904 



Rural School Leaflet. 



14. Keep all glassware perfectly clean. 



15. After washing the glassware, rinse it thoroughly in clean water 

 to remove soap powder. The soap powder and the acid form a violent 

 chemical reaction. 



Note. — If the teacher has no directions for making the Babcock 

 test, application should be made for the December issue, 1907, of the 

 Cornell Rural Leaflet. 



Fig. 39. — Making the Babcock test 



FORMATION OF SOIL 

 By E. O. Fippin 



We have seen that the differences which we observe in plants as they 

 grow in the field are largely the result of differences in the character of 

 the soil conditions. These differences are expressed through the feeding 

 of the plant so that anything which modifies the food supply in any way 

 has an influence on the form and development of the plant. Now the 

 food supplied to the plant may be affected in many ways. It may be 

 absolutely lacking, or it may be beyond reach, or it may not be in a 

 form for the plant to use, just as a horse may starve, not simply because 

 there is no food but because it is in the bin or because it is corn cobs 

 instead of timothy. 



The soil is the home of the plant in which it feeds, or is fed and warmed 

 and in which it grows — well if the home is comfortable, poorly if it is cold 

 and destitute. This home has been constructed by nature and all about 

 we have a chance to examine its construction and see its appointments. 

 This month, November, we would best take another field trip, not only 

 to see the things we observed last month, but to see the soil in the malf-^ 



