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villages, they are irregular rings, which have only surrounded a single 
tent. 
At this period the pine was the common forest tree of Denmark ; and 
with it is found the cock of the woods, which feeds chiefly on pine buds. 
With the heaps occur tumuli, which have supplied numerous skeletons. 
The skulls are round, and nearly resemble those of the Laps, but have 
a very prominent ridge over the eyes, approximating them to the form 
figured in the Plate. The front teeth do not overlap, but meet as do 
those of the Greenlanders. The age of these makers of the shell mounds 
is probably much more recent than that of the people of the caves before 
mentioned, but it still was, even measured by a natural history estimate, 
a very ancient period, for when these Danes ceased to work flint we find the 
pine-trees disappearing. These trees were succeeded by oaks, and with them 
came a race with differently formed heads, workers in bronze. And in 
their turn the oak-trees die away, and are replaced by beeches ; and then 
comes yet another race of men, workers in iron, — a people whose tumuli 
tell of a long national existence before the Christian period. 
The same divisions of time into the ages of stone, bronze, and iron, 
which were long ago well defined by ethnologists, have of late received 
excellent illustration in the explorations of the Swiss lakes. The bones 
of the men of the stone period as yet found are so few, that all we can 
say of their forms is that the people had round skulls. The tribes lived in 
villages on the borders of the lakes, and formed their habitations by 
driving piles into the bed of the lake. The trees vary in diameter from 
3 to 9 inches, and in length from 15 to 30 feet, and some settlements have 
as many as 40,000. They penetrate into the mud about 5 to 11 feet, and 
have the lower end rudely pointed by the action of fire, and by stone 
hatchets. It is not quite certain whether the dwellings were perched on 
the top of these piles, or whether they floated on the water between them, 
though the latter condition is the more likely one. The cabins were built 
on a platform consisting of five layers of trees bound together by in- 
terlacing branches and clay. These dwellings appear to have been burnt, 
and it has so hardened their interior lining of clay, that it has been con- 
cluded from large pieces found that they were circular, and from 10 to 15 
feet wide. All the species of animals which occur in the lake deposits, 
excepting the Bos primigenius, (the wild bull now extinct), are still found 
in various parts of Europe, though many have long since disappeared from 
Switzerland. Imbedded with them are a multitude of fashioned flints and 
other stones : chiefly hammers, axes, knives, saws, lance-heads, arrow- 
heads, and corn-crushers. A rude kind of pottery occurs. A few domestic 
animals are found ; and another indication of a civilization in wheaten 
cakes, and dried apples, and pears. 
This stone age is probably of the same date as that of Denmark ; the 
periods which succeed it are not so broadly distinguished from it as are 
those of the latter country, for the people still continued to build the 
“pile works” through the “bronze” period into the early part of the age 
of iron. Most of the remains are now covered by several feet of peat. 
We are informed on good authority, that a collector at Woodbridge 
