- 92 - 



soil was gradual between the check plats. The calcu- 

 lation is made by taking one third of the difference be- 

 tween the consecutive check plats and adding or subtracting 

 according to the trend of the variation. The productive 

 capacity for plat 11 was calculated on the ass-umptlon that 

 the same variationjoccurring between check plats 7 and 10 

 continued through plat 11; and plat 15 was similarly calcu- 

 lated from check plats 16 and 19. This method would appear 

 less reliable than where a check plat is in each side of the 

 plat for which the correction is made. 



