Mineralogy and Geology. 435 
first noticed, was but little larger than a man’s arm ; but after arduous 
labor for some hours, he succeeded in making his way into a passage 
where he could stand erect, and continuing on, numerous chambers 
were discovered, of great extent and beauty. The main avenue has 
been since examined to a distance of seven miles. One of the inner- 
most rooms, (six miles from the entrance,) which has been named the 
Rotunda, is 30 or 40 feet in diameter, and is said to be 500 feet in 
height. Beyond this there was another rotunda about 12 feet in diame- 
ter, and several hundred feet high. The chambers are splendidly ar- 
rayed in stalactites and stalagmites, many of which are of gigantic di- 
mensions. Thousands of bat’s bones covered the bottom in some pla- 
ces, and many were imbedded in the stalagmite. About a mile from 
the entrance, and half a mile from the main avenue, there is a fall of 
water, of great magnitude, whose roaring in these subterraneous re- 
cesses, has been compared to Niagara ; the cave is named, from this 
fall, the Cataract Cave. The rock in which it occurs is limestone. 
6. Geological Survey of Vermont.—Arrangements have been made 
for the active prosecution of the field labor of this survey the ensuing 
season, under the charge of Prof. Adams, whose first report has already 
been announced by us. Mr. D. Olmsted, Jr., an expert mineralogist 
and good chemist, attached to the laboratory of Yale College, has been 
associated with Prof. Adams in the survey. Vermont abounds in rich 
architectural marbles of many varieties, and other sources of mineral 
wealth, but their full value cannot be estimated until they have been 
ably developed by a geological and mineralogical survey. 
A fresh scientific interest is now shed on the explorations of this state, 
since Prof. H. D. Rogers (see his paper at p. 411 of this volume) has 
demonstrated that fossils exist in the White Mountain strata, which have, 
almost by common consent, been hitherto looked on as among the old- 
est non-fossiliferous rocks in America, and fully entitled to the epithet 
of primary. We have before us the first essay toward a colored geo- 
logical map of the state of Vermont, made up from the labors of the 
past year, with the aid of what has been already determined by Prest. 
Hitchcock and others. It is interesting to observe from it, the general 
conformity of trend in the great formations of this section, to those of 
Massachusetts and Connecticut. 
7. Stigmaria.—Another instance of the occurrence of Stigmaria on 
the roots of Sigillaria, has lately been brought under the notice of the 
Geological Society of London, by Mr. Dawson. In the Pictou coal-field 
in Nova Scotia, Sigillaria and Stigmaria are abundant; and one large 
erect trunk of Sigillaria was discovered with roots extending into the 
bed of under-clay, and these roots were decided Stigmaria ; specimens 
were laid before the Society. 
