“Well, I’m about to go off on a river of doubt of my own,” I cautioned. “It may be a few weeks before you see it again.” That was no problem for John; so I took it home and put it on the bed stand to dip into during the last moments of consciousness each night.

It turned out to be a page-turner, and led to several very late nights. The story of ex-President Theodore Roosevelt’s ill-advised exploration, in 1913-1914, of a previously unknown river in central South America, it’s captivating for its descriptions of the unforeseen difficulties of the two-month-long overland approach to the river, the unexplored jungle and waterfalls along its steep descent, and the almost slapdash preparation for what became a major expedition that very nearly cost the ex-president his life.

Roosevelt was, of course, renowned for his embrace of the vigorous life. His tales of youth in the newly settled West, his reckless derring-do during the Spanish-American War, and his stories of big-game hunting in Africa (I read his African Game Trails so often as a boy that the binding finally disintegrated.) fired the American imagination. He’d been deeply chagrined by his humiliating loss in the 1912 Presidential election, and needed – as he always did when matters grew pressing; depression ran in his family – to get away for a bit. In planning a South American speaking tour, followed by an expedition to an utterly unknown tropical river, he clearly had no idea what he was getting into. But he was nothing if not game.

Until fairly recent days, exploratory expeditions have had to include a scientific component in order to secure funding. So it was with this one; two scientists were among the “officers.” Roosevelt’s son Kermit, who’d just become engaged to an American socialite and was in a state of romantic pining, went along, ostensibly to watch out for the old man’s health: For all his robust protestations, Roosevelt had a game leg, injured years before in a traffic accident, which turned out to be, in the event, his literal Achilles’ heel. There was also, unaccountably, a Catholic priest with some South American experience, who hoped to gain fame by his association with the former President. If the expedition had been a rock band, the best name would have been Mötley Crüe.

The man in charge of provisions, Anthony Fiala, had been involved in attempts to reach the North Pole, but had no experience in supplying tropical expeditions. In addition, he went a bit over the top in his choices for the Presidential party – condiments, gallons of olive oil, ginger snaps – and the resulting mountain of supplies was necessarily whittled down as the expedition’s animals died on the two-month trek to the put-in spot on the river. Roosevelt sent back several of his original companions, or detailed them to follow other rivers, until there were only two of them left.

Colonel Roosevelt, as he was known, was co-leader, with Colonel Cândido Rondon, head of the Brazilian Strategic Telegraph Commission, who knew the area probably better than anyone else alive. But whereas Colonel Roosevelt’s goal was to explore the river with dispatch and come out the other end triumphant, Colonel Rondon’s was to survey the river very carefully for the government. I know from even my own travels that conflicting goals can rupture the morale of a group under stress; Roosevelt and Rondon did indeed clash.

The expedition, as described by Ms. Millard, was a running fight with doom. Biting, stinging insects; gloomy rain forests virtually barren of sustenance for the men; rock-strewn rapids and cataracts that shattered several of the dugout canoes; malaria and infections; and the constant threat of unseen and very unhappy natives — not to mention imminent starvation – combined to reduce the men and officers to sickly, shambling shadows. Yet the impassable rapids continued, and had to be passed one way or another. They lost one man to drowning in the rapids, another to murder; and a third – the murderer and a malingerer – abandoned to his fate in the jungle. At one point, Roosevelt, so sick with an infection that the expedition doctor and his friends despaired of him, decided, in order to let the others survive, to take the lethal dose of morphine that he carried with him always. When he realized that Kermit would attempt to carry his body out, he relented.

As I said, a page-turner, though I get the impression that the author, a Midwesterner, has been neither a whitewater paddler nor a member of an expedition. The book contains a lot of filler – aside from the journals and reports that were her major sources, there’s much speculation about the unseen natives’ decisions, as well as derivative descriptions of the rain forest, epiphytes, and rubber trees. She carelessly calls one of my favorite camping foods, Erbswurst, “a type of sausage.” It’s actually dried pea meal and smoked bacon formed into a sausage shape; you crumble some into hot water and – voilà! – pea soup! Knorr still sells it, over 100 years later. Still, she’s written a fascinating story from the life of an archetypal Manifest Destiny American, as well as of his family, dogged as it was by depression and suicide, yet soldiering on. Five stars!