He and Francisco backed water and stared. So did their passengers, and well it was that the canoe had been stopped. From the lower branches of a large leafy tree jutting out into the very course of the canoe was hanging a long, mottled object, swaying and weaving. Charley saw the head--a snake's head! A boa constrictor, as large around as a barrel, and with most of its body hidden in the tree! "Ha!" exclaimed Mr. Grigsby, and raised his rifle. With single movement the two boatmen swung the canoe broadside and held it. The Fremonter sent eagle glance adown his leveled barrel--the rifle cracked and puffed a little waft of smoke. "Spat!" sounded the bullet. The huge snake began to writhe and twist, fairly shaking the tree; then fold by fold it issued, in a horrid mazy line of yellow and black (would it never end?), until with a plash the last of it fell into the water and swirling the surface the monster disappeared. "Bueno! Bueno! Mucho culebra (Good! Good! Big snake)" exclaimed Maria; and chattering in Spanish he and Francisco hastily veered the canoe further from the bank. "They say the snake's mate is liable to be near and we'd better stand out," explained Mr. Adams. "He was a big one, sure." "Forty feet, I judge," answered Mr. Grigsby. "Where'd you hit him?" asked Charley, eagerly. "In the eye," asserted Mr. Grigsby. "You don't think a Fremont man would shoot for any other mark, do you?" Mile after mile steadily paddled Maria and Francisco, up the magic river. Already their bronze bodies, sinewy and naked, were glistening with perspiration, for in here, between the high wooded hills, it was very hot and moist. Charley's neck was tired, from twisting his head so that he could see everything at once; and on their seat amidships his father and Mr. Grigsby were constantly craning right and left. Abruptly Maria and Francisco ceased paddling, threw aside their plaited hats, kicked off their cotton trousers, and crying together "Bano! Bano!" plunged overboard. Charley gazed in alarm. What had happened? Another boa threatening? But his father and Mr. Grigsby read his alarmed face and laughed. "Oh, they're just taking a swim, that's all," explained his father. "They said 'bano,' which is Spanish for bath." Nevertheless, this struck Charley as a dangerous thing to do, in a river swarming with alligators and other reptiles; yet frisking about and blowing and ducking Maria and Francisco seemed to be enjoying themselves. They swam like seals. "We might as well have a snack to eat, while we wait," quoth Mr. Grigsby. He threw Charley some bananas, and cut off chunks of the dried meat for the company. By the time they three had eaten a little lunch, Maria and Francisco had climbed aboard, donned their trousers and hats, and resuming their paddles were starting on again, evidently much refreshed.