What worried me most was to what end this tunnel was made.

Such vast labor had surely never been performed without adequate purpose.

Besides, completed, the passage was well cared for.

I met frequently in my blind groping with evidences of comparatively recent labor.

Yet for what purpose was it designed?
Where did it lead?
To my bewildered judgment the general trend appeared northward; but that would carry it directly across the broadest portion of the upper basin.