present, and if
we had but the pelvic and leg bones of, say, a crow, we could, even
without ever seeing a crow, come pretty nearly drawing the picture of
how large a bird it is, and of what shape to be able to use such a
pelvis and such leg bones.

"So the men who reconstructed the Dinornis went at it. They set up the
pelvis and leg bones and then, with plaster or some substance, and by
working in proportion, they reconstructed the Dinornis, which is about
the shape of the ostrich or the extinct moa of New Zealand, only
larger. Here, I'll show you what I mean."

Sitting down on a pile of dirt and shale rock, excavated by some of his
workers, Professor Wright, on the back of an envelope, sketched the
pelvic and leg bones and then from them he drew dotted lines in the
shape of a big bird like an ostrich.

"You see how it is proportionately balanced," he remarked. "A bird
with that shape and size of leg would be about so tall--he could not be
much taller or larger or his legs would not have been able to carry him
around.

"Take, for instance, the giraffe. If you found some of their long,
thin leg bones, and had nothing else, and had never seen a giraffe,
what sort of a beast would you imagine had been carried around on those
legs?" he asked the boys.

"Well, a giraffe is about the only kind of a beast that could logically
walk on such long, thin legs," admitted Bud.

"And there you are," said the professor.

The boys were more interested than they had believed possible, and they
began to look forward eagerly to the time when some of the giant bones
might be uncovered.

"What gets me, though," said Dick, believing that while knowledge was
"on tap," he might as well get his fill, "what I can't understand is
how long ago they figure these things lived--I mean the Dinornis and
Dinosaurs," he added quickly, lest the professor resent his "pets"
being called "things."

"There's a good deal of guess-work about it," admitted the scientist.
"The question is often asked--how long ago did such monsters live. But
we are confronted with this difficulty. The least estimate put on the
age of the earth is ten million years. The longest is, perhaps, six
thousand million----"

"Six thousand million!" murmured Bud in an awed voice.

"And maybe more," said Professor Wright. "So you see it is pretty hard
to set any estimate on just when an animal lived who may have passed
away six billion years ago--it really isn't worth