uced by these. Wagner is of
opinion _a priori_ that one hundred, the maximum co-efficient, must be
assigned to mathematics; in this case, we should get the following
ponogenic co-efficients in schools, for each subject:

Mathematics 100
Latin 91
Greek 90
Gymnastics 90
History and Geography 85
French and German 82
Natural History 80
Drawing, Religion 77

We may note the arbitrary and surprising manner in which such results
are established; nevertheless, in the name of "experimental science"
it is possible to make such deductions as the following:

"It would be interesting to enquire if the order of the
ponogenic co-efficients varies with the age of the children,
which would enable us to know on the one hand when the brain
is best fitted for the study of any particular subject and
when therefore it would be most judicious to make it
predominate in the program; on the other hand, it would help
us in the arrangement of the daily time-table; we should
take, if possible, the most fatiguing subjects at the
beginning of the day" (Claparede, _op. cit._).

Another order of recent researches is that made into the toxines
produced by fatigue; Weichardt succeeded in isolating these toxines,
and in fabricating anti-toxines with which he experimented
successfully on rats. The experiments were also repeated in a clinic.
With regard to the appearance of the toxines, it was found that they
were abundantly produced during the performance of "wearisome" work,
whereas there were only traces of them to be found when the work was
"interesting."

Throughout this science so packed with researches which give as their
result unsolved problems, we perceive that not one of the factors
taken into consideration can alleviate fatigue; interruption and
change of work merely aggravate it. The one means by which _surmenage_
(exhaustion due to overwork) can be eliminated is to make work
pleasant and interesting, to give joy in work rather than pain.

"The necessity of making education and instruction attractive
has been propounded by all pedagogists worthy of the name,
such as Fenelon, Rousseau, Pestalozzi, Herbart, and Spencer,"
says Claparede, "but it is still unrecognized in the everyday
practise of the schools" (_op. cit._).

"By co