The mounted brontosaur in the American Museum of Natural History, New York, will enable one better to appreciate the size of these giants of the ancient world. This typical specimen, though not the largest found, is sixty-seven feet long and stands fifteen and one-half feet high. Its neck measures thirty feet in length and its tail eighteen. The body weighed about ninety tons. This huge fossil, enclosed in its stone matrix, was sent from the quarry to the museum. After it had been received two men were employed constantly for nearly two and one-half years in removing the matrix, repairing, and mounting the fossil. Let us turn now to the burying ground of a giant forest. Long, long years ago, before man appeared on the earth, an inland sea occupied what is now the northeastern part of Arizona. It was a sea bordered with sandstone and surrounded by coniferous forests, where stately trees nodded in the breezes. At length there came a great change. The rim of the basin gave way, and the great volume of water, freed from restraint, overwhelmed the forest with earthy material, prostrating and burying it deep beneath the flood of sand. In time the woody structure disappeared, and was replaced by beautifully stained opal and agate. Again, in the lapse of time the old forest bed was once more lifted above its former level, forming a mesa, or plateau, of considerable extent. During subsequent ages, the elements scarred and furrowed the plateau, forming canyons, gulches, valleys, and buttes, thus revealing in part this ancient forest. Could these dead trees but talk, how interesting would be their story! We can read their history but imperfectly by examining the mutilated breast of Mother Earth, in and on which lie these mute stone trees, dead yet made more beautiful through their transformation. [Illustration: _Property of the American Museum of Natural History_ The Allosaurus (carnivorous dinosaur)] This region is called the "Petrified Forest," or "Chalcedony Park." It is about one hundred square miles in extent, and is visited annually by thousands of people from all parts of the world. On account of its strange geological character it is of special interest to the scientist. Let us make a brief trip to this wonderful stone forest. We take light hand-baggage and board a Santa Fe train. The railway passes near the most interesting part of the forest, and we change cars before entering Arizona in order to take this line. The railway officials have made a station at Adamana, six miles from the edge of the forest, in order to accommodate the travelling public. We leave the train here and procure a team to carry us to the forest. Unless informed of what is to be seen one is apt to be greatly disappointed. One's idea of a forest is usually that of a timber-covered area in which the trees stand erect, with outspreading branches; but we look in vain for a standing tree, or even a stump that is erect.