I broke a bone a couple of weeks ago.

Not just any bone, but a 72- million-year-old vertebra of an Edmontosaurus regalis.

I was mortified. I froze in my tracks. Dark thoughts raced through my mind: This is it! No more columns! You're in deeeeeeeeeep doo-doo!

Suddenly, someone took the pieces from my hand and coolly said, "Don't worry. We'll just glue it back together."

Being an amateur archaeologist (even for a few hours) is tough. And lots of fun.

Here I was in the PaleoLab of the Carnegie Museum of Natural History, the guest of scientific preparators Allen Shaw (also the PaleoLab manager) and Dan Pickering, getting the chance to do what only the likes of scientists and Spielbergs do -- fuss with fossils, dust off dinosaurs.

Allen and Dan are in the process of assembling an Edmontosaurus regalis, the dinosaur that will eventually be put on display as "dinner" for the museum's popular Tyrannosaurus rex when the T. Rex is put back on display in June. The guys have already spent about four weeks on the project and have about eight more to go. The evidence of their work is everywhere: Under a plastic tent is the thigh bone of the beast; in a sand box are more vertebrae awaiting assemblage. I chuckle when I see that the "sandbags" holding the fossils in place are latex rubber gloves filled with sand.

The Edmontosaurus regalis has no nickname; when gently nudged, Dan suggests "Ed." I figure since I have been intimate with him, I should call him "Mr. Ed."

Allen hands me what looks (and sounds) strangely like an oversized dentist drill. For a sadistic second, I imagine getting back at all those childhood dentists who scared me to the bone. But I am here to work, not overwork my imagination. The tool is an airscrib; this is used to "chisel" off the dried dirt that, over the millions of centuries, has actually become thick limestone, coating the fossilized bone underneath. Zzzzzzzzzz! Off flies a chunk. Zzzzzzzzzz! There goes more. I drill carefully, dirt and dust and fossilized rock flying about when not being sucked up by a nearby vacuum. Occasionally the airscrib throbs, signaling that I have gone as far as I can and have hit actual dino bone. When Allen sees my success, he hands me a larger airscrib. Zzzzzzzzzz! More dirt. Zzzzzzzzzz! More limestone. I am the Wizard of Zzzzzzzzzz!

Then it's time to play with the putty -- polymer in various shades that are scooped out of plastic pails and used to fill the bones' cracks and holes. I scoop out some brown putty and get ready to work on another piece of Mr. Ed's tail. It's High-Tech Arts and Crafts made easy: I simply fill the cracks with putty, then dip my fingers in water and rub off the excess. Fill. Dip. Rub. Fill. Dip. Rub. Dan shares an age-old secret with me: Using a crumpled paper towel -- the older the better -- gives the putty a distressed look, and the actual bone and the repair get a uniform look. I pull a well-worn wad and briskly rub it across the polymer. Instant aging! I remind myself to someday share the secret with Martha Stewart.

It's time for Mr. Ed to get a rest.

And time for me to go.

I scoop up a small pile of the fossilized dirt as a souvenir, and I give Mr. Ed a pat on one of his many disjointed vertebrae. "Make no bones about it, buddy," I silently tell my prehistoric pal, "you look good for your age."

And I have the dirt to prove it.