New York: Agricultural Experiment Station. 257 



The basal supply of chemicals ; Was ; as follows, the quantities given 

 being added to the soil of each box at the 'time the boxes were filled: 



Table I — Basal Supply of Chemicals in Plant-food Requirement Experiments. 



EXPERIMENTS WITH P 2 Os. 



1900-1. 



1901-2. 



1903-4. 



Potassium sulphate. 



Containing K 2 . . 

 Sodium nitrate 



Containing N. . . . 

 Magnesium sulphate 



Ferric chloride 



Calcium carbonate. . 



Grams. 



.660 

 .50 

 .594 

 .25 

 .000 

 .750 

 10.000 



4. 

 2. 

 7. 

 1. 

 1. 



Grams. 

 4.660 

 2.5 

 7.594 

 1.250 

 1.000 

 1.000 

 10.774 



Grams. 

 3.723 

 2.000 

 9.196 

 1.500 

 1.940 

 1.000 

 7.909 



EXPERIMENTS WITH K2O. 



1900-1. 



1901-2. 



1903-4. 



Acid phosphate .... 



(Containing P 2 0») 

 Sodium nitrate 



(Containing N) . . 

 Magnesium sulphate 



Ferric chloride 



Calcium carbonate. . 



Grams. 

 12.712 



3. 



7. 

 1. 

 1. 



.594 



.25 



.000 



.750 



10.000 



Grams. 

 7.933 

 2. 



7.594 

 1.250 

 1.000 

 1.000 

 10.774 



Grams. 

 5.957 

 1.500 

 9.196 

 1.500 

 1.940 

 1.000 

 7.909 



In 1900-1 all the nitrogen was mixed with the artificial soil at 

 the time the boxes were filled, but in 1901-2 and 1903-4 only part 

 of the sodium nitrate was added at first, the remaining portion 

 being applied in dilute solution at intervals during the growth of 

 the plants. The total quantities of nitrogen used per box were as 

 follows : 



Table II. — Nitrogen Supply in Plant-food Requirement Experiments. 



17 



