IV PREFACE. 



this book, to prosecute his observations and- investigations in his 

 daily walks, and in his travels to different localities, far or near. 



I do not go largely into Mineralogy, but present enough of it sim- 

 ply to prepare the pupil for the study of Geology. Observe in this 

 connection the natural succession of subjects in the three parts of 

 this portion of my series. The Natural Philosophy properly pre- 

 cedes the Chemistry, and this latter the Mineralogy and Geology, 

 each study preparing the pupil to understand what comes after. It 

 should be remarked here that these studies, together with tljat of 

 Zoology, should precede the study of Physical Geography, for ac- 

 quaintance with them is absolutely essential to any thing like a full 

 knowledge of that science ; and yet it is very common to see class- 

 es wearily plodding through some book on Physical Geography, 

 who, from lack of this preparation, find most of it a terra incognita, 

 and know but little of what they have passed through when they ar- 

 rive at their journey's end. Let me not be understood to say that 

 this science should not be studied at all till after the pupil has gone 

 through with the studies that I have mentioned. It is only the full 

 consideration of it that should be delayed till that period. It should 

 be introduced, more or less, throughout the whole previous course, 

 mingled with the teaching of Geography as it is now ordinarily pur- 

 sued. But this can not be done properly and effectually unless the 

 study of the natural sciences be made a part of education from the 

 outset, as is contemplated in my series of books, beginning with the 

 "Child's Book of Common Things," and ending with the present 

 work. That this view of the matter is correct is readily seen if you 

 observe how tributary are the natural sciences to the interest and 

 value of the study of Geography, for without their contributions to 

 it this branch is nothing more than mere dry topography and sta- 

 tistics. 



The materials for this book I have drawn from various sources. 

 Foremost stand the works of Professor Dana, and especially that 



