First Second Third Fourth Fifth Sixth 
OVERHANG AT BARBERS HILL, TEXAS 31 

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TABLE I (Continued) 
MEAN SQUARES OF DEVIATION 
bf 
bf 
S 

Seventh 
and 
Poorer 
Alla’s ) Cap 2.59-2.61 
All g’s Salt 2.20-2.21 
Sediments 
2.12 t0 2.37 at 12,000 feet 
ditto 
Regional Gradient 
ditto >o, <1.5E£ 
ditto 
ditto 
No Regional Gradient 
ditto 
ditto 
ditto 
Cap 2. 60-2. 63 
Salt 2.21 
Sediments 2.13 to 2.38 at 12,000 feet 
ditto 




Cap 2.70-2.74 2.66-2.70 
Salt 2.21 also aoe 
Sediments 2.15-2.39 2.15-2.30 
Cap 2.57 
Salt 221 
Sediments 2.12 to 2.36 at 12,000 feet 
XIII-XVIII are based on cruder 
calculations. 

691 
