November 1, 1912] 



SCIENCE 



587 



tension in agriculture, in spite of the re- 

 iterated statements to the contrary. The 

 point of difference lies in the explanation 

 of their action, the one view being that 

 they are merely so much plant food which 

 must replace the removal by crops, the 

 other being that in addition to any plant 

 food value which they possess, they affect 

 the soil and produce changes and influences 

 such as are at least partially illustrated by 

 the experimental results cited here. We 

 believe that these additional — note partic- 

 ularly that I say additional — actions ex- 

 plain more fully the function of fertilizers 

 in agriculture. From the former view the 

 application of fertilizers would be re- 

 stricted to poor and so-called exhausted 

 soils and poor systems of agriculture ; from 

 the latter viewpoint, fertilizers are indi- 

 cated as well for fertile as for infertile 

 soils, as an adjunct to successful farming 

 and bringing the soil to its highest ca- 

 pacity of crop production. 



The action of fertilizers on soils is a 

 much contested question, but the weight of 

 evidence is against the assumption that 

 their effect is due altogether to the increase 

 of plant food as such. If so simple an 

 explanation were the true one, nearly a 

 century of investigation of this problem 

 by scientists of all civilized nations would 

 surely have produced greater unanimity of 

 opinion than now exists in regard to fer- 

 tilizer practise. Thoughtful investigators 

 everywhere are finding that fertilizer salts 

 are influencing many factors which con- 

 tribute toward plant production besides 

 the direct nutrient factor for the plant. 

 It is this additional influence of fertilizers 

 which makes them doubly effective when 

 rightly used and inefSeient when improp- 

 erly used. To this influence of fertilizers 

 on soil and biological conditions is due 

 their capriciousness when applied on the 

 theory of lacking plant food, and any 



study which throws further light upon the 

 mooted question is of direct help toward 

 reaching that view of soil fertility and soil 

 fertilization which will eventually result in 

 a more definite, more rational and more 

 remunerative fertilizer practise than in the 

 past, and thus bring about the more ex- 

 tensive xise of fertilizers in agriculture. 



Oswald Schreinee 

 Bureau of Soils, 

 Washington, D. 0. 



THE DSIFT IN SECONDAET EDUCATION 

 In the course of a preliminary study of the 

 conditions affecting a particular high-school 

 subject, I have been led to glean from the 

 reports of the Commissioner of Education 

 data which, tabulated or represented graphic- 

 ally, may have a certain interest. 



The table has to do with the expansion of 

 secondary education, 1890-1910. It is self- 

 explanatory, but one or two points in it may 

 be noted. First, while the population of the 

 continental United States has increased 50 

 per cent, the proportion of the population in 

 the secondary schools has been multiplied by 

 aboiit three. Second, that while the propor- 

 tion of students completing the secondary 

 course and graduating has slightly but de- 

 cidedly increased, the proportion of them pre- 

 paring for college, either classical or scientific 

 courses, has been diminished by about 60 per 

 cent. Third, that the proportion of boys in 

 the secondary schools has in twenty years not 

 varied much from 44 per cent.; also, that the 

 proportion of boys in the successive years falls 

 oif somewhat, but not as largely as I had been 

 supposing ; in fact, the " elimination " of 

 girls goes on at almost as rapid a rate as that 

 of boys. Finally, that while the amelioration 

 of conditions as shown by the number of stu- 

 dents per teacher is noticeable, the burden 

 placed upon the teacher in small high schools 

 is in this respect markedly less than in those 

 in cities of 8,000 inhabitants or more, and in 

 these small schools the improvement is much 

 greater. Of course, specialization in teaching 

 tends in some degree to counteract this. 



