448 



THE NATIONAL GEOGRAPHIC MAGAZINE 



ANOTHER sp^cTACuivAR BUT NOT ve;ry de;pe;ndablE guide; to the: coai, geologist : 



THE giant 30-FOOT CIvAOSAURUS 



He is too infrequent to be counted upon ; whereas the little Conch, Pyrgulifera, is omnipresent 



just below the coal formation 



of this can be brought to the surface, 

 thus making the very liberal allowance 

 of almost half for loss in mining. Four 

 hundred dollars an acre for such land 

 would thus be a charge of only i cent a 

 ton, certainly not much of a burden on 

 the coal operator or the ultimate con- 

 sumer. 



Under Uncle Sam's new classification 

 and valuation scheme, the public coal 

 lands are now handled in a thoroughly 

 business-like manner, and in sharp con- 

 trast with the old happy-go-lucky methods 

 under which coal land was sold at a fixed 

 and very low price, without regard to its 

 real value, or even disposed of under 

 agricultural or other laws at a nominal 

 rate. 



The coal-land law provides that coal 

 land shall be sold at not less than $20 

 an acre if lying within 15 miles of a 

 railroad, or $10 an acre if beyond that 



limit. Until 1907 this price had been 

 regarded as the only price, but it was then 

 decided that the figures named were 

 clearly miniuinin. Since then the coal 

 lands have been classified and valued by 

 the Geological Survey at approximations 

 of their commercial worth. During 1907- 

 1908 valuations were fixed as high as $75 

 an acre. 



In April, 1909, the Department of the 

 Interior inaugurated a valuation plan 

 based on the estimated tonnage of the 

 coal deposits. 



Since coal occurs in beds or seams, it is 

 a comparative!}^ easy matter in most in- 

 stances for the geologists to estimate the 

 tonnage with a fair degree of accuracy. 

 An acre of coal one foot in depth con- 

 tains approximately 1,800 tons, and 1,000 

 tons is allowed by the Survey as recover- 

 able. The valuation regulations take into 

 account thickness of beds, depth, whether 



