110 Germany. 
is found in application only in Austria and Baden. 
An entirely new principle in the theory of forest 
organization was introduced, when the aim of forest 
management was formulated to be the highest soil 
rent. According to this requirement the proper harvest 
time of any stand, or even of any tree, was to be de- 
termined by the so-called index per cent., that is, a cal- 
culation which determines whether a stand or a tree is 
still producing at a proper predetermined rate, or is de- 
clining. The advocates of this principle were especially 
Pressler (professor of mathematics at Tharand, 1840 to 
1843) and G. Heyer, son of Carl Heyer, who based his 
method on his father’s formula, merely introducing 
values for volumes. Judeich, director of the Tharand 
school, also developed in the sixties a method based upon 
financial theory which is to attain the highest rate per 
cent. on the capital invested in forest production. On 
the basis of survey and subdivision of working blocks 
composing a felling series, and with a rotation deter- 
mined by financial calculations with interest accounts, 
he makes a periodic area division for determining the 
felling budget in general, and in addition employs the 
index per cent., as explained, for determining in each 
allotted stand the more exact time for its harvest. 
While these men pleaded for a strict finance calcula- 
tion, such as is properly applied to any business making 
financial results the main issue, the defenders of the old 
regime, which sought the object of forest management 
mainly in highest material or value production, advanced 
as their financial program the attainment of the highest 
forest rent as opposed to the highest soil rent. They 
neglected and derided the complicated interest calcula- 
