NATURAL HISTORY. 



40 



CALCAKIO-MICA SLATE. 



CLAY SLATK. 



LIMESTONE. 



quantities, up to the time of the discovery 

 of gold iu California ; amountinii' in the 

 whole to only a few hundred dollars. Since 

 the geological survej' of Canada has been 

 in progress, more attention has been given 

 to the subject, and it is found that the 

 auriferous district is quite extensive. Du- 

 ring the last three or four years tlie search 

 for gold has been prosecuted more exten- 

 sively, and the yield has amounted to 

 several thousand dollars. In Ascot, near 

 Sherbrooke, gold has been found in veins, 

 associated with copper pyrites in a quartz 

 gague; and it is reported that a lump of! 

 gold, weighing 14 oz., was obtained in that 

 vicinity iu the fall of ] 8-52. 



The steatite, or soapstone, and the ser- 

 pentine, which we have mentioned, as in- 

 dicating the line of the gold formation, are, 

 probablj', destined to be of quite as much 

 economical value to the state, as the gold 

 itself. The steatite is abundant, and is, in 

 many places, of a very good quality. It 

 has been quarried at Grafton, liridgewatev, 

 Bethel, Moretown, Waterville, and, per- 

 haps, a few other places. The serpentine 

 is largely developed at Cavendish and 

 Ludlow, at Koxbury, and at Lowell and 

 Tro3^ jMucli of this serpentine is compact 

 and firm, beautifully variegated with every 

 shade of green, from the lightest tints to 

 an almost perfect black ; and, as it admits 

 of a high polish, and is unalfected by heat 

 a.nd acids, it forms a most valuable orna- 

 mental marble. It has long been used, to 

 a limited extent, in some of the neighbor- 

 hoods where it is found, for fire-places, 

 centre-tables, &c., and the opening of rail 

 roads, through these severallocalities, will, 

 probably, be the means of bringing this 

 valuable marble extensively into use. 



Calcario-juca Slatk Divisiox. 



Under this general name, we embrace all 

 the territory of Vermont, not included in 

 the divisions already described, Vtith tlie 

 exception of a few tracts of granite. It 

 has been called the cnlairio-inica slate 

 foi'mation, or division, from the fact, that 

 it consists, to a very considerable extent, 

 of impure limestone, interstratiiled with 

 argillaceous and mica slate. These three 

 constitute the principal rocks, but they, in 

 many parts, run into several other varie- 

 ties of slate. Through the central part of 

 Orleans county, and in Caledonia county, 

 are extensive ranges of what might properly 

 be called hornblende slate. In the northern 

 part of Essex county, extending into Cana- 

 da, is a range of siliceous slate ; and in the 

 southern part of that, county there is a 

 considerable development of chlorite slate. 



The western portion of this formation, 



from Barnard northerly to lake Memphre- 

 magog, is mostly clay slate. This slate 

 constitutes a largo proportion of that beau- 

 tiful and fertile swell of land extending 

 from Winooski to White River, through 

 the towns of Berlin, Williamstown, Brook- 

 field and Randolph. It is also largely de- 

 veloped in the north part of Montpelier, 

 and in Calais, Cr.aftsbury and Coventry. 

 At Berlin, this slate has been found to 

 answer very well for roofing ; and it is not 

 improbable that good roofing slate will be 

 obtained from some of the other localities, 

 which we have mentioned. 



Clay slate also exists, in large quantities, 

 along the Passumpsic and the west bank of 

 the Connecticut river, in the counties of 

 Orange and Caledonia, and also in the 

 southeastern part of "Windham county. At 

 the latter place, it extends through the 

 towns of Guilford, Brattleborough and 

 Dummerston. The slate here is found to 

 he very suitable for roofing, and has been, 

 more or less, quarried for that purpose for 

 many years. 



The mica slate of this division is not, in 

 general, very well characterized as mica 

 slate. Indeed, the slates, or shales, of this 

 division, appear to be a combination, or 

 jumble, of almost all the known varieties, 

 sometimes exhibiting a predominance of 

 one kind and sometimes of another ; and, 

 again, we find the materials of three or four 

 dift'erent varieties comiiined in a single 

 stratum. Thei-e are, hi^wever, some small 

 tracts, to which the above remarks are not 

 applicable. This is the case with some 

 parts of Windham and Windsor counties, 

 where mica slate is found, well character- 

 ized, and forming a valuable and beautiful 

 material for flagging. 



Tlie limestone of this vUvision is, every 

 where, very impure, containing a very 

 large proportion of siliceous sand. It is 

 burned in several places for quicklime, but 

 the lime is nowhere of a good ([uality. It 

 is made to answer i)i mortar for stone work, 

 where better is not to be had ; and it is 

 usefully applied, in agriculture, as a fer- 

 tilizer, to soils deficient in lime. But the 

 lime made from the Ijeds of shell-marl, 

 which abound in this division, though that 

 is not of the best quality, is much pi'eferable 

 to the .above, both for the purposes of 

 masonry and agriculture. 



The color of this limestone, where unaf- 

 fected by the weather, is of a bluish shade, 

 and the stone is very compact and homo- 

 genious, splitting, or breaking, with nearly 

 equal facility, in all directions. Where 

 long exposed to the weather, it is recognized 

 at once by its rust-colored, rotten surfiice. 

 This rotten surface consists of the siliceous 

 sand, which remains after the lime, which 



