w with a stick," he said; "it's a kind of a magic wand. Ever
talk with a civil engineer?"

"Believe me," I said, "the only civil engineer I ever talked with, did
most of the talking. He wouldn't let us play ball in his lot. He was an
uncivil engineer, that's what _he_ was."

Bert said, "Well, there was a civil engineer here with a troop from out
west somewhere. He was a scoutmaster. He took me on a couple of good
hikes. We found some turtle shells over through there, a little farther
along, and when he took a squint at the land he saw how a little
valley, all grown up with weeds and brush, ran along east and west. He
said that was where the creek once flowed and it didn't come within a
mile of the lake. Savvy? The place where the lake is now used to be
Bowl Valley. When the creek changed its bed and cut through a couple of
miles south, it just filled up Bowl Valley and there you are--Black
Lake. Presto chango! Funny how old Dame Nature changes her mind now and
then."

"That's just the way it is with girls," I said.

Bert said, "Well, and that scoutmaster said she'd be changing her mind
again some day, too. He said the topography around here is pretty
shaky--whatever that means."

"Oh, boy," I said, "break it to me gently. Do you mean that some fine
day we'll wake up and find Black Lake has sneaked off?"

"That's just about it," he said.

"Do you call that fair and square?" I asked; "after Mr. Temple bought
the lake and gave it to Temple Camp. Believe me, it _ought_ to be
called Black Lake; it isn't very white, that's one sure thing."

"That may not happen for a thousand years," Bert said.

CHAPTER XXVII

TELLS ABOUT HOW WE TRIED TO STOP IT RAINING

Jumping jiminy! That was a new one on _me_. Lakes moving around like
people that live in flats--_good night_! And where would Temple Camp
be, I'd like to know? And just after we paid four dollars and eighteen
cents to put up a springboard.

"If you wouldn't mind," I said, "I'd like to know how that could
happen. Because if it's going away I'm going to stalk it."

"Do you know what erosion is?" he said.

"Not guilty," I told him.

"Well," he said, "it's earth being eaten away, kind of."

"By who?" I asked, "he must have some appetite."

"By the water," he said; "that's what causes changes in topography."

"All right," I said, "I'll take your word for it. But will the lake be
there when we get back, because I've got some eel lines out?"

He said, "Oh