572 
PROCEEDINGS OF THE SOCIETY. 
that mighty stream, he was fortunate enough to come across a very 
remarkable formation of crystallized gypsum, situated in the southern 
part of Utah Territory. He felt justified in pronouncing the formation 
remarkable, from the wonderful purity of the material, and from the 
perfection of crystalline form, but particularly from the enormous size 
of the crystals. The prevailing formation in the neighbourhood is 
sandstone and argillite, very soft, and consequently easily subject to the 
violent weathering agencies of the locality. Denudation B has been 
carried on there on a stupendous scale, and it is probably due to such 
forces that the discovery of this strange deposit of gypsum was rendered 
possible. The gypsum formation stands in bold relief on the side of 
a sandhill, as was to be seen from the photographs presented. The 
crystals occur in a cavern which is enclosed by a thick shell of the same 
material as the crystals. The external appearance of the formation is 
that of a mound, rudely egg-shaped, having a length of 35 ft., an average 
width of 10 ft., and a height, in the middle, of 20 ft. The outside, 
though rough and weather-worn, presents many brilliant crystal faces, 
and the whole glistens in the sunlight with indescribable beauty. The 
mammoth crystals project laterally inward from either wall of the cavern, 
and prisms of wonderful regularity and size rise through the compacted 
sand which forms the floor of the chamber. The stereoscopic view of 
the interior, taken by natural light and prolonged exposure, conveyed a 
better idea of the structure than words could do. 
Finding many dire results of the insuppressible spirit of vandalism 
exhibited by the Indians and cattle men who occasionally visited the 
remote spot, it was resolved by the Directors of the Desert Museum, a 
scientific establishment in Salt Lake City, to remove the best crystals 
to a place of safety. About 25 tons of excellent specimens have been 
taken out. Many single prisms, seemingly of perfect form, have been 
removed. One of the finest is 48 in. long, and of its faces one is 6 in. 
across. Another regular prism is 52 in. long, and has 19 smaller crystals 
attached to one of its faces. Crystal groups of great weight are common 
— indeed, the entire mass is to be regarded as one group. The largest 
group removed whole is over 600 pounds weight [a photograph of 
which was exhibited]. 
Inclusions of sand, clay, and liquid bubbles add beauty and interest 
to many of the crystals, and phantom crystals within the larger masses 
are prettily shown. The cleavage slab shown, 24 by 13 in., demonstrated 
the great purity and consequent perfect transparency of many of the 
crystals, and the prevailing perfection of angle is shown in the crystal 
presented. The occurrence of the crystals would suggest a true geodic 
formation. Most geodes, however, are small, such are usually measured 
in inches, and their weight is expressed in ounces or pounds. Here, 
however, was a formation of the kind, with dimensions reckonable by 
the tens of feet, and weight by hundreds of tons. 
He trusted the specimens and photographs, as also the smaller slabs 
for the use of individual Fellows, would prove acceptable to the Society, 
serving as they did to demonstrate the operations of the crystallizing 
forces on a colossal scale. 
The Chairman said that the Society was greatly indebted to Dr. 
Talmage for his extremely interesting communication, as well as for the 
