EXPERIMENT STATION BULLETINS. 



507 



for several days. Solutions for analysis are hardly ever used after a pro- 

 tracted (48 hour) extraction. Solutions are gathered from time to time 

 and placed in a refrigerator to retard the bacterial action. Care is 

 taken to prevent chemical changes in the solution by using resistance 

 glass. 



PLATE 2. FILLING THE CYLINDER. LITTLE OF EACH HANDFUL IS TAKEN FOR 

 A COMPOSITE SAMPLE FOR MOISTURE DETERMINATION. STYLE OF TAMPER 

 IS ALSO SHOWN. 



When cleaning out the cylinders, the oil that is superimposed on the 

 soil is saved and can be used again provided one strains it to get rid of 

 the dirt that it might contain. It is found that in order to clean out 



