"That will reduce some of these amounts about one-tenth," he said to himself. "In our physics work in college, good soils generally lost about ten per cent. in weight by ignition, even after all hygroscopic moisture had been expelled; but these very poor soils haven't much to lose, I guess. They surely contain no carbonates and very little organic matter, although they may contain some combined water." CHAPTER XXIV THE NATION'S CAPITOL PERCY spent three days in Washington. "If I lived here long," he wrote his mother, "I think I should become as optimistic as the Secretary of Agriculture, even though the total produce of the original thirteen states should supply a still smaller fraction of the necessities of life required by their population. The Congressional Library is by far the finest structure I have ever seen. I cannot help feeling proud that I am an American when I walk through its halls and look upon the portraits of the great men who helped to make our country truly great. "As I shook hands with the President of the United States at one of his public receptions held in the 'East Room' of the White House, I wondered if there was another country on the earth where the humblest subject could thus come face to face with the head of a mighty nation. In the Treasury Building I was permitted to join a small party of some distinction and shared with each of them the privilege of holding in my hands for a moment eight million dollars in government bonds. "I have visited many of the great buildings, the Capitol, of course, and Washington's monument, which rises to a height of 555 feet above the surrounding land, or practically 600 feet above low-water level in the Potomac. There are many smaller monuments erected in honor of American heroes in various squares, circles, and parks throughout the City. "The zoological garden took a full half-day, and I could have spent a much longer time there. They told me of a frightful occurrence that happened only last week. In a pool of water a very large alligator is kept confined by a low stout iron fence. A negro woman was leaning over the fence holding her baby in her arms and looking at the monster who seemed to be asleep; when, without a moment's warning, he thrust himself half out of the water and snapped the baby from her arms, swallowing it at one gulp as he settled back into the water. I fear the report is true enough, for they have made the fence higher in a very temporary manner, and I heard it mentioned by a dozen or more. "I leave Washington by boat at five o'clock this afternoon, and I expect to land at Leonardtown, St. Mary county, Maryland, about six o'clock in the morning, when the boat will be ready to leave that port. It is a freight boat and stops for hours at large towns.