INTRODUCTION 
THE old-time question as to what knowledge is of most worth 
is forever being asked anew, while the answers are as varying as 
are the ideas and experiences of those to whom the query is pro- 
pounded. It belongs to that class of questions that cannot be 
answered in a dogmatic or categorical fashion, and yet those 
engaged in teaching must meet the question fairly and dispose of 
it in some practical manner. Speaking generally, we may say that 
that knowledge which makes us most effective and useful as citi- 
zens and at the same time enables us to appreciate and understand 
the part of the world with which we are likely to come into the 
closest, contact is of the most worth. 
We are not to understand from this that the useful citizen is 
he only who can produce most abundantly of material things; 
nor that our appreciation and understanding should not extend 
to the finer and more spiritual things of life. The point that should 
be kept clear is that the major part of one’s education should center 
about the things that will be of direct value and interest in the 
life of the individual. Nor should he be compelled to go outside 
the schools to obtain all the knowledge and skill that will be de- 
manded in later years. 
The realization of this fact by the more progressive educators 
has led to the production of a type of school literature that we 
scarcely hoped for twenty years ago. Many of these publications 
are designed to be used wholly as textbooks by special students; 
while others, of which the present work is an example, are well 
suited for school use and for general reading by young and old 
alike. The author has succeeded in bringing together within a 
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