CONTINENTAL NOTES — GERMANY. 1 85 



which took place in 1787. An elaborated method, known as 

 Hennert's system, was introduced, but proved to be of no 

 practical value, and deserves no further description. As a 

 matter of fact, it provided in itself no security for continuity, 

 and when the period check was applied, the output became 

 obviously too small. The revision resulted in a compromise, 

 under which the previous output was reduced by 50 per cent. ; 

 Hennert's method thus became a system based on volume, 

 pure and simple. 



Remarkable progress was made during the next decennium : 

 the maps produced in 1795-96 contained for the first time not 

 only the local distribution of species, but of age-classes as well. 

 Nobody but a practical forester can realise the difficulties and 

 tedious labour involved in the production of this the first analytical 

 map of a forest, till then worked by an irregular selection. 



It was a splendid achievement, and marked the change from 

 a general to an individual forest treatment. The special 

 summary of the composition of the existing forest was 

 elaborated with the same care, the estimated cubic contents of 

 the various species being separated, even as regards quality. 

 The rotation was reduced to 120 years, and the annual output 

 was fixed at a still lower figure. Volume continued to be the 

 basis of the working-plan. 



The next periodical revision took place in 18 18. Both maps 

 and proposals are, at present, considered to have been of a 

 somewhat retrogressive character. Though doubtless the 

 differentiation of soils, species, age-classes, etc., can be too 

 detailed, and become an obstacle rather than a help to a 

 sufficiently broad treatment, the revision of 18 18 went too 

 far, and demanded, in order to secure equality within whole 

 compartments, sacrifices in the felling age which were not 

 justifiable. The proposals were at once considerably modified, 

 but the principle of securing such equality at some sacrifice 

 has been maintained till quite recent times. It may be harmless 

 in forests situated like those in Eberswalde, but on more 

 exposed areas other methods must surely prevail. A consider- 

 able accumulation of mature and maturing wood was found to 

 exist, thanks to the extremely conservative working since 1786; 

 but, on the other hand, an insect attack of some magnitude had 

 lowered the productive value of the older Scots pine forests. 

 Ever since 1798, all regeneration had been assisted by artificial 



VOL. XXL PART IL N 



