lOO BOARD OF AGRICULTURE. | Jan., 



IN MAKING THE TEST IS IT NECESSARY TO WAIT UNTIL THE 

 LITMUS PAPER DRIES BEFORE DRAWING CONCLUSIONS AS 

 TO THE PROBABLE NEED OF LIME? 



When the Htmus paper was first put mto use for testing soils 

 at the Rhode Island Station a statement was found on record 

 by one of the German authorities that the paper must be dried 

 before definite conclusions can be drawn as to the need of lime. 

 It would be but natural for a farmer to do the drying in the 

 sunlight, the action of w^hich is to bleach the paper to such an 

 extent as to interfere in drawing conclusions as to the proba- 

 ble efifect upon it of the soil. The drying also meant some 

 extra delay and trouble. A careful investigation of the ques- 

 tion was, therefore, undertaken in the laboratory, which 

 showed that it was not necessary to wait for the paper to dry 

 before drawing conclusions as to the probable necessity for 

 liming. An explanation of these details is unnecessary here 

 and it would be of interest only to chemists. 



THE INFLUENCE OF LIMING UPON THE PHOSPHORUS COMPOUNDS 

 OF THE SOIL AND UPON CERTAIN PHOSPHATES USED AS MANURES. 



In the course of the liming experiments in Rhode Island 

 it was found that a soil which for years had failed to produce 

 good crops without the application of phosphatic manures, was 

 rendered capable after liming of yielding enough phosphoric 

 acid for several successive crops. Similar results have also 

 been noticed in France where superphosphates had first been 

 used without effect. 



Roasted Redondite is a phosphatic manure upon which the 

 liming of the soil has a marked influence. It contains little or 

 no soluble phosphoric acid but frequently shows upon analysis 

 as high as 35 per cent, or more of reverted phosphoric acid. 

 If introduced into ready mixed commercial fertilizers in any 

 considerable amounts the proportion of the " available " phos- 

 phoric acid actually present as " soluble phosphoric acid " will 

 be much reduced. Hence in goods where the available phos- 

 phoric acid is high and the soluble phosphoric acid is 

 very low it is obvious at once that a considerable amount 

 of bone, tankage, or roasted Redondite has probably 

 been introduced. The tendency to use the Redondite in mix- 



