350 
GYPSUM. — MARBLE. 
Valley of the Ohio gypsum is nowhere found ac* 
companying the rock-strata near the surface of the 
earth, though indications of it are discovered at 
great depths below, especially at the works on the 
Muskingum River. " Gypsum," says Dr. Hildreth^ 
" is deposited in extensive beds on the borders of 
the valley, in the secondary and transition rock at 
the surface, and may be deposited beneath the 
series of sandstone and coal, deep in the earth 
throughout the whole valley. It is seen in great 
abundance along the southern shore of Lake Erie, 
near Sandusky, and in various other intermediate 
places, quite to the borders of New- York, and in 
the interior of that state^ being found at intervals 
from the shore of the lake to the mountain ranges. 
At the salt-works on the heads of the Holstein, 
it is discovered in great abundance, appearing part- 
ly to encircle the salt region with a cordon of de- 
posites." 
Marble. — There are many beautiful and valuable 
marbles obtained in different parts of the United 
States. The Latin word marmor, from which the 
term marble is derived, was applied by the ancients 
to all stone susceptible of a fine polish, but at pres- 
ent the word is confined to such varieties of carbon- 
ate of lime as are susceptible of polish. Both gran^ 
iilar and compact limestone furnish numerous vari- 
eties of marble, but those which belong to the former 
exhibit a more uniform colour, a greater translu- 
cence, and are generally susceptible of a higher 
polish^ and, therefore, are most esteemed for statu- 
ary and other purposes. 
The uniformity of colour so common in primitive 
marble, is sometimes interrupted by spots, or veins, 
or clouds of different colours, arising from the in- 
termixture of hornblende, serpentine, talc, chro- 
mate of iron, &c. 
Vermont and the western part of Massachusetts 
abound in white and gray marbles of gre^t excel- 
