Dinosaurs (the word means terrible lizard, from the Greek
Deinos Sauros) varied in size with the largest reaching the
weight of 30 tons and an overall length of ninety feet.
The Dinosaurs that left tracks in New England were up to
thirty-six feet long and weighed up to twelve or fifteen tons.
The footprints of several of these Dinosaurs are in the Stanley
Park exhibit. There is a series of fifteen-inch prints, another
consecutive series of twelve-inch prints and then there are
smaller miscellaneous tracks. There are three seven-inch prints
made by the same Dinosaur and the length of the stride indicates
that the Dinosaur was running across the mud flats.
The large prints were probably made by a type of Dinosaur
known as Eubrontes. The small prints were left by a type called
Grallator. Both Eubontes and Grallator were bipeds.
In the same section of stone, which is 28 inches wide by
18 feet long, you will find ripple marks and evidence of fossil
wood. These are indicated on the diagram. Fossil wood is indicative
of vegetation during the age of the Dinosaur. Ripple marks
were formed by the wind blowing over shallow water.
The series of tracks came from a quarry discovered and owned
by Carlton S. Nash of South Hadley, Massachusetts. In talking
of the footprints, Mr. Nash says, "The tracks were made
by Dinosaurs on mud flats probably of clayish iron content
texture millions of years ago. During the Ice Age, these mud
flats were covered with glacial deposits from the North and
slowly hardened into sandstone. Eventually from the earth's
warping, volcanic action and erosion, these petrified prints
were exposed. Thus the cycle was complete.
When a layer of tracks is exposed, the shale is cut with
special saws, and chisels are used to split the shale and
remove the track intact. Great care is taken not only to avoid
breaking the tracks that are to be removed, but also to avoid
damaging the tracks in layers not yet exposed. Even the toenail
marks are saved. Mr. Nash has excavated over twenty-nine layers
of tracks and there is no indication as to how many more layers
there may be.
Two types of tracks are found. Those in Stanely Park are
impressions. Mud flowing into the impressions hardened, and
consequently when the layers are separated a raised track
is also obtained. Both types of track are equally valued.
One track at the end of the display has been left available
for visitors who would like to have their picture taken standing
where the Dinosaur once stood many millions of years ago.
The quarry where these tracks were found is open to visitors.
There one may see layer upon layer of prehistoric prints made
long before the dawn of man. It is fascinating to watch the
quarrying operation and to realize that the prints being uncovered
are those of reptiles that once roamed this entire valley.
At the quarry, there is preserved one large section of stone
which shows the haunch and tail mark where a Dinosaur sat
down to rest and there is a building made of Dinosaur prints.
Single tracks or large sections containing many prints may
be purchased at the quarry which is reported to be the largest
and oldest of its kind.
If you would like to read a detailed description of the age
of the Dinosaur, with many illustrations, you will find a
very comprehensive article in LIFE magazine, September 7,
1953, Pages 62 to 69.