CLASSIFICATION OF MINERAL LANDS. 97 



multiplying the normal value by -^, where * equals thickness 

 in feet; and 

 (c) Provided that where the thickness of any bed varies irregu- 

 larly its computed thickness (CT) over any area shall be equal 

 to the average of the measurements (AM) less the sum of the 

 difEerences between each measurement and the average of the 

 measurements (SD) divided by the sum of the measure- 

 ments (S) : 



CT=AM-^ 



4. The value of any acre within 15 miles of a railroad In operation shall be 

 determined at the rate per ton prescribed above on au estimated recoverable 

 tonnage of 1,000 tons to the acre-foot : 



Provided that if the coal is in several beds having an aggregate 

 thickness of more than 10 feet if beds less than 6 feet thick are 

 considered at the reduced thickness as prescribed above, the 

 value due to each foot above 10 feet shall be reduced 1 per cent 

 for each such foot (as in computing the price per ton on a single 

 thick bed) up to a thickness of 80 feet, above which any addi- 

 tional thickness shaU be valued at 30 per cent of the normal 

 value. 



5. This price shall be decreased one-half if the land is more than 15 miles 

 from a railroad in operation, or if it is within that limit but inaccessible owing 

 to topographic conditions; but no land shall be valued at less than the legal 

 minimum price, nor shall the price of any land exceed $300 an acre except in 

 districts which contain large coal mines and where the character and extent of 

 the coal are well known. 



6. Within the above restrictions a graded allowance shall be made for increas- 

 ing depth, and allowance may be made for any special conditions enhancing or 

 diminishing the value of the land for coal mining. 



7. If only a part of a smallest legal subdivision is underlain by coal the price 

 per acre shall be fixed by dividing the total estimated coal values by the number 

 of acres in the subdivision, but this price shall not be less than the minimum 

 provided by law. 



8. When lands which were at the time of classification more than 15 miles 

 from a railroad are brought within the 15-mile limit by the beginning of opera- 

 tion of a new road, all values given in the original classification shall be doubled 

 by the register and receiver. 



9. Review of classification or valuation may be had only on application there- 

 for to the Secretary, accompanied by a clear and specific statement of conditions 

 not existing or not known to exist at the time of examination. 



BESTOKATTON. 



After the classifications and valuations are completed the lands are 

 restored to entry. Those that contain no coal resume the status that 

 they had prior to the withdrawal. The coal lands, after restoration, 

 may be acquired under the coal-land laws at the valuation prices, 

 surface entry under the agricultural-land laws and the State selection 

 78894°— Bull. 537—13 7 



