“Meantime, Uncle George, I suppose you had found the Bone Cabin quarry,” said the boy, anxious to bring his uncle back to the story of the discovery.
“We first found that quarry in the autumn of the year we began work on the Como Bluffs,” the professor replied. “One of our fellows was doing a little prospecting over the plains, as we felt we had exhausted the Como Bluffs specimens that had been exposed so far. Now, if you remember, Perry, as we rode out here this afternoon, we sighted the Laramie Mountains and the Freeze Out Hills and I pointed out to you that they were quite recent in origin. As those ranges were uplifted, they crushed together the surface of the level plains and crumpled them into rock waves. Erosion cut away the tops of those waves and exposed the rock at the edges, though, of course, the lower parts of these rock waves are still underground and it will take the erosion of many centuries to expose them. The bone-hunters of the future will find more treasures waiting for them on the Laramie Plains, just as we have done.
“You remember, Perry, I showed you the irregularities of the bone layer. At the place where you started up that prong-horn antelope to-day, the bone layer was level, and that little gully where you retrieved that sage chicken you shot, just before dinner, was the trough of one of those rock waves. The Laramie Plains are like a huge graveyard of the giant saurians which has been crumpled like a sheet of paper. So, when we had almost finished with the Como Bluffs, we decided to prospect across the plains, watching carefully for each place that might be the top of one of these waves, and therefore might be an exposure of the fossil-bearing fresh-water rock.
“As the second in command of our party was riding over the plains, keeping a sharp lookout for the characteristic lie of the land, he noticed a little hillock. Not being a part of the usual wave formation, it did not strike him forcibly, but, in riding past, he noticed a number of brownish masses that looked like sandstone concretions. Brown sandstone is not plentiful in that region, so he looked a little more closely.
“Suddenly he pulled up with a jerk. There, at least, was something that was not sandstone! A less experienced eye would have passed the boulder by, but the Museum expert was too keen a man not to have quick perception. Another, and another and yet another! He hopped off his pony, dropped the reins, and came to the hillock.
“The entire mound was made of dinosaur bones!
“All the dark-brown boulders were the remains of ponderous fossils which had slowly washed out from a great dinosaur bed beneath. The bones had been so thickly strewn that they had held the soil together against erosion. The explorer climbed the little hillock, and there, near the top, was the abandoned dugout foundation of a shanty that some Mexican herder had built there many a year ago. It was a shallow cellar, only a few feet deep.
“The foundation was lined with a wall of fossil bones! These huge petrified blocks which the herder had only thought of as stones and used as a base for his shanty, were treasures that are now of incalculable value to the scientific world. To the trained eye, this hillock was like a sign-post slowly erected by Nature during millions of years to point the way to the great cemetery below where the most gigantic of her children lay buried.
“It was in the late spring of next year that I came on the scene. The hillock was a mass of glowing color. Wild flowers were blooming everywhere. The cacti were in full blossom, and the dwarf bushes of the desert were in the few weeks of their greenness. Half-hidden amid the flowers and the cacti were these brown boulders which had been found to be bones.
“All the three great kinds of dinosaurs were there, Perry. The bones of the huge Brontosaurus and Camarasaurus lay beneath that hillock of the great army of Amphibious Dinosaurs, those monsters with blunt pointed teeth and blunt claw, with limbs and feet like elephants, unarmored five toed, with long neck and small head; only the most tremendous of them, the Brachiosaurus, was missing. These Amphibious Dinosaurs were the largest creatures that ever trod the world, Perry, and their bulk was too great for them to have lived any other than a marsh life, when the buoyancy of the water in part sustained the weight of their enormous bodies.