GEOLOGY OF THE WHITE MOUNTAIN DISTRICT, I9I 



This stratum, so remarkably fossiliferous, is only a few yards in width where it is 

 exposed at the locality we have designated, and it there lies with a nearly vertical dip, 

 between masses of highly altered sandstone, possessing, until carefully inspected, a 

 close resemblance to granite. The white feldspathic or granitized sandstone, already 

 described as crowning the top of the hill, belongs probably to one of these including 

 masses ; but from the perpendicularity of the dip it is obviously impossible to infer 

 which was originally the superior formation. Near the summit of the ridge, however, 

 the sandstone seems to overlie the shale ; but an inversion of the dip here might very 

 naturally exist, and it is necessary therefore to appeal to some other evidence than 

 that of position merely to determine the stratigraphical order of these rocks. As the 

 altered white sandstone in the portions examined, is apparently destitute of organic 

 remains, we have no feature to guide us but its composition and aspect. These are 

 well marked and strongly indicate its identity with the Levant white sandstone, (or 

 Shawangunk grit.) To no other formation in the whole Appalachian series, except 

 perhaps the primal sandstotie, (Potsdam sandstone,) does it bear any near resemblance, 

 and its affinity even to the primal sandstone is rather remote. The shales belonging 

 to the primal rocks contain moreover scarcely any fossils and certainly none of the 

 species here enumerated, and since there is no visible hiatus in the strata indicated by 

 an unconforming dip, this argument may be held to be conclusive. We are therefore 

 disposed to regard the two formations, the white sandstone and the fossiliferous shale, 

 as the equivalents respectively of the Levant white sandstone and one of the higher 

 Levant shales near the horizon of the fossiliferous iron ore. Upon this view some of 

 the intermediate shales are absent, and when we advert to the distance between the 

 White Mountains and the nearest outcrop of the Levant series in New York, this ought 

 not to surprise us. Upon the less probable conjecture that the fossiliferous bed is a 

 portion of the Matinal shales, no assumption of a deficiency in the series is required, 

 for the Levant white sandstone comes naturally next in the ascending order. The 

 general conclusions to which we are brought by this unexpected discovery of a fossil- 

 iferous formation, related evidently to one of the earlier Appalachian periods, are not 

 however in the slightest degree affected by this trivial amount of uncertainty respecting 

 the age of either bed. We proceed therefore to state the inferences deducible from 

 the foregoing facts. 



One of the most interesting conclusions to be drawn from the evidence afforded by 

 the above described fossiliferous strata, relates to the geological age of the chain of 

 the White Mountains. These strata present convincing proofs that the region, now 

 occupied by this mountain chain, was overspread by the waters of the ancient Appala- 

 chian ocean at an era as late in the Palaeozoic ages, as the Matinal, or more probably 

 the Levant periods. Placed as the district is, immediately between the nearly contem- 

 poraneous formations of the states of Maine and New Brunswick on the one hand, and 

 Vermont and New York on the other, it fills up an interval in the area of the Appala- 

 chian rocks, which hitherto seemed vacant, and suggests strongly that the waters of 

 the Matinal or Levant eras, extended continuously across at least all northern New 



