Miss Katherine Mayo comes of Mayflower stock, but her birthplace was Ridgway, Pennsylvania. She was educated in private schools at Boston and Cambridge, Mass. Her earliest literary work to appear in print was a series of articles describing travels in Norway, followed by another series on Colonial American topics, written for the New York _Evening Post_. Later, during a residence in Dutch Guiana, South America, she wrote for the _Atlantic Monthly_ some interesting sketches of the natives of Surinam. After this came three years wholly devoted to historic research. The work, however, that first attracted wide attention was a history of the Pennsylvania State Police, published in 1917, under the title of _Justice To All_. This history gives the complete story of the famous Mounted Police of Pennsylvania, illustrated with a mass of accurate narrative and re-enforced with statistics. The occasion of its writing was a personal experience--the cold-blooded murder of Sam Howell, a fine young American workingman, a carpenter by trade, near Miss Mayo's country home in New York. The circumstances of this murder could not have been more skilfully arranged had they been specially designed to illustrate the weakness and folly of the ancient, out-grown engine to which most states in the Union, even yet, look for the enforcement of their laws in rural parts. Sam Howell, carrying the pay roll on pay-day morning, gave his life for his honor as gallantly as any soldier in any war. He was shot down, at arm's length range, by four highway men, to whom, though himself unarmed, he would not surrender his trust. Sheriff, deputy sheriffs, constables, and some seventy-five fellow laborers available as sheriff's posse spent hours within a few hundred feet of the little wood in which the four murderers were known to be hiding, but no arrest was made and the murderers are to-day still at large. "You will have forgotten all this in a month's time," said Howell's fellow-workmen an hour after the tragedy, to Miss Mayo and her friend Miss Newell, owner of the estate, on the scene. "Sam was only a laboring man, like ourselves. We, none of us, have any protection when we work in country parts." The remark sounded bitter indeed. But investigation proved it, in principle, only too true. Sam Howell had not been the first, by many hundreds, to give his life because the State had no real means to make her law revered. And punishment for such crimes had been rare. Sam Howell, however, was not to be forgotten, neither was his sacrifice to be vain. From his blood, shed unseen, in the obscurity of a quiet country lane, was to spring a great movement, taking effect first in the state in which he died, and spreading through the Union.