Both young engineers nearly lost their lives in Nevada, and met with many strenuous situations.

Their sole idea in pushing their mine forward to success was that the money so earned would enable them to further their greatest ambition; they longed to have their own engineering offices.

In the end, their mine, which the young engineers had named "The Ambition," proved a success.

Thereupon they left their mining partner, Jim Ferrers, in charge and went east to open their offices.
We next found the young engineers engaged to the south of the United States border.

These adventures were fully set forth in the preceding volume in this series, entitled "_The Young Engineers in Mexico_." Tom and Harry, engaged to solve some problems in a great Mexican mine, found themselves the intended tools of a pair of mine swindlers of wealth and influence.
From their first realization of the swindle Tom and Harry, even in the face of threats of assured death, held out for an honest course.