as to the use of this method is given, and every station is asked to 

 follow it minutely. In addition to this, it is asked that other methods 

 be suggested by the stations, which will be submitted to all taking 

 part, and, upon the general approval of any one method, it will be 

 used by each according to the detailed instructions as arranged by 

 the author, it being understood that no one will offer a method for 

 trial until he has worked it out to his own satisfaction. After the 

 work above indicated has been completed, individual study on the 

 soils can be taken up, and where the study gives promise of success 

 and the method has been reduced to its simplest form, it can be sent 

 to the other stations cooperating, with the expectation that it shall 

 be used according to explicit directions. 



If all proposed methods have been carefully worked over by their 

 authors, it will require but little time for the stations to apply the 

 methods and send in the results, which results will be distributed. 

 In instances where the stations are too busy on other lines to make a 

 specialty of the work, it will be sufficient for them to do only the 

 proposed work, leaving it for such as are especially interested in this 

 line to formulate and experiment on methods. 



In this it may be seen that there is much room for individual 

 effort upon collective material, while those who supply the collective 

 material will have access to all data and proposed methods, with the 

 privilege of suggesting and amending. 



It is arranged to make a study of one soil with four kinds of crops, 

 this Bureau undertaking to supply the seed and all apparatus as far 

 as possible, analyze the crops, receive the soil samples and prepare 

 and distribute the subsamples for analysis, in addition to running a 

 control-pot of each plot. 



The work in detail is as follows : 



Select a plot 60 feet square on even, homogeneous soil if possible, 

 one which has never had any fertilizer, especially P 2 O 5 nor K 2 O. It 

 is immaterial whether old or new ground is used, it being hoped that 

 all kinds will appear in the collection of results. On this plot run 

 lines from the centers of the opposite sides, as illustrated in the dia- 

 gram (fig. 1). 



This makes four plots of about 1-50 acre each. In the center, at 

 the intersection of the lines, the soil sample is to be taken. In tak- 

 ing this sample, use the measure which will be sent for laying off 

 the surface. This measure consists of a tape attached to three 

 pegs, so as to form an equilateral triangle of 3 feet on the sides. 

 After putting one peg in the ground, draw tight one side of the tape 

 and drive in the second peg; then draw tight the two remaining 

 sides of the tape and drive in the third peg. With a spade dig out 

 the enclosed area to a depth of 9 inches, having the sides of the 

 hole vertical. Place all of this soil in the sacks which will be sent, 



