1888. ] NEW YORK ACADEMY OF SCIENCES. 17 
about two inches thick, the latter being perhaps an alteration 
.from the chalcedony. This hydrophane is very hygroscopic, 
and when a small fragment is put into water, bubbles rise from 
it for fully five minutes. In several instances, associated with 
these, were small pieces of transparent fire opal, slightly yellow- 
tinted, in regularly shaped masses, measuring nearly one inch 
by one-third of an inch. This opal, however, shows no prisma- 
tic colors. 
Blue and white barite, in crystals measuring nearly one inch 
on the prism faces, and coated with stilbite, were also found; 
likewise a beautiful crystal of sphalerite, measuring one inch in 
diameter, and what are perhaps the finest specimens of diabantite 
yet obtained, in fibrous seams, bluish-black in color, and, when 
broken, strikingly resembling the unaltered crocidolite from 
Orange River, South Africa. 
The paper of the evening was then read by Dr. H. Car- 
RINGTON BOLTON, on 
THE LIKENESSES OF JOSEPH PRIESTLEY, IN OIL, IN INK, IN 
MARBLE, AND IN METAL. 
The paper was illustrated with a collection of portraits, 
books, medals, apparatus, and other memorials of Priestley, ex- 
hibited jointly by the author and Mr. Conyers Burton, of 
Philadelphia. 
(Abstract. ) 
The speaker prefaced his paper by a brief sketch of the active 
life of Joseph Priestley, referring to his discoveries in chemistry, 
his theological and literary publications, his trials at the Bir- 
mingham riots, his withdrawal to the United States, and his 
subsequent quiet life. He quoted from Corry’s ‘ Life of Priest- 
ley” (exhibited) a passage describing the personal traits and 
appearance of the chemist. 
The speaker then described the numerous likenesses of Priest- 
ley, taking up first the known oil-paintings and the engravings 
made from them; of each he gave the history, so far as known, 
and its present ownership. He next spoke of the statues in Ox- 
ford and in Cambridge, of the Wedgwood medallions, and of the 
various medals and tokens which bore Priestley’s features. He 
referred briefly to the memorials preserved in the Royal Society, 
London; the Reference Library, Birmingham; in the hands of 
