190 ANNUAL REPORl: OF THE Oft. DoC. 



most of the lime present is there in some other compound than the 

 carbonate. Since, moreover, the principal limestone lands in Penn- 

 sylvania are clayey or loamy, rather than sandy, they require a 

 higher lime percentage than do soils of lighter texture, to produce 

 a given effect. 



It is commonly believed that lime passes readily from surface to 

 subsoil and out through the drains. The composition of drainage 

 waters shows lime salts as the most abundant dissolved constituents. 

 In Nos. 1, 2, 9, 16, 17, IS and 19. we are able to compare surface and 

 subsoil as to their lime content. Must of these soils had not been 

 recently limed, yet No. 17 alone <^hows the subsoil to be the richer. 

 It would appear from this that the downward progress of the lime 

 is less rapid than many believe. 



Regarding the potash, we find that in no case is the percentage 

 so low that the soil would be ranked as "poor," and that in but three 

 cases of alluvial and sandy soils, Nos. 8, 16 and 18, are the quantities 

 so far deficient as to rank the soils as "medium," Virtually one- 

 third of the surface soils examined are rich in potash. Limestone 

 clays are especially well supplied with potash, particularly that in 

 the limestone loams and clays. The Nittany Valley sample contains far 

 less than the Lancaster county and Bedford county soils. The shales 

 also are well supplied with this material, as are the Delaware county 

 micaceous clay and the Cecil clay, of Adams county. Comparing soil 

 and subsoil, there is a curious difference in the quantities in the 

 Norfolk gravelly loams along the banks of the Susquehanna at Ma- 

 rietta. Sample No. 7, and also sample No. 15, which in like manner 

 dilTered from the other Penn sandy loams examined, were 

 taken from the lower portions of rather steeply inclined slopes, and 

 contain more silt, and possibly more clay, than do samples 8 and 12 

 to 14, respectively. This very po.ssibly accounts for the observed 

 differences in potash. Considering the relations of soil and subsoil 

 in the case of samples 9, 16, 17 and 18, the subsoil is distinctly richer, 

 while in the case of No. 2, the surface soil has the greater percentage. 



In the case of phosphoric acid, we find a very different state of 

 affairs. All but one of the Penn sandy loams and the Norfolk grav- 

 elly loams are "poor." The Cecil clay, the Mauch Chunk red shale 

 and the Venango glacial loam are but "medium." The Conestoga 

 loam of southern Lancaster county, the micaceous clay of Dela- 

 ware county, the Hagerstown gravelly loam of northern Lancaster 

 county, and the rich elluvium of the Susquehanna, near Towanda, 

 are the only samples that would be classed as "rich" in phosphoric 

 acid. Comparing surface and subsoil, we find, without exception, 

 that the former contains the greater proportions of phosphoric acid. 

 This might be ascribed to the fact that on most of the lands analyzed 

 commercial phosphates have been used, and, being immediately con- 

 verted into comparatively insoluble substances, have not been 

 leached away, but it may also be explained from the fact that by 

 the weathering of the surface soil, the more soluble materials are 

 carried away in the drainage waters, leaving b(^hind relatively in- 

 soluble phosphates in a greater proportion to the residue. The 

 opposite tendencies of cropping would not immediately destroy the 

 balance of 7)hosphate.«? thus established. The facts here observed 

 are strictly in accord with those noted in the comparison of the 

 fresh and weathered portions of rocks, and, indeed, in the case of 

 soils, everywhere. 



