Lnmonite ore-beds of the Limestone region. 137 
or rocks—these conditions are alike for the whole area, from its 
northern end. in Monkton, where is the most northern of the 
associated ore-beds, to the south extremity, near Pawling, N. Y., 
Which place also has its large ore-bed. The facts sustain our 
Toposition as to thé geological unity of the formations. The 
act that the belt of maximum ore-beds crosses obliquely the 
limestone area,—being near its eastern border to the north in 
€rmont, and near its western, west of the Taconic range, to 
the south,—affords additional demonstration of that unity, and 
Suggests a close stratigraphical relation between the eastern 
anc western sides and their formations. He i 
€ iron-bearing minerals include an iron-bearing limestone 
(carbonate of calcium in which iron replaces part of the cal-— 
fium) both in Vermont and. in Berkshire. e simple iron- 
Aw. Jour, 8c1.—Tamp Senies, Vow. XIV, No. 80,—Aveust, 1877. 
