SEPTEMBER 3, 1897.] 
origin. Where long continental slopes 
descend beneath the ocean at a steeper 
gradient than 1 in 35, slipsand earthquakes 
of this kind may be expected. The western 
boundary of the Tuscarora deep, in the 
North Pacific, is a source of many earth- 
quakes, among them the destructive disturb- 
ance of June 15, 1896. ‘There Milne 
infers ‘sudden sub-oceanic changes along 
the basal frontier of a continent, the mag- 
nitude of which it is difficult to estimate.’ 
Certain ‘ unfelt earthquakes’ recognized by 
the horizontal pendulum are recorded at 
widely separated stations, ‘and it is fair to 
assume that in these instances the whole 
world has been shaken.’ Their source 
cannot have been on any land, for then 
they must have been observed in the or- 
dinary manner; they are therefore ascribed 
to submarine movements. 
If the occurrence of sub-oceanic slides be 
verified, they afford a new argument for 
the permanence of continents and oceans ; 
for nowhere do the sedimentary strata of 
the continents exhibit so confused a struc- 
ture as must be thus produced along the 
slope and basal frontier of a continental 
mass. 
W. M. Davis. 
HARVARD UNIVERSITY. 
CURRENT NOTES ON ANTHROPOLOGY. 
STONE IMPLEMENTS FROM THE POTOMAC DIS- 
TRICT. 
Proressor .Witt1am H. HotmeEs con- 
tributes to the Fifteenth Annual Report 
of the Bureau of Ethnology one of 
his excellent and beautiful papers, this 
one on the ‘Stone Implements of the 
Potomac Chesapeake Tidewater Province,’ 
152 pages, with 104 full-page plates, and 
36 figures in the text. The geograph- 
ical and geological relations of the area 
are carefully explained, and the arte- 
facts themselves are examined under the 
classification of flaked, battered or abraded, 
SCIEN CE. 309 
and incised or cut stone implements and 
utensils. Thetypical forms and characters 
are illustrated, the processes of manufacture 
are set forth, and the extensive quarries 
where the material was obtained are de- 
scribed. 
The conclusion of the author, after years 
of patient research with reference to the 
antiquity of man’s work in this region, 
may be given in his own words (p. 146): 
“The art remains preserved to our time 
indicate the prevalence of extremely simple 
conditions of life throughout the past, and 
exhibit no features at variance with those 
characterizing the historic occupancy.” So 
that we shall have to go elsewhere to find 
“paleolithic man.’ 
ETHNOGRAPHY OF THE CALCHAQUIS. 
In Scrence, May 7th, I referred to some 
interesting art remains discovered by Am- 
brosetti in the territory of the ancient Cal- 
chaquis. Ethnographers have been unable 
to identify these with any modern tribe (see 
‘The American Race,’ p. 319). The latest 
effort is by Dr. Ten Kate. He availed him- 
self of a series of skeletons in the Museo de 
La Plata, exhumed from old graves in Cal- 
chaqui territory. Some were deformed, 
and of the normal there were a number of 
types; but the characteristic features were 
extreme brachycephaly and a short stature. 
In both respects these ancient differed from 
the modern natives of the place. Looking 
around for similarities, Dr. Ten Kate found 
them among the Huarpes of the province 
of La Rioja, where skeletons with the same 
traits occur. He does not, however, iden- 
tify them with the Huarpes (or Allentiacs), 
who are probably related to the Chaco 
tribes, but rather with the Araucanian 
stock, so far as one can judge from the 
synopsis of his conclusions in the Central- 
blatt fir Anthropologie. 
These analogies are not borne out by the 
linguistic evidence of the proper names in 
