Alfalfa in Kansas. 227 



the entire area to be of any special concern to the farmer who is liming 

 soils. As we progress westward we find the limestones changing in 

 hardness and color, and one would expect their chemical composition 

 would change also. In this, however, one is mistaken, because, with minor 

 exceptions, the composition remains substantially the same. If we travel 

 still further west into the regions of the limestone so extensively used 

 for fence posts throughout a zone reaching entirely across the state, we 

 find here that the chemical composition is almost the same. Still further 

 west we have the chalk beds of Kansas, which are nothing but limestone, 

 and the composition of those is substantially the same as that of the 

 hardest limestones in the eastern end of the state. 



Pure limestone, could we find such, would be 100 per cent carbonate 

 of lime (CaCOs). We may take this as our standard for purity, and 

 gauge other samples by it. No limestone anywhere in the world has 

 ever been found that would analyze 100 per cent pure. Kansas lime- 

 stones rarely fall under 90 per cent pure, and with equal rarity exceed 

 95 per cent in purity. We may say, therefore, that limestones in the 

 east will analyze from 88 to 96 per cent pure; also, that the softer lime- 

 stones in the middle part of the state have substantially the same com- 

 position, and the chalk beds in the west do not differ from this in any 

 material respect. This is so high a degree of impurity that our Kansas 

 limestones are of little value for the production of ordinary lime. It is 

 one of the strange features of commerce in Kansas that lime is shipped 

 into the state from outside, although perhaps no other state in the Union 

 is better supplied with large amounts of limestone than Kansas. The 

 impurities ranging from little more than 10 per cent in extreme cases 

 down to less than 5 per cent make Kansas limestones impossible for the 

 production of a high-grade lime. 



What are these impurities? Are they anything which would injure 

 the soil should we apply such limestone to the soil as a fertilizer? Or, are 

 they of such a nature that their effect would be neutral, so that their 

 presence is objectionable only on account of their acting as a dilutent? 

 An affirmative answer should be given to the last question. The impur- 

 ities are of such a nature that they do no harm when added to the soil. 

 Their main objection in fact, their only objection therefore, is on ac- 

 count of their diluting the limestone to that extent. This makes it so 

 that one may feel perfectly safe in applying Kansas lime to the soil for 

 agricultural purposes, because one may know that he is adding nothing 

 whatever that would be in any way objectionable. Chemical analysis 

 shows that the impurities consist almost entirely of silica (SiCh), 

 aluminum (Al^Oo), and iron oxide (Fe 2 O3). We have probably a very 

 slight trace of the alkalies, and in some cases an appreciable amount of 

 magnesia, but not to any considerable degree. The soft limestone in 

 middle and western Kansas which for a quarter of a century or more 

 have been called "magnesian limestone" do not carry magnesia to any 

 considerable extent. The name is a misnomer which should be done away 

 with and forgotten. The soft limestones in general will make just as 

 high-grade lime as the harder limestones throughout the state. 



