Dear Dr. Boli: I find myself facing a difficult theoretical problem, and I am at a loss as to how to arrive at the solution. If the distance between Pittsburgh and Chicago is 500 miles, and a train sets off from Chicago at 45 miles per hour, and another sets off from Pittsburgh at 50 miles per hour, when will they meet? —Sincerely, A Student of Mathematics in a Local Secondary School.

Dear Sir or Madam: They will not meet. You neglected to mention that the train from Pittsburgh is headed for Philadelphia, whereas the train from Chicago is headed for Milwaukee. Without this information the problem is, of course, insoluble. With the proper information, however, it becomes trivially easy.


On This Day in History.

ON THIS DAY in 1857, the famous tea clipper Pertinacious was wrecked in a ferocious gale just outside Zanesville, Ohio. To this day no one knows how it got there.