But the beauty of Micas Falls and the wildness of the Santa Rosa remained with Ken. Where did that river go? How many waterfalls and rapids did it have? What teeming life must be along its rich banks! It haunted Ken. He wanted to learn the mystery of the jungle. There was the same longing which had gotten him into the wild adventures in Penetier Forest and the Grand Canon country of Arizona. And all at once flashed over him the thought that here was the jungle river for him to explore.

"Why, that's the very thing," he said, thinking aloud.

" What's wrong with you," asked Hal, "talking to yourself that way?"

Ken did not explain. The train clattered between green walls of jungle, and occasionally stopped at a station. But the thought of the jungle haunted him until the train arrived at Tampico.

Ken had the name of an American hotel, and that was all he knew about Tampico. The station was crowded with natives. Man after man accosted the boys, jabbering excitedly in Mexican. Some of these showed brass badges bearing a number and the word Cargodore.

"Hal, I believe these fellows are porters or baggage-men," said Ken. And he showed his trunk check to one of them. The fellow jerked it out of Ken's hand and ran off. The boys ran after him. They were relieved to see him enter a shed full of baggage. And they were amazed to see him kneel down and take their trunk on his back. It was a big trunk and heavy. The man was small and light.

" It '11 smash him!" cried Hal.

But the little cargodore walked off with the trunk on his back. Then Ken and Hal saw other cargodores packing trunks. The boys kept close to their man and used their eyes with exceeding interest. The sun was setting, and the square, colored buildings looked as if they were in a picture of Spain.

"Look at the boats and canoes!" cried Hal, as they crossed a canal.

Ken saw long narrow canoes that had been hollowed out from straight tree-trunks. They were of every size, and some of the paddles were enormous. Crowds of natives were jabbering and jostling each other at a rude wharf.

" Look back," called Hal, who seemed to have a hundred eyes.

Ken saw a wide, beautiful river, shining red in the sunset. Palm-trees on the distant shore showed black against the horizon.

" Hal, that's the Panuco. What a river!"

" Makes the Susquehanna look like a creek," was Hal's comment.

The cargodore led the boys through a plaza, down a narrow street to the hotel. Here they were made to feel at home. The proprietor was a kindly American. The hotel was crowded, and many of the guests were Englishmen there for the tarpon-fishing, with sportsmen from the States, and settlers coming in to take up new lands. It was pleasant for Ken and Hal to hear their own language once more. After dinner they sallied forth to see the town. But the narrow dark streets and the blanketed natives stealing silently along were not particularly inviting.