October 13, 1922] 



SCIENCE 



431 



to 100 ec. in a granulated flask, an aliquot of 

 which is oxidized with standard K2Cr20f solu- 

 tion; the excess KoCroOy is titrated with ferrous- 

 ammonium sulphate solution. The alkaline fil- 

 trate is divided into two equal portions. One 

 portion is acidified with dilute H2SO4, causing 

 the beta cellulose to precipitate. An aliquot of 

 the clear solution is oxidi/.ed as in the alpha cellu- 

 lose determination for the estimation of gamma 

 cellulose. The other portion of the alkaline 

 filtrate is used for determining beta plus gamma 

 cellulose. The value for beta cellulose is arrived 

 at by subtracting the result of the gamma cellu- 

 lose determination from that of the beta and 

 gamma determination. The volumetric method 

 gives, a direct means for the estimation of these 

 three constants in determining the character of 

 the cellulose. Filtration and washing difficulties 

 of the gravimetric determination are practically 

 overcome. This method is more accurate and 

 can be carried out much more rapidly than the 

 gravimetric method of Cross and Bevan. Check 

 determinations can be made without repeating 

 the Cross and Bevan determination for preparing 

 cellulose, which procedure is necessary in the 

 gravimetric method. 



The gelatinizatiou of lignocelluloses : A. W. 

 ScnoKGER. It has been found that lignocelluloses 

 when ground in dilute alkaline solutions attain a 

 high degree of dispersion. The resulting gela- 

 tinous product when allowed to dry forms, ^•nth.- 

 out pressure, a dense, horny mass having a spe- 

 cific gravity of 1.4-1.5, which is three to five 

 times greater than the apparent specific gravity 

 of the original wood. The peptonizing action of 

 aU;ali is particularly marked in the case of the 

 hardwoods in comparison with the conifers, the 

 difference being apparently due to the greater 

 hemicellulOse content of the former. The cereal 

 straws gelatinize even more readily than woods 

 by the above treatment. 



A study of the methoxyl distribution in the 

 products of the soda cooTc of jacTc pine (Pinus 

 divaricata) : S. S. Aitar. This paper is a con- 

 tinuation of the work on the distribution of 

 methoxyl in the products of wood distillation pre- 

 viously reported. As the period of cook is length- 

 ened the methoxyl in the pulp gradually falls to 

 a minimum after two hours ' cook at maximum 

 pressure. Thereafter the loss of methoxyl is not 

 very appreciable. The liquor in its turn gains 

 the methoxyl corresponding to the loss in the 

 pulp so that all the methoxyl in the wood used 

 is found in the products at the end. The volatile 

 methoxyl derivatives in the liquor reach a maxi- 



mum in half an hour after attaining maximum 

 pressure, and then their quaaitity falls. There 

 seems to be a reversal of the equilibrium as the- 

 strength of caustic falls and more woody matter 

 is dissolved in the lye. The figures for the ligniit 

 and methoxyl contents of the pulp calculated tO' 

 percentage on the lignin and methoxyl content of 

 wood run parallel. This seems to be another con- 

 firmation for the theory that all the methoxyl is 

 associated with the lignin. 



Mannose from white spruoe cellulose: E. C- 

 Sherrard. When white spruce wood is hydrolyzed 

 with dilute acid at atmospheric pressure the 

 quantity of cellulose removed corresponds to the 

 quantity of sugar produced. Since no mannan 

 can be isolated from the wood bj the usual meth- 

 ods the mannose is probably present as a maimo- 

 cellulose and not in the adsorbed state. Other- 

 wise, it is difficult to advance an explanation of 

 the removal of a quantity of cellulose correspond- 

 ing to the sugars produced. The paper directs 

 attention to the presence of mannose as a product 

 of the hydrolysis of white spruce cellulose and 

 also to the fact that this sugar is distributed 

 through the alpha, beta and gamma celluloses. 

 While the mannose is quite easily removed by 

 means of dilute acids a part of it withstands the 

 action of alkali and is even found in cellulose re- 

 precipitated from zinc chloride-hydrochloric or 

 cuprammonium solutions. Mannose has been 

 found in the solutions resulting from the hydroly- 

 sis of white spruce cellulose prepared by the Cross 

 and Bevan method, and from soda, sulfate and 

 sulfite processes. 



Experimental work on the development of a 

 theory of the protection of wood hy preservatives: 

 E. Bateman and C. Henningsen. Practical 

 methods of preserving wood against the attack of 

 low forms of life require the injection of some 

 material which either inhibits or kills the attack- 

 ing organism. A working hypothesis on the pro- 

 tection of wood by preservatives is proposed. It 

 states that wood preservative must possess suffi- 

 cient solubility in water to produce a solution of 

 lethal concentration. When injected into wood as 

 an oil solution, the active ingredients are dis- 

 tributed in the ratio of their solubilities in water 

 and oil. The paper, which includes new data on 

 the solubilities, solubility coefficient and toxicity 

 of mono-hydric phenols, offers experimental proof 

 of the theory. 



Notes on the rosin-sizing of paper. I. The 

 reactions between aluminium sulfate and sodium 

 resinate (rosin size) soluiions: Alfred Tingle. 

 The experimental results obtained may be sum- 



