periods, and sufficient interest in them, to keep
very close track of the date. Failure to pass the test at the age of
10 or 11 years is a decidedly unfavorable sign, unless the error is very
slight.

The fact that normal adults are occasionally unable to give the day of
the month is no argument against the validity of the test, since the
system of tests is so constructed as to allow for accidental failures on
any particular test. As a matter of fact, very nearly 100 per cent of
normal 12-year-old children pass this test.

The unavoidable fault of the test is its lack of uniformity in
difficulty at different dates. It is easier for school children to give
the day of the week on Monday or Friday than on Tuesday, Wednesday, or
Thursday. Mistakes in giving the day of the month are less likely to
occur at the beginning or end of the month than at any other time, while
mistakes in naming the month are most likely to occur then.

It is interesting to compare the four parts of this test in regard to
difficulty. Binet and Bobertag both state that ability to name the year
comes last, but they give no figures. Our own data show that the four
parts of the test are of almost exactly the same difficulty and that
this is true at all ages.

IX, 2. ARRANGING FIVE WEIGHTS

Use the five weights, 3, 6, 9, 12, and 15 grams. Be sure that the
weights are identical in appearance. The weights may be made as
described under V, 1, or they may be purchased of C. H. Stoelting & Co.,
Chicago, Illinois. If no weights are at hand one of the alternative
tests may be substituted.

PROCEDURE. Place the five boxes on the table in an irregular group
before the child and say: "_See the boxes. They all look alike, don't
they? But they are not alike. Some of them are heavy, some are not quite
so heavy, and some are still lighter. No two weigh the same. Now, I want
you to find the heaviest one and place it here. Then find the one that
is just a little lighter and put it here. Then put the next lighter one
here, and the next lighter one here, and the lightest of all at this
end_ (pointing each time at the appropriate spot). _Do you understand?_"
Whatever the child answers, in order to make sure that he does
understand, we repeat the instructions thus: "_Remember now, that no two
weights are the same. Find the heaviest one and put it here, the next
heaviest here, and lighter, lighter, until you have the very lightest
here. Ready; go ahead._"

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