Periodical Literature. 343 



-what differences there are. The whole paper is a good example of 

 the statistical method of investigating such problems. 



Vergleichende Untersuchungen iiber die Feuergefdhrlickeit des 

 Buchen- und des Eichenholses. Zeitschrift fiir Forst- und Jagd- 

 wesen. June, 1906. Pp. 386-397. 



Recent experiments by Biisgen show that 



Hardness while hardness of wood is not a function of 



and specific gravity, it roughly approximates this 



Weight. when averages are considered. Placing a 



series of specimens in order of their specific 



■gravity and averaging their hardness in groups of five gives an 



ascending series with no very great irregularities. 



Hardness was determined by driving a needle into the wood a 

 distance of one millimeter. The lack of perfect agreement may be 

 inherent in the method used. 



Holzhdrte und Spezifisches Gewicht. Zeitschrift fiir Forst- und 

 Jagdwesen. April, 1906. Pp. 251-254. 



STATISTICS AND HISTORY. 



The forestry statistics of Germany have 



German lately been more fully elaborated than 



Statistics. ever before by action of the German Forst- 



wirtschaftsrac in deputing Prof. Schwap- 

 pach to collect them. The statistics of the State forests had before 

 been quite complete, but of private forestry comparatively little 

 got into print, and it is this portion which now has been greatly 

 enlarged, at least twelve of the large owners, representing 9 per 

 cent of this class of owners, have been willing to report the re- 

 sults of their management, and also some of the municipal forests 

 have come forward, some 20 per cent of this class being repre- 

 sented. Still, only little over 44 per cent of the total forest area 

 of Germany figures in the latest statistics, tabulated by Schwap- 

 pach for 1904. 



Altogether the area, cut, and financial results of 15,600,000 

 acres of managed forest land are reported in detail, of which 10,- 

 ^00,000 are State lands. 



