Of Time and Texas

Twenty-eight-year-old William Nolan, another newcomer to the field, introduces us to the capricious Time Door of Professor C. Cydwick Ohms, guaranteed to solve the accumulated problems of the world of the year 2057.
Open the C. Cydwick Ohms Time Door, take but a single step, and—
In one fell swoop, declared Professor C. Cydwick Ohms, releasing a thin blue ribbon of pipe-smoke and rocking back on his heels, —I intend to solve the greatest problem facing mankind today. Colonizing the Polar Wastes was a messy and fruitless business. And the Enforced Birth Control Program couldn't be enforced. Overpopulation still remains the thorn in our side. Gentlemen— He paused to look each of the assembled reporters in the eye. —there is but one answer.
Mass annihilation? quavered a cub reporter.
Posh, boy! Certainly not! The professor bristled. The answer is—TIME!
Time?
Exactly, nodded Ohms. With a dramatic flourish he swept aside a red velvet drape—to reveal a tall structure of gleaming metal. As witness!
Golly, what's that thing? queried the cub.
This thing , replied the professor acidly, —is the C. Cydwick Ohms Time Door.
Whillikers, a Time Machine!
Not so, not so. Please , boy! A Time Machine, in the popular sense, is impossible. Wild fancy! However— The professor tapped the dottle from his pipe. —by a mathematically precise series of infinite calculations, I have developed the remarkable C. Cydwick Ohms Time Door. Open it, take but a single step—and, presto! The Past!
But, where in the past, Prof.?