4. The classification and explanation of the result.

5. The extension of the knowledge gained by turning it to investigations
suggested by what has already been learned.

6. The practical application of the knowledge gained.

II. In ordinary experiments for educational purposes the experimenter
follows in a general way in the footsteps of the original investigator.
There are the following elements to be considered:

1. The arrangement of conditions in general imitation of the original
investigator. This arrangement needs only to be general. For example, if
an original investigation were undertaken to determine the composition
of a metallic oxide, the metal and the oxygen would both be carefully
saved to be measured and weighed and fully tested. The ordinary
experiment would be considered successful if oxygen and the metal were
shown to result.

2. The careful consideration of what should happen.

3 The determination that the expected either does or does not happen,
with examination of reasons and elimination of disturbing causes in the
latter case.

4. The accepting as true of the classification and explanation already
given. Theories, explanations, and laws are thus accepted every day by
minds which could never have originated either them or the experiments
from which they were derived.