Skylark (series)
Skylark is a science fiction/space opera series by the late E. E. "Doc" Smith. The first book The Skylark of Space (first published in Amazing Stories in 1928) is revolutionary in the genre, in which a scientist discovers a space-drive, builds a starship, and flies off with three companions to encounter alien civilizations and fight a larger-than-life villain.
The Skylark of Space was the first of a series which continued through 4 books -- Skylark Three and Skylark of Valeron written during the 1930s, and Skylark DuQuesne (DuQuesne is pronounced "Du Kane"), written much later in 1963. R. D. Mullen declared that "The great success of the stories was surely due first of all to the skill with which Smith mixed elements of the spy thriller and the western story (our hero is the fastest gun in space, our villain the second fastest) with those of the traditional cosmic voyage."