198 HANDELVistula. In Thorn, he married Barbara Watzenrode, the daughter of a patrician
family, and there his fourth child, also Mikolaj or Nikolaus, was born on 19
February 1473. In this way, the early life of the astronomer was closely associ-
ated with the Vistula trade. The father's commercial wealth and the mother's
ecclesiastical relatives ensured him a cosmopolitan education, in Konigsberg, in
Cracow, and eventually in Bologna and Padua. From 1510, however, he settled
again in his native parts. His scientific research was facilitated by a tranquil life
as canon of the Warmian Chapter at Frauenberg and here his revolutionary
treatise on the motion of the earth round the sun was conceived, tested, and
written.
In the lifetime of Copernicus, the Vistula Trade developed by leaps and
bounds. In terms of exported grain measured in lasts* it rose from 5,573 in
1491-2, to 10,000 in 1537, to 66,007 in 1563, and to a peak of 118,000 in 1618.
The figure for 1618 was never repeated. But the volume of trade remained sub-
stantial. The decline was graceful through the seventeenth and eighteenth cen-
turies. Like the Vistula itself, the grain continued to flow - erratic and
unpredictable; but as time went on, the years of flood grew ever more rare, and
the years of ebb ever more frequent. During all this long period, the Grain Trade
provided an important stimulus, and was the main index, to the economy of the
Republic as a whole.^1 (See Map 13.)
The cycle of the Vistula Trade began with the arrival in Danzig of the foreign
entrepreneurs.^2 In the early period, they sailed in for the season, arriving on the
Spring tides in March or April and weighing anchor in October before the win-
ter storms. Later on, they settled in Danzig permanently. In the main, they rep-
resented Dutch firms, well established in the Baltic moederhandel (Mother
Trade). By 1650, some fifty Dutch firms maintained resident agents in Danzig,
frequently younger sons like Arndt Pilgrom, Helmut von Tweenhuysen, Dirck
van der Wolff, Marcus and Pieter Pels, Daniel de Maires, GillesThibaut, Jan
Voyrknecht, Hans Ghybrechtsen de Veer, or Jacob Jacobsen, whose family
businesses were based in Amsterdam. A number of them, like Cornells
Vlaminck or Floris Hackelaer de Jonge, obtained full citizenship in Danzig, just
as Danzigers like Wessel Schenck, Hans Schultz, or Ernest Kleinfeldt established* The Danzig last or 'load' was a measure of capacity equivalent to 3,101 litres of rye, or
roughly 2.3 tons. (Its exact weight varied according to the commodity, of course. 1 last of
frothless beer was equivalent to 2,644 litres; to 2,760 litres of frothy beer; or to 2,264 litres
of wine.) It was divided into 60 Scheffel/korczyk or 'small bushels', of 52 litres. It was
approximately 10 per cent smaller than the Polish wholesale 'laszt', which, at 3,440 litres of
rye, was designed to include an automatic commission for the seller. The Polish laszt was
often divided into 30 Varsovian bushels or korzec, each of which at 114 litres was twice as
large as the Danzig Scbeffel. In Malopolska, the Cracovian korczyk was equivalent to 34
litres. The profusion of Vistula grain measures was standardized in 1850 by the Prussian
Customs Service which fixed the Scheffel/korczyk at 50 litres of rye.