10 The Bulletin 



For this reason it is exceedingly unwise to mix lime directly with 

 stable manure." Of course, tlie reference here is to burned lime only, 

 as this is the only form of lime which does attack and injuriously affect 

 any form of organic matter. We agree entirely with the spirit of this 

 statement, hut do not understand why caustic lime will attack and in- 

 juriously affect organic material containing ammonia before applying 

 it to the soil, and will not attack this material after it has been applied 

 to the soil. It would seem that caustic lime that would liberate am- 

 monia from organic matter out of the soil would also liberate it from 

 this organic matter pi the soil; but, in spite of the advice given above, 

 the circular advocates the use of burned lime spread directly on the land 

 and worked into the soil with agricultural implements, thus forcing this 

 caustic substance into direct contact with the soil humus where the 

 liberation of ammonia can go on without hindrance. 



On the same page, after naming the various forms of lime, as caustic, 

 carbonate, and hydrated, the circular states : "As all three of these 

 forms of lime are suited for agricultural purposes, it becomes im- 

 portant in purchasing to know the relative equivalents in actual 

 lime (calcium oxide)." Here Ave have the plain statement that 

 burned lime is suitable for agricultural purposes, and a little further on, 

 on page 8, we find the circular advocating the use of burned lime or 

 carbonate of lime, depending solely on the delivered cost of equivalent 

 amounts of calcium oxide. Here we find it also emphasizing the idea 

 that, freight rates and other items of cost considered, it will be found 

 cheaper to buy lime in the caustic form than in the carbonate form. 

 But let us see how this proposition works out : 



From our general correspondence we selected letters containing quota- 

 tions on burned "agricultural lime" from Tyrrell, Wilson, Lenoir, Pen- 

 der, and Craven counties, as representing the great bulk of the territory 

 over which burned lime has been and is most generally used. 



Assuming that the limestone from which the "agricultural lime" was 

 burned to be pui'e calcium carbonate (which is almost never the case), 

 and to burn into 1,120 pounds of calcium oxide for every ton of calcium 

 carbonate used, we find that it will take about 4,500 pounds of our high- 

 grade marl to equal, in calcium oxide content, one ton of this pure burned 

 "agricultural lime." 



Now one ton of this pure "agricultural lime" will cost, as an average 

 of the five counties named, $8.27 a ton, laid down at the station; while 

 enough high-grade marl to make one ton of this burned "agricultural 

 lime" will cost, as an average of the five counties named, $5.08 laid down 

 at the station, thus making a difi'erence of $3.19 a ton in favor of buying 

 lime in the carbonate form rather than in the caustic form as advocated 

 in the circular. Or, to put the same facts differently : 



