ic, and was immediately appointed President of the Peruvian
Hydrographical Commission of the Amazon. He left Lima with a full
corps of assistants, and made his way across the mountains to the head
of navigation on the Palcazu river, where the party was received on
board a Government steamer that had been dispatched from Iquitos to
meet them. The headquarters of the Commission was established at
Iquitos, the principal settlement on the Upper Amazon river, and the
place where the Government factories and magazines were located.

In the small steamer _Naps_, belonging to the Government, Tucker made
an exploring expedition of two hundred and fifty miles up Yavari, the
river which forms the boundary between Peru and Brazil.

None of the Peruvian steamers on the Amazon being suitable for
exploring and surveying purposes, the Government at Lima ordered
Tucker to proceed to the United States and procure such a vessel as
was required for the duty pertaining to his Commission. In obedience
to this order Tucker spent some months in the United States, and had a
steamer built by Messrs. Pusey, Jones & Co., of Wilmington, Delaware,
expressly adapted to the navigation of the shoals and rapids of the
Upper Amazon. This vessel, named the _Tambo_, was delivered to Tucker
at Para, the Brazilian city at the mouth of the Lower Amazon.
Embarking on board the _Tambo_, Tucker took the steamer up the river
to Iquitos, where supplies were taken on board sufficient to last for
several months. He then proceeded to make an important expedition up
the Upper Amazon, the Ucayali and the Tambo rivers. The Tambo river
had never been explored, and it was thought that it presented a
feasible route for navigation to San Ramon, a military station in the
heart of the interior, only about thirty miles distant from the large
and important city of Tarmo, which is connected by railway with Lima.

Leaving Iquitos, the _Tambo_, with the Commission on board, passed up
the Amazon to the mouth of the Ucayali river, up the Ucayali past the
rapids of the "Devil's Leap," and entered the Tambo river. The Tambo
was found to be a narrow stream, full of rocks and rapids and not
practicable for navigation by steamers. When the steamer _Tambo_ could
ascend no higher, Tucker fitted out a small boat and pulled some
twenty miles farther up the river, but everywhere found such
obstructions as rendered it an impracticable route to the interior. It
is, perhaps, to be regretted th