louis; and beyond this weight no rule of value could
be established. In De Boot's day (1600) emeralds were so plenty as
to be worth only a quarter as much as the diamond. The markets were
glutted with the frequent importations from Peru, and thirteen years
before the above-mentioned period one vessel brought from South
America two hundred and three pounds of fine emeralds, worth at
the present valuation more than seven millions of dollars. At the
beginning of this century, according to Caire, they were worth no more
than twenty-four francs (or about five dollars) the carat, and for a
long time antecedent to 1850 they were valued at only fifteen dollars
the carat. Since this period they have become very rare, and their
valuation has advanced enormously. In fact, the value of the emerald
now exceeds that of the diamond, and is rapidly approaching the ratio
fixed by Benevenuto Cellini in the middle of the sixteenth century,
which rated the emerald at four times, and the ruby at eight times,
the value of the diamond. Perfect stones (the emerald is exceedingly
liable to flaw, the beryl is more free, and the green sapphire is
rarely impaired by fissures or cracks) of one carat in weight are
worth at the present day two hundred dollars in gold. Perfect gems
of two carats weight will command five hundred dollars in gold, while
larger stones are sold at extravagant prices.

Most of our aqua-marinas come from Brazil and Siberia, and small
stones are sold at trifling prices. Some of them, however, when
perfect and of fine color, command fabulous sums. The superb little
beryl found at Mouzzinskaia is valued by the Russians at the enormous
sum of one hundred and twenty thousand dollars, although the crystal
weighs but little more than one ounce. Another rough prism preserved
in the Museum at Paris, and weighing less than one hundred grains, has
received the tempting offer of fifteen thousand francs.

A.C. HAMLIN, M.D.

[Footnote A: A curious result happened to the elder Silliman when
experimenting with a Peruvian emerald before the compound blowpipe.
The reducing flame instantly melted it into a transparent green
globule. Perhaps the intense heat of this all-powerful flame, which
reduces even the diamond, recalled the colors which disappear at a
lower temperature. But this could not be done if the color was due
to organic matter, which is annihilated or modified beyond recall by
combustion.]

[Footnote B: Several of the natura