The Taconic — Marcou. 3i 
The curvatures, folds and contortions to which the Taconic 
system was subjected accompanied by enormous lateral pressure 
■explain the position of the Stockbridge and Sparry limestones 
in the area of the original Taconic. Farther north their posi- 
tions are normal and at St. Albans, Highgate Springs, Phillips- 
burgh and all over eastern Canada, they lie no more on the 
quartzytes, but at their right places above the Georgia slates. 
However even in the Taconic area, parts of the Stockbridge and 
Sparry limestones are found in their right places above the 
Georgia slates, at Bald mountain, Whitehall, Shoreham, etc. 
Very likely special lithological structure — those limestones of 
the Phillipsburgh and Swanton groups assuming a thickness so 
great [3,000 feet and more] as to give them the form of a 
great mass or belt of marble as at Stockbridge, Rutland, Mid- 
■dleburg and Winooski — combined with the proximity of the 
two great and enormous pillars of crystalline rocks of the Adi- 
rondacks. Green and White mountains, which pressed on both 
sides the broken and upheaved Taconic series, created a special 
dynamical structure for the original Taconic area, which ex- 
plains the error of Emmons. 
The other mistake of Dr. Emmons is, regarding some lenticu- 
lar masses of limestone, scattered in some places, as at Bald 
mountain, Whitehall, Cantonment hill, Snake mountain, as 
belonging to the limestone divisions of the Champlain system. 
He thought they were remnants left by denudation, scattered 
in discordance of stratification on the tops of hills formed at the 
base by the Taconic slates; or as colonel Jewett told me at Al- 
bany in 1861, bags of Champlain limestone deposed inadepres- 
sion or hole in the Taconic slates. My discovery in iS6i and 
'62 of lenticular masses of limestone and sandstone inclosed, and 
of the same age as the Taconic slates, all over the Taconic sys 
tern, gives for the first time a consistent and satisfactory expla 
nation of all those isolated masses of supposed Champlain 
limestone. I was unable to communicate my discovery to Dr. 
Emmons, who had been shut up into the lines of the Confederacy 
for two years; but I did discuss the question with colonel Jewett, 
who agreed entirely with me, adding his own observations 
around Troy, where he saw some of those isolated masses of 
limestone quarried for a lime kiln, which had been entirely 
