"Quite another matter altogether," McPhearson said. "Immediately the Athenians, who had invented the device, put it to work and proceeded to limit the length of time speakers should talk in their courts of justice. Evidently then, as now, men were fond of making speeches and arguing and became so fascinated by hearing themselves talk that they forgot to stop. Now here was something that would put a check on them. When a case came up for a hearing, the accuser was allowed the first jar of water, the accused the second, and the judge the third. Stationed beside the clepsydra was a special officer whose duty it was not only to fill it but to stop the flow whenever a speaker was interrupted, thereby making certain he was not cheated of any of the time due him." "A bully scheme!" Christopher remarked. "It worked," McPhearson answered. "With such strict rules you may be sure there was none of the thing the Athenians termed 'babbling.' Men guarded their words like jewels when each word meant the dripping away of his allotted time." "And did people continue to use this water clock?" "Yes, for quite a time, but after a while they began to find fault with it. In the first place they noticed that when the vessel was full the greater pressure of water caused it to drip much faster than when there was not much in it. This they had not considered before, and the discovery forced them to attempt to improve it. This they did by concocting a sort of double jar. In the lower one there was a float that rose as the container filled; and since the top one was constantly replenished, it kept the pressure in the bottom one uniform." "The best yet!" "Much the best. In fact it was a stride ahead from several standpoints, for although it could not really be termed a machine it nevertheless was a device that did for man something he would otherwise have had to do for himself, which is the aim of all machinery. In just that proportion he moved toward a civilization where artificial methods relieved him of his labor. Thus he advanced quite a distance from that primitive condition when he did everything with his hands toward his next state of fashioning tools that would do what he wished to do better and quicker; here was something which worked independently of him." "Why, so it was! I never thought before that man passed through those three stages," ejaculated Christopher with pleasure; "it makes our old forefathers twice as interesting, doesn't it?" "Three times as interesting," the Scotchman laughingly responded. "Facts make very delightful stories, if you fasten them together. Scattered, unrelated information is both dry and worthless. It is only when linked up in the chain of history that it becomes interesting and valuable." "The trouble with me is I never know where the things I learn belong," observed the lad soberly. "It's like fitting pieces into a puzzle when you've no notion what picture you are making."