Development of Forest Valuation. 129 
The many sales of forest property which took place at 
the beginning of this period naturally stimulated the 
elaboration of methods of forest valuation. Even the 
soil rent theory finds its basis at the very beginning 
(1799) in a published letter by two otherwise unknown 
foresters (Bein and Hyber), who proposed to determine 
the value of a forest by discounting the worth of the net 
yield with a limited compound interest calculation to the 
120th year. This idea was elaborated in 1805 by Neerd- 
linger and Hossfeld into the modern conception of ex- 
pectancy values and the now familiar discount calcula- 
tions were inaugurated by them. Cotta and Hartig par- 
ticipated also in the elaboration of methods of forest val- 
uation ; Cotta writing his manual in 1804, recognizes the 
propriety of compound interest calculations, while Har- 
tig, 1812, still uses only simple interest and exhibits in 
his book as well as in his instructions for practice in the 
Prussian state forests rather mixed notions on the sub- 
ject. 
Altogether, even in the earlier part of the period, 
there arose considerable difference of opinion and warm 
discussions, in which all the prominent foresters took 
part, as to the use of interest rates and methods of cal- 
culation. But this warfare broke into a red hot flame 
when Faustmann (1849) with much mathematical 
apparatus developed his formula for the soil expectancy 
value, and when Pressler and G. Heyer transferred the 
discussion into statical fields making the question of the 
financial rotation the issue. Then the advocates of the 
soil rent and of the forest rent theories ranged them- 
selves in opposite camps. This war of opinions, although 
abated in fervor, still continues and the issue is by no 
means settled. 
