Thereupon they arrested him thinking that probably the man had been murdered and made away with, and that the boy had heard about it. But eventually he explained that he had seen the tracks of the man. He pointed out the tracks to them, and finally brought them to a place where the signs showed that the man had made a halt. Its hoof marks showed that it was lame, that is, one foot was not so deeply imprinted on the ground and did not take so long a pace as the other feet. That the rider was a soldier was shown by the track of his boot, which was an army boot.
Deduction is exactly like reading a book.
You would point out to him that a number of small signs on a page are letters. These letters when grouped form words. And words form sentences, and sentences give information. Similarly, a trained Scout will see little signs and tracks. He puts them together in his mind and quickly reads a meaning from them which an untrained man would never arrive at.