286 UNITED STATES OF AMERICA. 



principal mines are those on James River, in Virginia; on the Schuyl- 

 kill, near Orwicksburg, in Berks county ; near the Lehigh river, 

 in Northampton county, Pennsylvania; and near Newport, in Rhode- 

 Island. 



Gypsum, or Plaster of Paris, of an excellent quality, has lately been 

 found on the Cayuga and Seneca lakes, in the state of New -York. 



In Montgomery county, Pennsylvania, Marble of various colours 3 

 has been quarried for a number of years — It is also found at Stock- 

 bridge, in Massachusetts, at Harper's ferry, in Virginia— and in 

 Connecticut and New-York. 



Slate is quarried on the banks of the Delaware, in Wayne county? 

 Pennsylvania, about 75 miles from Philadelphia, and is extensively 

 used for the roofing of houses in that city and its vicinity — and for 

 writing slates. It is also found in Dutchess county, New-York. 



Soap Stone occurs on the Schuylkill, about ten miles above Phi- 

 ladelphia, and in the states of New-Hampshire and South-Caro- 

 lina — And Serpentine of a very beautiful green colour and compact 

 structure, is found at Newbury, in Massachusetts, and near New- 

 Haven, in Connecticut. It is of the variety called Noble serpentine. 

 Fine specimens of asbestus, or cotton stone, of a silky lustre, are fre- 

 quently found with it. 



Among the precious stones which have been found in the United 

 States, may be enumerated, zircons, beryls, cryso-beryls, amethysts, 

 rock crystals, tourmalines of various colours, as yellow, green, blue, 

 and black ; garnets, some of which are very large, agates, camelians y 

 and jasfiers, together with many other curious and interesting mine- 

 ral productions ; as actynolite, tremolite, crystallized feldspar, and 

 mica or isinglass, sulphat of barytes, phosphat of lime, fluat of lime, 

 strontites, zeolite, talc, kyanite, umber, excellent clay, ochres of vari- 

 ous descriptions, &c. &c. 



Mineral waters. ...These are numerous in the different states. 

 The springs most frequented, are those of Ballstown and Saratoga, 

 in New-York, the hot springs at Bath, Virginia, and sweet springs in 

 Botetourt county, in the same state. These will be more particular- 

 ly noticed in their respective states. 



Climate and seasons. ...No country of the same extent, exhibits 

 a greater variety in the temperature of its climate, than the United 

 States. In winter, it is much colder, than the correspondent lati- 

 tudes of Europe. But its most striking and characteristic feature, is 

 its frequent and sudden transitions from heat to cold, and vice versa. 



In 24 hours, February, 1778, the mercury fell 41^ degrees. It 

 frequently in summer, stands at 86, and even 90 degrees during the 

 day, and in the course of the ensuing night falls to 65, or even 60. 

 These sudden transitions occur particularly after storms of rain and 

 thunder : after one of these, in the summer of 1775, the mercury fell 

 20 degrees, in 1|. hours. These changes are confined to no particu- 

 lar seasons of the year. They are more frequent in the Atlantic 

 states, than those west of the Alleghany mountains. In South-Caro- 

 lina and Georgia, the mercury xises to 106 degrees in the shade — in 

 the middle states to 95 or 96, and in the eastern to 91 or 92 degrees, 

 and sometimes falls 20 and 21 degrees below 0. 



In impressing this changeable and multiform character upon the 

 climate, some of the following circumstances may have no inconsi- 

 derable influence. 



