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ROCKS ABOVE THE TACONIC SERIES. 
Another instance of complication occurs in the adjacent hill northeast of Bald mountain. 
Fig. 12 is a section illustrative of its structure. 
Fig. 12. 
a. Calciferous sandstone: towards c, on the west, it dips moderately to the east; but ascending the ridge, the dip 
increases, and finally at a, the summit, it is reversed, or to the west; but here it comes in immediate contact 
with the coarse taconic slate, b, dipping steeply to the east. Well characterized taconic slate crops out on the 
western slope, just above the main road, covered partially by debris. 
I have introduced this illustration for the purpose of clearing up some difficulties which 
might arise hereafter in the examination of this or the neighboring hills, where the cal¬ 
ciferous sandstone apparently plunges beneath the taconic slate, when viewed in certain 
positions only; for if only the western slope should be compared with the eastern, without 
a careful examination of the summit of the ridge, a very false view would be taken of the 
position of the rocks forming this hill,. 
IV. THE TACONIC SYSTEM IN RHODE-ISLAND. 
Position of the Smithfield limestone: it is the Stockbridge limestone. Other members of the Taconic system , 
Only a fragment of this system remains, it having been probably destroyed by denuding agents. Debris 
found in the soil, and in the rocks composing the Cumberland coal basin. 
In July of the present year (1844), I was induced to visit the State of Rhode-Island 7 
principally for the purpose of examining the Smithfield limestone, a rock which for a long 
time has been known in the market as furnishing an excellent lime. I had often made 
the enquiry whether this rock is an equivalent of the Primary limestone of St. Lawrence 
and Essex counties; or whether it is of the age of the Stockbridge limestone, the marble 
of the Taconic system. The satisfactory solution of this question, I deemed of sufficient 
importance for a journey to the place; inasmuch as no one, so far as I had access to 
printed publications, had expressed themselves very clearly on those points in which I 
was the most interested. 
The Smithfield limestone lies in the valley of the Blackstone river, about ten miles 
north of Providence. It occupies but a small area, and lies in the midst of the primary 
