PERIODICAL LITERATURE 4T1 



It is Stated that, according to von Schrenk and Spaulding, the wood- 

 destroying fungus pomes igniarius affects the wood primarily by re- 

 moving the hgnin from the cell wall. Data presented in this article 

 controvert their conclusions. The cellulose content of a sample of 

 sound aspen was found to be 58.8 per cent and the lignin content to be 

 '7.86 per cent. Samples taken from rotten portions of the same sample, 

 attacked by Fomes igniarius, yielded 42.29 per cent of cellulose and 

 13.16 per cent of lignin. 



In discussing the chemical composition of coniferous and deciduous 

 woods, the writers state : 



"The broad-leaved trees give a considerably higher yield of furfural 

 than the coniferous woods, which latter contain much more methyl- 

 furfural-yielding substance. This substance, or at least part of it. is 

 apparently very resistant, as there always remains a considerable pro- 

 portion of it in the residue. The commercial pulps likewise contain a 

 large proportion of this substance, and it is interesting to note the high 

 resistance of the methyl-furfural-yielding substance in decayed aspen. 

 . . . Apparently there are considerable dift'erences in the types of 

 lignin substances of aspen and balsam fir which are especially charac- 

 terized by their solubility in concentrated sulphuric acid. Klason's 

 method of determining lignin by treatment with 72 per cent sulphuric 

 acid is recommended for spruce, . . . and can be used with advan- 

 tage with coniferous woods in general, but seems to fail entirely with 

 broad-leaved trees." . . . 



The writers' citation of Wisliccnius' theory of the manner in which 

 lignin is contained in wood is interesting, as he advances the hypothesis 

 (Z. Chem. Ind. Kolloide. Vol. \'I. 1910. pp. i. 2) that the lignin repre- 

 sents colloids separated out from the caml)ium sap by adsorption, one 

 part of which is reversibly and another irreversibly deix)sited on the 

 cellulose. Klason (Svensk Pappers Tidning, 1916, p. 129) favors this 

 opinion, and has determined that 6 per cent of the total ligniti is rever- 

 sibly combined with the carbohydrates of the wood. 



B. L. G. 



The Estimation of Cellulose in IVood. Pulp and Paper Magazine of Canada, 

 XVf, January 31, 1918, pp. 85-93. 



Wood-block pavements have given more trou- 



ll'ood-block ble tlirough excessive expansion and consec|Ucnt 



Failures heaving in cities in the Southern States than in 



Analyzed other parts of the country. The fallacy of the 



sand "cushion" for creosoted wood-block pave- 



nuiit^ was poiiUed out as long ago as 1914 ( .hiirricun /.ninlwrnnin. 



Ian. 24. i')i4. p. 30). An extended investigation by tin- I'. S. l-'orest 



