92 GEOLOGICAL REPORT—THIRTY-FIFTH PARALLEL. 
in 1851. This, according to Mr. Andrews, was 40,592 tons, and valued at $28,145. And in 
the year 1850, the quantity quarried reached the enormous amount of 79,795 tons. According 
to Dawson, the quantity quarried in Hants and Colchester districts, in 1851, was 78,903 tons, 
having a value of £10,000 at the ports of shipment; the greater part of which is exported to 
the United States for agricultural purposes. 
It is thus seen that there is an immense and inexhaustible supply of this valuable mineral in 
convenient proximity to all parts of the Atlantic coast of the United States. It is readily 
quarried at little cost, and can be loaded directly into vessels without land transportation. This 
is sufficient to show that the deposites along the route cannot become valuable as a source of 
gypsum for export. The expense of quarrying in horizontal beds is greater than in vertical 
ones, where they are exposed in bluffs; and the distance of the deposites from seaports will 
confine the use of the gypsum to its immediate vicinity. 
It is an interesting fact that selenite was well known to the ancients, who, according to 
Pliny, made bee-hives out of it, in order to see the bees at work within. According to Dr. 
Hitchcock, it was used by the wealthy in palaces for windows, under the name of Phengites, 
and ‘‘has the curious property of enabling a person within the house to see all that passes 
abroad, while those abroad cannot see what passes within. Hence Nero employed it in his 
palace.”” 
From information which I have received from Mr. Campbell, it appears that the transparent 
plates—the selenite—is found in abundance between the Sierra Madre and the Rio Grande, and 
it is extensively collected and used for window-lights. It is in use at Covero, and is carried to 
Zuñi for the same purpose. From this fact, and the description given by Gregg, I judge that 
the selenite occurs in large and beautifully clear masses. According to Gregg, it is known by 
the natives under the name of Yeso; and he states that it is found in foliated blocks composed 
of laminæ, which are easily separated with a knife into sheets from the thickness of paper to 
that of window-glass, and almost as transparent as the latter. It is used to a great extent in 
the ranchos and villages for window-lights ; for which, indeed, it is a tolerable substitute.” 1 
According to Wislizenus, extensive layers of this selenite exist in the mountains near Algo- 
dones, on the Rio del Norte, and in the neighborhood of the Salinas. "The mineral appears also 
to be used as a substitute for lime in whitewashing. It is first calcined, and then mixed with 
water, and applied to the walls of dwellings and churches.? 
GOLD. 
The principal locality at which gold in any quantity is known to occur on or near the route 
surveyed is near Santa Fé, in and around the Gold mountains. In that region there are two 
localities where the gold is most abundant. "These are known as Old Placer and New Placer. 
The former has been known and worked since 1828. It is about twenty-seven miles south of 
Santa Fé, and appears to be on the northern and western slopes of the Gold mountains, and to 
extend for several miles southward.? Dr. Wislizenus, who visited the placers in 1846, makes 
the following observations on them, and the extent of the gold-bearing region : 
** Gold seems to be found to a large extent in all the mountains near Santa Fé; south of it, 
in a distance of about one hundred miles, as far as Gran Quivrira; and north, for about one 
hundred and twenty miles, up to the river Sangre de Cristo. Throughout this whole region 
gold-dust has been abundantly found by the poorer classes of Mexicans, who occupy themselves 
* Commerce of the Prairies, Vol. i, p. 177. 
? J. W. Abert, U. £. Topographical Engineers. Report of an Examination of New Mexico, p. 509. 
* The following account of the discovery of the gold is given by Gregg, (Commerce of the Prairies, Vol. i, p. 167.) In 
1823 a Sonoreño who was in the habit of herding his mules in that vicinity, being one day in pursuit of some that had. 
strayed into the mountains, happened to pick up a stone which he soon identified as being of the same class that was to be 
ound in the gold regions of Sonora. Upon a little further examination he detected sundry particles of gold, which did 
not fail to occasion some degree of excitement in the country. The mine appears to have been incorporated as El Real de 
Dolores, but is now generally known under the name El Placer ` 
a 
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