632 Forestry Quarterly. 



approximation formulae to be used in figuring values should be 

 the aim of forest finance. 



The mathematically correct formula for soil rent values is mainly 

 influenced by the chosen interest rate p, which is most uncertain in 

 its determination and which is usually based on some supposition of 

 soil value, which makes the formula to be a chain in a vicious circle. 

 Glaser proposes to obviate the difficulty by asstiming that the 

 interest on the incomes before the year r compensate the interest 

 on the expenditiu-es up to the year r, and hence the approximation 

 can be made Sr= Yr-\-'^Tr — c—ra. This looks like the forest 

 rent, but as soil rent it expresses the rettirn every r years from the 

 area unit, while as forest rent it is the annual income from r units. 



The assumption of the equality of interest charges is left without 

 basis, but the author considers it as well justified as the other 

 assumptions of the formula, namely, of eternally equal yields, 

 continuously equal rotations and interest rate. 



Setting this approximate soil value as 5;., the true soil value 

 formula would be Sr = sr.f{r), when/(r) signifies the average values 



c 

 of — , figures for f = 40 to 120 and the different species and site 



Sr 



classes. 



The author then compares the results of this and other approx- 

 imation formulae with the theoretically "actual soil value" figured 

 \\dth 3% for various species, site classes and rotations, and finds 

 his method furnishing best results. 



Having ascertained the soil values of site I and setting them as 1, 

 the following fractions were found to approximate satisfactorily 

 values for other sites. 



Site I II III IV V 



Soil value 1 .7-. 75 .42-. 47 .21-. 23 .084-. 088 



Ndherungsformeln fiir die Waldbodenwertsberechnung. Zeitschrift fiir 

 Forst- u. Jagdwesen, April, 1914, pp. 222-229. 



Dr. Wimmenauer looks back upon twenty- 



More About seven years of teaching at the University 



Soil Rent of Giessen (in Hesse) and reviews the stand 



he took on the question of soil rent at the 



beginning of his teaching activity (March, 1888). At that time 



he had defined the object of soil rent as a "satisfactory interest 



rate on all forms of capital entering into forest production." 



