1884, 63 Trans. N. Y. Ac. Sci. 
These instances illustrated the far-reaching influences of modern 
commerce in the most remote regions of the earth, and also the in- 
creasing difficulty in determining the genuine character of supposed 
aboriginal work in jade, chalcedony, etc. 
The PRESIDENT regretted that the history of the silver images ex- 
hibited by Mr. KUNZ was not known, as they were probably of con- 
siderable antiquity. 
They were imitations of two species of South American animals, 
one the Z/ama, the other the Vicuzia ; the fibre of the wool was very 
truthfully represented, and great freedom and variety were shown in 
the general work. Dr. F. N. OTIS formerly had some silver images of 
great interest brought from Peru, and now in the Blackmore Museum 
at Salisbury, England, to which he had presented them. In Colombia 
and on the Isthmus, Chiriqui, etc., the natives had made articles of 
a similar kind. Sefior URICOCHEA,a gentleman who lived many 
years at Santa Fé de Bogota, had told him that a class of profes- 
sional gravediggers and treasure-hunters existed there, who employed 
gangs of Indians in their work, and he had seen twenty-five pounds 
of gold images melted up to pay these employees. Some of the arti- 
cles from Chiriqui had been treated by a process of pickling, the alloy 
of gold and silver having been digested ina solution and afterward 
polished. 
As to the arrow-heads, there are still some tribes of Indians at the 
West who chip their arrow-points. 
In Oregon he had formerly visited tribes who were armed only with 
beautiful bows and arrows, the shafts being constructed of reeds and 
the points of obsidian. The latter were very slender, so that they 
were broken and destroyed by a single use. Gen. FREMONT had ob- 
tained some beautiful examples of these, and had two of them made 
to be worn as ear-pendants by his wife. These were made without a 
blow, being chipped by crimping the obsidian against a piece of soft 
material, either metal or wood, held in the hand. Little force, but 
much skill and experience, were required in this manufacture. 
The PRESIDENT exhibited a beautiful specimen of grouped crystals 
of argentite, from the Batopilas mine, Mexico. 
Mr. KUNZ stated, in regard to the silver images, that, two years 
ago, five thousand dollars worth of such articles, made of gold and 
silver, were melted up at a refinery in this city. 
Dr. A. A. JULIEN reported the results of his microscopic examina- 
tion of the volcanic ash of Krakatoa, from a specimen fallen upon 
the deck of a vessel off the coast during that eruption. The material 
is almost entirely angular, only a few of the larger grains showing 
such slight rounding of angles as might have been produced by mu- 
