ed the conclusion then arrived at.

I experimented with the two groups of 20 pupils each. Neither knew any
method of dealing with dates and numbers. The first group had had no
training in In., Ex., and Con.; the second group had been well practised
in those laws. I then gave each member of each group several very
difficult cases of dates and numbers to be memorised--one example
containing 24 figures. To save time and space in exposition, I have
heretofore only mentioned 12 figures, or the half of the amount. All of
the first group failed except one. He, however, could not memorise the
24 figures. All of the second group handled all the new examples with
success, and only two of them met with much difficulty in dealing with
the 24 figures.

Since this decisive experiment, I have heartily recommended the method
of finding relations amongst the numbers themselves, to all who are
proficient in the use of In., Ex., and Con.

The example of 24 figures must conclude this exposition. They represent
respectively the number of the day of the month in which the first
Saturday in each month falls in 1895 and 1896. To one without practice
in applying analysis to figures, there seems no hope of memorising this
long group of figures except by endless repetition. The 24 figures are

522641637527417426415375.

Yet reflect a moment and all will be clear. Divide the 24 figures into 2
groups of 12 figures each and number the first group, divided into four
sections, thus:--

(1) (2) (3) (4)
522, 641, 637, 527.

Now bring the first and fourth groups into relation, and you see at once
that the fourth group is larger than the first group by only _five_.
Bringing the _second_ group into relation with the _third_ group, we
find they differ only by _four_. Again: the third group is larger than
the fourth by 100 and by 10, that is 527 becomes 637, the seven alone
remaining steadfast. Beginning with the fourth group and passing to the
third group we have the fourth group with 110 added. The second group is
the third group with only four added, and the first group is the fourth
group with only five subtracted. Thinking out these relations you can
recall the groups as groups or the separate figures of each group or the
entire 12 figures either forwards or backwards--and you have achieved
this result by _Attention_ and _Thought_.

The other twelve figures are easily disposed of. They are 417426415375.
Divided into