1889. | NEW YORK ACADEMY OF SCIENCES, 159 
hydrophane described by me before the Academy of Sciences 
several years ago, absorbing almost an equal bulk of water, and 
then becoming transparent. Oculus Beliand Oculus Mundi were 
names applied to a substance brought from the East several 
centuries ago, which probably was this same tabasheer. These 
specimens are of peculiar interest, since we have here asubstance 
of organic origin, not to be distinguished from one of which the 
origin is purely mineral. The color is opaque white, but it be- 
comes entirely transparent on immersion in a colorless liquid. 
The specimen of fire-opal exhibited this evening, evidently a 
water-worn fragment, was found near John Davis River, in 
Crook County, Oregon. It is transparent, grayish-white in 
color, with red, green, and yellow flames. The play of colors 
equals in beauty that of any Mexican material, and it is the first 
opal found in the United States that exhibits color. Undoubt- 
edly, better material of the kind exists where this was found. 
During the last year large quantities of gadolinite were sent 
from near Bluffton, in Llano County, Texas, twenty-two miles 
from Burnett. The occurrence of this gadolinite was some- 
what similar to that of allanite in Amherst County, Virginia; it 
has more than ordinary interest from the fact that it contains 
from forty to fifty per cent of yttria. About one thousand 
pounds were found in a single pocket, associated, it is stated, 
with xenotime, fergusonite, and euxenite. One crystal was ex- 
hibited weighing eleven pounds; another was found weighing 
thirteen pounds, and a group weighing forty pounds. The pro- 
ductions of this locality exceed in quantity and size anything 
yet obtained. 
During the summer of 1888, a small diamond, weighing about 
half a carat, was found by Mr. C. O. Helm on the farm of 
Henry Burris, about three hundred yards from Cabin Fork 
Creek, Russell County, near Adair County, Kentucky. While 
walking through an old field, on the top of a hill, Mr. Helm 
observed in the gravel this small, bright stone, which on investi- 
gation proved to be a diamond, octahedral in form, with curved 
faces, lustrous, but slightly off-color. The rock in the vicinity 
is said to be composed of granite dikes, slates, and some ‘‘ float- 
