CHAMPLAIN DIVISION. 
367 
1. Hudson-river group, 
2. Utica slate. 
3. Trenton limestone, 
4. Black-river limestone, 
5. Calciferous group. 
6. Potsdam sandstone. 
These rocks form a natural series, and seem to be due to certain modifications of the same 
cause acting over a vast area in North America. They are supposed to underlie three-fourths 
of the whole territory of the United States, and to occupy the surface of one-half, the re¬ 
mainder being covered by depositions of more recent date. 
Along their eastern line of outcrop these strata have been much deranged in position since 
their deposition ; having been broken up and tilled at various angles, bent, wrinkled and con¬ 
torted in almost every conceivable manner, and elevated into hills and mountain chains. The 
whole breadth of their outcrop on the east, from Vermont to Carolina, except at the outlet of 
the valley of the Mohawk, is upturned and deranged over a breadth from five to more than 
fifty miles. The whole may be referred to one great axis of disturbance, with many subordi¬ 
nate parallel fractures, and synclinal and anti-clinal axes, ranging from Canada to Carolina, 
and nearly parallel to the general trend of the coast. 
Numerous sections and diagrams illustrate facts observed in the First geological district of 
New-York, along this axis of disturbance ;t but others equally striking, and some of arched 
and wrinkled strata on a magnificent scale, may be seen in Maryland, along the route of the 
National road, between Hagerstown and Cumberland ; and others might be mentioned in Vir¬ 
ginia and Pennsylvania, on this belt of disturbance. These and numerous others in those 
States will doubtless be described by Professors H. D. Rodgers and W. B. Rodgers, the geo¬ 
logists of those States. 
I No. 3 Pennsylvania survey. 
I No. 2 do do. 
No. 1 do do.* 
* The synonims of the above members of the Champlain division, as used in the geological reports of the States, and 
Eaton’s Geology, are subjoined. 
{ Frankfort slate group; Frankfort slate and rubblestone; Green slate and rubblestone; 
Pulaski shales; Grey wacke, G. slate, G. shale. Slaty greywacke and Transition 
argillite of the Annual Geological Reports; Greywacke and Metalliferous grey¬ 
wacke of Eaton. No. 3 of the Pennsylvania Survey. 
f- ( Mohawk slate; Black slate and shale; Fairfield slate; Graptolitic slate. Transition 
^ ^ .( argillite, Wacke slate. Glazed slate of Eaton. No. 3 of the Pennsylvania Survey. 
Trenton limestone. 5 Metalliferous limerock of Eaton; Trenton limestone of geological reports. No. 2 of 
( the Pennsylvania Survey. Cliff limestone of the Ohio Survey, 
f Mohawk limestone; Birdseye limestone; Base of the Trenton limestone; Bald moun- 
I tain limestone; Blue limestone; Chazy limestone; Black marble of Isle la Motte; 
Black-RIVER limestone. ..Neeleytown limestone; Seven-foot tier of the Geological Reports; Metalliferous 
I limerock, Transition, Sparry and Chequered limerocks of Eaton. No. 2 of the 
Pennsylvania Survey. 
o., pxppRnrra pcpittr 5 Calciferous sandrock, and Transition sandrock of Eaton ; Barnegate limestone, New- 
ous GROUP.^ Umestone; Warwick limestone. No. 2 of the Pennsylvania Survey. 
Potsdam sandstone . Potsdam sandstone; Keeseville sandstone. No. 1 of the Pennsylvania Survey. 
t Vide PI. 6, fig, 7 ; 
— 7, — I to 9 ; 
— 8.— llolO; 
— 9,— lto21; 
— 10,— ltol4; 
— 11,— ltol4; 
PI. 12, fig. 2 to 8 
— 13, — 1 to 6 
— 14, — Ito 7 
— 15; 
— 16; 
— 17; 
PI. 18 ; PI. 28, fig. 1, 2, 3 ; 
— 23, fig. 1 to 8; — 29 ! 
— 24, —Ito 6; —36, fig. 6, 7; 
— 25,'— 1, 2, 4 ; — 38, — 1 to 14; 
— 26, — 1 to 7 ; — 39, — 1 to 4; 
— 27, — 5, 7, 8, 9; -40,-3 to 10. 
