1869.] TATE AND HOLDEN—IRON-ORES WITH BASALTS. 157 
the bole have been ejected in rapid succession, the decomposition of 
the intervening volcanic flow being subsequent to the eruption of the 
superimposed rock; or, in cases where the bole has been indu- 
rated, if such do occur, the decomposition of the original rock 
was effected before the subsequent volcanic outburst; but as these 
effects were limited to simple induration, except in the case of the 
production of the pisolitic iron-ore, hereafter to be mentioned, it is 
extremely probable that these eruptions were subaqueous. 
3. Absence of Boles above the horizon of the Iron-ore—Though 
boles and lithomarges unaccompanied by an iron-ore occur below 
the iron-ore series, yet no such beds have been met with above the 
pisolitic ore, though many hundred feet of basalt have been ex- 
amined. 
Fig. 2.—Section of Galboly Mountain. 
2, 
. Pisolitic iron-ore. HC. Hard chalk. 
On the face of the Galboly mountain three hundred feet of basalt 
intervene between the pisolitic ore and the White Limestone; and 
four masses of lithomarge and bole are seen within that thickness, 
underlying different basaltic terraces (see fig. 2). A similar inter- 
stratification is also seen at Slievananee, below the section given at 
. 153. 
: The section of Cape Pleaskin presents five thin strata of ochre 
below the iron-band, and unassociated with iron-ore, in the lower 
180 feet; while that portion of the basaltic escarpment (of the thick- 
ness of 172 feet) above the iron stratum does not exhibit a single 
ochre-bed. 
A section at Carnowry, Rock Head, given by Portlock*, shows 
three thin beds of ochre or bole in a thickness of basalt above the 
* Loc. cit. p. 142. 
