irst printed in 1816), written by order of
King Sigismund I., is an exposition of the principles on which it was
proposed to reform the currency of the Prussian provinces of Poland. It
advocates unity of the monetary system throughout the entire state, with
strict integrity in the quality of the coin, and the charge of a
seigniorage sufficient to cover the expenses of mintage.

AUTHORITIES.--Rheticus was the only contemporary biographer of
Copernicus, and his narrative perished irretrievably. Gassendi's
jejune Life (Paris, 1654) is thus the earliest extant of any note. It
was supplemented, during the 19th century, by the various publications
of J. Sniadecki (Warsaw, 1803-1818); of J. H. W. Westphal, J. Czynski,
M. Curtze, H. A. Wolynski, F. Hipler, and others, but their efforts
were overshadowed by Dr Leopold Prowe's exhaustive _Nicolaus
Coppernicus_ (Berlin, 1883-1884), embodying the outcome of researches
indefatigably prosecuted for over thirty years. The first volume (in
two parts) is a detailed biography of the great astronomer; the second
includes some of his minor writings and correspondence, family
records, and historical documents of local interest. The effects of
his Italian sojourn upon the nascent ideas of Copernicus may be
profitably studied in Domenico Berti's _Copernico e le vicende del
sistema Copernicano in Italia_ (Roma, 1876), and in G. V.
Schiaparelli's _I Precursori del Copernico nell' antichita_ (Milano,
1873). A centenary edition of _De revolutionibus orbium coelestium_
was issued at Thorn in 1873, and a German translation by C. L. Menzzer
in 1879. (A. M. C.)

COPIAPO, a city of northern Chile, capital of the province of Atacama,
about 35 m. from the coast on the Copiapo river, in lat. 27 deg. 36' S.,
long. 70 deg. 23' W. Pop. (1895) 9301. The Caldera & Copiapo railway
(built 1848-1851 and one of the first in South America) extends beyond
Copiapo to the Chanarcillo mines (50 m.) and other mining districts.
Copiapo stands 1300 ft. above sea-level and has a mean temperature of
about 67 deg. in summer and 51 deg. in winter. Its port, Caldera, 50 m.
distant by rail, is situated on a well-sheltered bay with good shipping
facilities about 6 m. N. of the mouth of the Copiapo river. Copiapo is
perhaps the best built and most attractive of the desert region cities.
The river brings down from the mountains enough water to supply the town
and irrigate a conside