Twenty Thousand Leagues Under the Seas by Jules Verne

Three seconds before the arrival of J. B. Hobson's letter I no more thought of pursuing the unicorn than of attempting the passage of the North Sea. Three seconds after reading the letter of the honourable Secretary of Marine, I felt that my true vocation, the sole end of my life, was to chase this disturbing monster and purge it from the world.

But I had just returned from a fatiguing journey, weary and longing for repose. I aspired to nothing more than again seeing my country, my friends, my little lodging by the Jardin des Plantes, my dear and precious collections--but nothing could keep me back! I forgot all--fatigue, friends and collections--and accepted without hesitation the offer of the American Government.