephants, lions and buffaloes of Africa since beginning of historical times.”

At this point Professor Rosell stopped to mop his brow with a linen handkerchief.

“Now! The colubrid victim suffers more than any other; because of the shock to his nerve centers, his blood is incapable of coagulation and becomes watery, often breaking out through the eyeballs. Some of these venomous reptiles, especially the vipers, will attack man without provocation. We do not know why; we only know they are irritable and vindictive, and account for the deaths of hundreds of our rubber gatherers, soldiers, patrÃ3ne Indians (workers) and others who live on the edges of the great forest, or clearings on the main rivers within it. Our rattler types are often enormous, thick as a man’s thigh; their surprisingly plentiful white, creamy-thick venom does not paralyze the nerve centers but coagulates the blood, destroying the corpuscles. Of course…you have anti-venom!”

Now South Americans believe all norteamericanos to be rich; and though purposely I had arrived in Peru by a subsidiary of Pan American Airways, I had not dared tell Professor Rosell I had no funds to purchase anti-venom. I knew from previous experience in Latin America he would consider me a hopeless visionary, a crank, and so cease his briefing – which to me could well mean success or failure on the road to El Dorado.

I thanked Señor Cesar Garcia Rosell, and took my leave. I have no wish to appear melodramatic when I say that I was apprehensive of what the future might hold…

Leonard Clark was perhaps one of the greatest of all twentieth-century explorers. He did not believe in big expeditions and elaborate paraphernalia – he was a man who carried his own belongings and charged ahead. This same trait enabled him to perform extraordinary feats of military intelligence and reconnaissance in difficult and dangerous areas during World War II. Clark attended the University of California, then joined the army, attaining the rank of colonel. During the war, he spent many months in China behind Japanese lines organizing guerrilla activity. His post-war expeditions began in Borneo, and over the years he made trips to Mexico, the Celebes, Sumatra, China, India, Japan, Central America, South America, and Burma. He was the author of two other books, A Wanderer Till I Die and The Marching Wind. He passed away in 1957 at the age of 49, while on a diamond-mining expedition in Venezuela.