White limestones of Sussex Co., iV. J. — Nason. 245 
of mistake, either in the understanding of his words with regard 
to Formation II or confusion as to locality, I quote from him ver- 
batim: "The blue limestone of the Kittatiny valley, exhibits, in 
certain localities, some highly impressive and remarkable phenom- 
ena of alteration of structure, induced by the heating agency of a 
series of igneous injections. 
"The altered bands of the rock may be grouped into two distinct 
belts ranging from N. E. to S. W. parallel to the general strike of 
all of the strata in this quarter of the state. The more north- 
eastern of these belts occupies, at intervals, the valley which lies 
immediately at the foot of the Hamburg or Wallkill Mt. , through- 
out nearby its whole length, keeping usualty towards its northwest- 
ern margin, or near the base of the Pochuck Mt. , and the belt of 
hills in its prolongation to the S. W. namely, the hills north of 
Franklin, Pimple hills and the hills north and west of Sparta ami 
Lockwood. The northeastern tract first shows itself at Mts. Adam 
and Eve, in New York, about five miles beyond the state line, and 
has its southwestern termination in the neighborhood of Lock- 
wood. 
"Over this whole distance, though the altered material exhibits 
considerable diversity in regard to the imbedded minerals which it 
contains, yet the main mass of the rock, or the calcareous paste 
investing them, remains to a great extent, of a uniform character 
as to structure and color." Farther on he makes mention of the 
coarsely crystalline limestones in the following manner. "When 
destitute, or nearly so, of the extraneous minerals often diffused 
through it, the prevailing condition of the rock is that of a white, 
perfectly crystalline limestone. An extreme degree of develop- 
ment of the crystalline structure had assumed the condition of 
rhombic calcareous spar. ' ' 
"It is often then semitranslucent, but more frequently it is of 
an opaque white and occasionally of a pink hue, resembling some- 
what reddish feldspar. These varieties may be regarded as the 
altered rock under its most characteristic features, and are to be 
viewed as exhibiting tin limit of alteration of which the limestone 
has been susceptible by igneous action, when it has been pure 
or consisted of little else than carbonate of lime. When of such 
aspect and structure the mineral most usually disseminated through 
it is plumbago, in small brilliant plates, often perfectly hexagonal. 
Beside this highly developed crystallization, it presents every grada- 
