Periodical Literature. 643 



property of entering such an intimate chemical compound with 

 the cell walls and any remaining protein contents, that all cells or 

 vessels are permanently, mechanically closed on the outside to 

 prevent effectively the entrance of atmospherilia and their con- 

 comitants ; 



2. That the metal parts coming in contact with the wood are not 

 attacked by acids becoming free, since then the antiseptic effect 

 is offset by mechanical wear. 



The Riiping method (see F. Q. vol. Ill, p. 321) intended to 

 cheapen the process and introduced on the Prussian and Imperial 

 railroads, consists in fully impregnating the tie with tar oils and 

 then partially evacuating them again, so that a normal beech tie 

 contains only 45 lbs. of oil instead as formerly, 80 lbs. The re- 

 moval of the surplus leaves the lumina of cells and vessels empty, 

 and hence there is nothing left to seal these openings by the sub- 

 sequent thickening of the oils ; only the walls profit by the 

 absorption of the phenyl acid. 



That the full amount of tar oil is needed may also be deduced 

 from the fact that the amount of a mixture of tar oil and zink 

 chloride which a tie will take up amounts to y6 lbs. 



The author doubts whether the impregnation of the cell walls 

 alone suffices. 



Kritische Beleuchlung des tieuen Riipingschen Schwellen-Trankungs- 

 verfahren. Schweizerische Zeitschrift fiir Forstwesen. September, Octo- 

 ber, 191 1. Pp. 255-259. 



STATISTICS AND HISTORY. 



Students of the early forest history of 

 Forest Germany will welcome the verbatim repro- 



Ordinance duction of the forest ordinance of Bishop 



of Julius for the cloister forests of Wtirzburg 



Wiirzhurg. from the year 1574, the property compris- 



ing at some time over 150,000 acres. This 

 ordinance laid down the principles under which the property and 

 other broadleaf forests were managed for centuries. 



Forstwissenschaftliches Centralblatt. August, September, 191 1. Pp. 

 476-496. 



