"I meant once to find out all about chronometers; but before I got started something interrupted me and I forgot it. I wasn't much interested in them anyhow, I'm afraid."
"And now you'd like a few points, eh?"
"Yes. I know I shall get a great deal better idea of them if you tell me," was the reply.
"If you weren't an American and I a Scotchman, I should say you were an Irishman," laughed his companion.
"Why?" demanded Christopher innocently.
"Because you sound as if you had kissed the Blarney Stone. Well, if you wish to learn about chronometers you have chosen a somewhat difficult subject. It leads pretty far, you see. However, I will do my best to give you at least a few facts about them. In the first place the earth actually revolves on its axis in twenty-three hours, fifty-six minutes, and four seconds. We commonly divide our day, however, into twenty-four hours and let it go at that. But astronomers reckon more accurately. They call our day the solar day and instead of having a clock with twelve figures on it as we do, they use one with twenty-four."
Christopher glanced up with a smile.
"Why be so fussy about things like minutes and seconds?"
"Because sometimes such things as minutes and seconds make a great deal of difference. You may remember that when we were talking of sundials I told you they were not exact timekeepers."
"I do remember."