median screws and a kind of
noria, were used by the Romans for dewatering mines has been known for
some time. Evidence of the survival of this technology beyond the fall
of Rome remains to be found, and it is generally agreed that mining
activity declined through the first millenium. The revival and extension
of mining in the central European areas of German settlement is thought
to have occurred from the 10th century, with an intensive development of
the region known to Agricola (Erzgebirge) in the 13th century.[3]

This revival appears to have paralleled in general the political and
cultural revival, but, as in any mining region, the exhaustion of easily
workable surface deposits marked a critical point, when the necessity of
deeper mining led to the construction of supported tunnels and the
introduction of machinery for removing ores and water from deep mines.
On the basis of revisions of capital structure and mining law which he
regards as inspired by the financial necessities of deep mining, Bechtel
dates this development from the mid-14th century.[4] The mid-14th
century situation is confused by the occurrence of the Black Death,
which reduced mining activity drastically, and the events of which
Bechtel speaks have been put as much as a century later.[5] In any case,
the development of deep-mining methods had clearly made considerable
progress in nonferrous mines when the _De re metallica_ was written, in
1556.

[Illustration: Figure 1.--BRUNSWICK SILVER 3-1/2 TALER, Johann
Friedrich, 1677. (_U. S. National Museum, Paul A. Straub coll.;
Smithsonian photo 43334-C._)]

MINE-PUMPING MACHINERY ILLUSTRATED BY BRUNSWICK MULTIPLE TALERS

These large silver coins weighing up to 15 ounces were first issued
in 1574 in Brunswick by Duke Julius (1568-1589) of the Wolfenbuttel
line. Their historical background is rather unusual and interesting.

In 1570 the Duke decided to increase the output of his silver mines
in the Harz and arranged for the opening of three new mines. In
order to insure the retention of a portion of this increased silver
output under his control, the Duke decided to issue an entirely new
kind of silver coin which he called "Loeser," meaning redeemer.
These were larger than taler-size pieces, and were struck in
denominations from 1-1/4 to 16 talers. The Duke ordered that each of
his subjects was to purchase one of these large coins, the size of