12 



Meyer used six soils, five of wliich contained from 0.1 per cent to 

 1.03 per cent of CaO, and the sixth, wluch must have been calcareous, 

 contained 1 1 .62 per cent of hme. Oats and buckwheat both contained 

 less lime in the dry substance when grown on the soil Avith 11.62 per 

 cent hme than when grown on the soil with 1.03 per cent of hme, 

 although the growth was shghth' greater on the calcareous soU. The 

 results with oats, therefore, confirm tliose obtained b}' Lemmermann 

 with tliis crop. 



As far as can be generahzed from these results, it seems that on 

 strongly calcareous soils many, but not all, jdants contain more lime 

 and less iron, jjotash, and silica than wlien gi-owu on noncalcareous 

 soils. 



PLAN OF THE INVESTIGATION. 



In brief, the plan of the following investigation was to grow several 

 species of plants m adjacent field plats that contaiaed vaiymg 

 amounts of calcium carbonate, and then determine the ash composi- 

 tion of the plants from the different plats. Each species of plant was 

 grown m the plats six different times, and samples of each crop were 

 kept for analysis. 



Suice the object of the investigation was to determine the effect of 

 the carbonate of hme only on the growth and mineral composition 

 of the plants, it was attemped m the following experiments to make 

 this soil constituent the variable factor affecting the growth. The 

 plats were liberally and equally supplied with fertihzers to msiire the 

 plants havmg sufllcient nitrogen, phosphoric acid, and potash avail- 

 able for their maxinmm growth. When the ramfall was not sufficient 

 the same quantity of water was added to each plat. In regard to 

 sunhght, temperature, and humidity of the atmosphere, the plants 

 ui any smgle experiment were, of course, exposed to identical 

 conditions. 



It was not expected that the results obtahicd with these soils 

 would be absolute for all calcareous soils. For mstance, the amount 

 of organic matter in a sod, the water content, and the relative 

 amount of sand and clay mflucnce to a certain extent the degree 

 that carbonate of hme affects the growth, and probably the compo- 

 sition of plants. But, as the variations in organic matter, etc., do 

 not enthely obscure the effect of carbonate of hme on plants unless 

 the amount of lime present is small, it was expected that the results 

 with our sods would show in a general wa}'' the effect of carbonate of 

 hme on the growth and composition of the plants tested. 



MATERIALS AND METHODS EMPLOYED. 



For the pm-pose of this investigation four plats 10 by 20 feet in 

 area and 2 feet deep were employed, the first plat contauiing no car- 

 bonate of Hme, the second approximately 5 per cent, the thhd 18 

 per cent, and the foui-th 35 per cent. (PI. I.) 



