340 Forestry Quarterly. 



MENSURATION AND FINANCE. 



A series of comparative measurements 

 Hypsometers. with different hypsometers by Flury on 



542 trees which were afterwards felled, 

 namely, with Weise's, Christen's, Hiini's, Klein's which latter are 

 very expensive precision instruments, show that there is very little 

 difference in accuracy. The differences from the true height in 

 single tres vary between -|- 11 to 13 per cent; if height classes 

 are formed this difference is reduced to -}- 2 to 5 per cent. Other 

 investigations concern themselves with the various sources of error,, 

 like oblique position, wind, etc. 



Mitteilungen der Schweizerischen Zentralanstalt fiar das forst- 

 liche Versuchswesen. VII Band, 3 Heft., 1906. Pp. 233-286. 



The rarity of growth measurements of de- 



Growth ciduous species may lend value to the 



of tabulation of a few yield measurements of 



Ash. Ash (Europaean), published from time to 



time in various journals and compiled with 



an additional measurement by Lorey. The Europaean Ash, like 



ours, is a rapidly growing, light-needing tree. 



The height curve of the sample trees in the last area ran as 

 follows : 



Height ....1 3 5 7 9 H 13 15 17 19 21 m. 

 Age 6 15 20 23 25 28 31 35 39 43 52 years 



A careful calculation of the bark per cent led to the conclusion 

 that the usual allowance of 10 per cent is too low for older Ash 

 in open stand. Other detail measurements add interest to the 

 contribution. 



Aufnahme Ergebnisse einer Eschenprobeflache. Allgemeine 

 Forst- und Jagdzeitung. Oct., 1906. Pp. 357-360. 



