NOVEMBER 8, 1899.] 
tion, or by communication or contact. If 
we accept the doctrine of the unity of the 
human species, we are forced to admit con- 
tact between peoples of different countries 
as accounting for the differences in their 
cultures rather than to account for it by 
the similarity of their respective thoughts. 
The race could not have been perpetuated, 
the new peoples could not have been born, 
the different countries would never have 
been peopled, whether separated or not, 
except on the theory of migration and com- 
munication or contact. It is only by con- 
tact that subsequent generations could have 
appeared, and only by migration that they 
could have become separated. If the spread 
of culture by migration is denied, the 
spread of the race must also be denied. 
The two things, similarity of race and of 
culture, stand on the same foundation. 
This foundation is migration, communica- 
tion, contact. 
Monuments, Burial Mounds and Tumult. 
Nothing has yet been said as to the monu- 
ments or art of prehistoric man. The art 
is sufficiently explained in my work on 
‘Prehistoric Art’; published in the re- 
port of the U. S. National Museum for 
1896, pp. 325-664, with 74 plates and 325 
text figures, and I need not dwell further 
on it. 
The monuments of prehistoric times are 
curious and strange. Whatever country 
“we may consider, they excite our wonder 
and admiration. The ingenuity, invention, 
thought and general savoir faire of the pre- 
historic man as shown in his industries, and 
the taste and genius shown in his art, all 
pale before his ability as an architect and 
builder. 
The principal monuments made by pre- 
historic man in most countries and times 
seems to have been funereal. The paleo- 
lithic man made no monuments, and it is 
doubtful if he habitually buried his dead. 
SCIENCE 
647 
But the neolithic man expended his en- 
ergies and powers in the erection of tombs 
and monuments intended to protect, and 
possibly to commemorate, his dead. 
Dolmens were chambers of stone in which 
the dead bodies were placed. In Europe 
mounds were frequently, and in America 
were always erected over such burials, and 
these stand as testimonials of the affection- 
ate regard with which the barbarian of pre- 
historic, whether in Europe or America, re- 
garded his dead. 
Although these monuments may not be 
the same in the details of their construction 
in both countries, they are all founded on 
the same principle of regard for the dead. 
This remark applies equally to Europe as 
to America. The burial tumuli and dol- 
mens of Lozére and Morbihan in France do 
not contain a greater number of bodies than 
those of the Turner, or the Hopewell group 
in Ohio ; while for size, extent and compli- 
cated design and perfection of execution, 
those we are to see during this session at 
Newark, Circleville and in the Scioto Valley 
will equal any throughout Europe. 
The military monuments, fortresses, em- 
bankments, squares, circles and breastworks 
of the two countries tell the same story. 
They were built in both countries, some- 
times of stone and again of earth, and show 
in every quarter an amount of engineering 
skill. The parallel lines at Marietta and 
Piketon, the circles and octagons on the 
State camp-ground at Newark, in the Scioto 
Valley, and at Portsmouth, Kentucky, have 
their counterparts in the extensive earth- 
works of protective ditch and embankment 
of Camp Peu-Richard at Saintes (Charente); 
while the fortresses and camps of stone or 
earth of forts Ancient or Hill, or opposite 
Bournemouth, are but the complements of 
Camp de la Malle (Alps Maritimes) or the 
great Gaulish fortress of Uxellodenum on 
the Dordogne. 
Other monuments in Europe occupy a 
