PREFACE 



The Syndics of the Cambridge University Press 

 propose to issue a Nature Study Series of which this 

 is the first volume. 



We count ourselves fortunate in securing Dr E. J. 

 Russell as author and Soil as subject. The subject is 

 fundamental, for, just as the soil lies beneath the plant 

 and animal life wt see, so is a knowledge of the soil 

 necessary for all . iderstanding of flora and fauna. 

 The real complexit>l A the apparently simple element 

 "Earth," and the v ety of methods required for ex- 

 ploring it, are typii A of the problems which the tout 

 ensemble of the outdoor world presents to the naturalist. 



Dr E. J. Russell has not only acquired a first-rate 

 and first-hand knowledge of his subject at Wye and at 

 Rothamsted ; his own researches have recently extended 

 our knowledge of the micro-organisms in the soil and 

 their influence on fertility. Further, what is very much 

 to our purpose, he has himself had practical experience 

 in teaching at an elementary school in Wye and at 

 a secondary school in Harpenden. 



Just at the present moment, County Councils are 

 trying to push rural education and to awaken the 

 intelligence of country children by interesting them 

 in their surroundings. It is, therefore, a favourable 

 opportunity to ofl'er these pages as a concrete sug- 

 gestion in model lessons and object lessons, showing 

 exactly what can be done under existing conditions. 



