"Sounds like a kitten on a wager with a saucer of milk," laughed Tilly, frowning a little as she tried to adjust her sling more comfortably.
"Well, young ladies, we'll show you just what a lap is, if you'll come with us," promised Mr. Hartley; and with alacrity the girls expressed themselves as being quite ready to be shown.
On and on, mile after mile, down the great river swept the great ship until Forts Jackson and St. Philip were reached and left behind; then on and on for other miles to the narrow South Pass where on either side the Eads Jetties called forth exclamations of wonder.
"Well, you'd better 'ah' and 'um,'" laughed Genevieve. "They happen to be one of the greatest engineering feats in the world; that's all."
"How do you know that?" demanded Bertha.
"Don't worry her," cut in Tilly, with mock sympathy. "Poor thing! it's only a case of another guidebook, of course."
"Well, all is, just keep your weather eye open," laughed Genevieve, "for when we make the South Pass Lightship, then ho! for the—"
"Broad Atlantic," interposed Tilly.
"Well, not until you've passed through the little matter of the Gulf of Mexico," rejoined Genevieve; while a chorus of laughing voices jeered:
"Why, Tilly Mack, where's your geography?"