CHAPTER I.
The Secret of the Gulf--Ulloa, 1539, One of the Captains of Cortes, Almost Solves it, but Turns Back without Discovering--Alarcon, 1540, Conquers.
In every country the great, rivers have presented attractive pathways for interior exploration--gateways for settlement.

Eventually they have grown to be highroads where the rich cargoes of development, profiting by favouring tides, floated to the outer world.

Man, during all his wanderings in the struggle for subsistence, has universally found them his friends and allies.

They have yielded to him as a conquering stranger; they have at last become for him foster-parents.

Their verdant banks have sheltered and protected him; their skies have smiled upon his crops.