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signed to help solve the problems related to soil productiveness, 

 such as : effects of the continuous use of large amounts of min- 

 eral fertilizers upon the physical and chemical properties of the 

 soil, and upon the bacterial flora and bacterial activity ; changes 

 that occur in a series of years when soils gradually deteriorate or 

 improve ; effect of different methods of soil treatment upon the 

 loss of lime in the drainage water ; loss of potassium and other 

 substances occasioned by manuring with lime ; loss of soluble 

 salts caused by clean cultivation ; extent to which soils under 

 field conditions are renewed by accession of the lower soil to 

 the plowed surface. 



Professor Otis W. Caldwell, of the University of Chicago, has 

 an article on " The Course in Botany" in the ] 8inua.ry Sc/iool 

 Science' and Mathematics. The whole article is well worth read- 

 ing by all teachers of botany. A suggestive full-year course is 

 suggested for high schools. The principles that, according to Pro- 

 fessor Caldwell, should determine the course will be seconded by 

 all. They are : (i) " The materials selected for use in the course 

 should have appreciable significance to the students. . . . This 

 appreciable significance may be found in a knowledge of practical 

 use of materials, a general understanding of life problems, appre- 

 ciation of the aesthetic aspects of plant life, desire for knowledge, 

 or a knowledge of the basis of agriculture or other industrial pur- 

 suits. (2) The materials must be of value for general knowledge 

 by the public. There is a general culture value in knowing plant 

 life, and the time has come when knowledge of the activities of 

 plants and the part they perform in modern life is a part of the 

 body of knowledge people must have in order to be properly in- 

 telligent as to their environment. (3) The materials of the course 

 should be organized into a series of natural sequences to make 

 possible the development of the problem-solving attitude of mind, 

 and to carry this series long enough really to give some facility 

 and efficiency in thinking." 



