this among certain of these northern tribes, but, save for occasional
examples, it is limited at best. Dr. Franz Boas, who has travelled
extensively among the Eskimos, and whose observations are always of the
most accurate nature, once told the author that he never met an Eskimo who
could count above 15. Their numerals actually do extend much higher; and a
stray numeral of Danish origin is now and then met with, showing that the
more intelligent among them are able to comprehend numbers of much greater
magnitude than this. But as Dr. Boas was engaged in active work among them
for three years, we may conclude that the Eskimo has an arithmetic but
little more extended than that which sufficed for the Australians and the
forest tribes of Brazil. Early Russian explorers among the northern tribes
of Siberia noticed the same difficulty in ordinary, every-day reckoning
among the natives. At first thought we might, then, state it as a general
law that those races which are lowest in the scale of civilization, have
the feeblest number sense also; or in other words, the least possible power
of grasping the abstract idea of number.

But to this law there are many and important exceptions. The concurrent
testimony of explorers seems to be that savage races possess, in the great
majority of cases, the ability to count at least as high as 10. This limit
is often extended to 20, and not infrequently to 100. Again, we find 1000
as the limit; or perhaps 10,000; and sometimes the savage carries his
number system on into the hundreds of thousands or millions. Indeed, the
high limit to which some savage races carry their numeration is far more
worthy of remark than the entire absence of the number sense exhibited by
others of apparently equal intelligence. If the life of any tribe is such
as to induce trade and barter with their neighbours, a considerable
quickness in reckoning will be developed among them. Otherwise this power
will remain dormant because there is but little in the ordinary life of
primitive man to call for its exercise.