"'That the molecules composing all material substances are constantly in rapid motion, ricocheting against one another in the manner of a collection of billiard-balls suddenly stirred up, the speed of the air's components being about half that of a cannon ball, was the proof announced to-day from the University of Chicago as a further development of the experiments by Professor R. A. Threlkeld, which for the last year have been attracting the attention of scientists from all parts of the world. The absolute nature of the proof, upon which physicists all over the world have been working without result for several years, was assented to by Professor Pflüger, of Bonn University, Germany, who arrived in Chicago last Monday to witness the demonstration.'" He paused in his literal reading from the printed page. "I told you about Pflüger," he began. "Yes, some Dutchman," assented Rawn graciously. "They're great to dig." Halsey, being in the presence of the man whom he proposed making his father-in-law, was perforce polite, although indignant. He went on icily, with his reading, since he had begun it: "'The belief that the molecules of which all matter is composed are in a perpetual dance of motion has been held tentatively by scientists for several years, but, owing to the general inability to make any progress in proving it, considerable skepticism has developed among the physicists of several of the leading scientific nations. It was generally known as the kinetic theory. Professor Threlkeld's proof is a further development of his experiments, showing electricity to be a definite substance, which were announced last year and were pronounced the most important discovery concerning the nature of electricity since Benjamin Franklin. "'The simple expedient of performing his experiments in almost a complete vacuum--a method which had not occurred to scientists before--was given by Professor Threlkeld as the foundation stone of his discovery. Minute drops of oil, sprayed into a vacuum chamber, one side of which is of glass, demonstrate by their own motions the truth of the theory. "'Surrounded by the ordinary amount of air, the oil drops are bombarded by moving air molecules in so many thousand places at once that their motion is so rapid as to be invisible. With few molecules of air surrounding them, the drops are driven back and forth as though being used as a punching-bag. "'By reference to his previous experiments with drops of oil bombarded by electrical ions, the motion of the oil drops has been found to be precisely the same, showing the cause of the motion to be similar in both cases.'" "That's all right," said John Rawn, "all very well as far as it goes, but it doesn't go far enough." III Halsey smiled. "Well, here's what the discoverer says about it," he commented. "I reckon that's plain, too, as far as it goes: