464 ADDRESS OF T. STERRY HUNT. 
have broken the strata, given them an eastward dip, and caused the 
newer beds to pass successively beneath the older ones, thus pro- 
ducing an apparently inverted succession, and making their present 
seeming order of superposition completely deceptive. In speaking 
of this supposed arrangement of the members of his Taconic sys- 
tem, Emmons alluded to them as “ inverted strata ;” while by Mr 
Marcou, the strata were said to be “overturned on each side of the 
crystalline and eruptive rocks which occupy the centre of the chain, 
producing thus a fan-shaped structure,” etc.* I have elsewhere 
shown that this notion, though to Some extent countenanced by 
his vague and inaccurate use of terms, was never entertained 
by Emmons, whose own view, as defined in his Taconic System (p. 
17),t is that just explained. 
The view of Emmons that there exists at the western base of 
the Green Mountains, older fossiliferous series underlying the 
Potsdam, met with general opposition from American geologists. 
In May, 1844, H. D. Rogers, in his address as President, before the 
American Association of Geologists, then met at Washington, crit- 
icised this view at length, and referred to a section from Stock- 
bridge, Massachusetts, to the Hudson River, made by W. B. Rogers 
and himself, and by them laid before the American Philosophical 
Society in January, 1841. They then maintained that the quartz- 
rock of the Hoosic range was Potsdam, the Berkshire marble iden- 
tical with the blue limestone of the Hudson valley, and the asso- 
ciated micaceous and talcose schists, altered strata of the age of the 
slates at the base of the Appalachian system ; that is to say, pri- 
mal in the nomenclature of the Pennsylvania survey. 
In 1843 Mather had asserted the Champlain age of the same 
crystalline rocks, and claimed that the whole of the division was 
there amenna including the Potsdam, the Hudson River group, 
and the intermediate limestones. The conclusion of Mather was 
_ cited with approbation by Rivets, who apparently adopted it, and 
oduan 
mptes Rendus de PAcad., LII, 804. 
ya my farther discussion of the matter, Amer. Jour, Sci., II, xxxii, Side xxxiii, 
135,281. Itis by an ti ht that I have, in the latter Piae, page 136, repres! sented 
Barrande as shar e misconception of ahi although his language, without 
er s crutiny, Bi lead us to such a conclusion. In fact in the Bull. 500. Geol. de 
France (II, xv "i, 261), in an elaborate study of ra Taconic question; Barran a se 
a section us, * and then procee eeds 
that the renversoment or overturn is only apparent, by explaining, in the an p 
Emmons, the view already set forth above. 
t Geology of the Souther District of New York, p. 438 
