January 1, 1921] 



SCIENCE 



25 



that from cotton. The data show that wood cellu- 

 lose most nearly corresponding to cotton, taking 

 munition linters as a. standard, is obtained by re- 

 cooking "easy bleaching" sulphite pulp with soda 

 and bleaching with two per cent, of bleaching 

 powder. The practise of checking wood cellulose 

 according to the specifications for cotton is a 

 questionable procedure. 



Supply and preparation of wood for the manu- 

 facture of pulp: Hugh P. Baker. 



Farchmentizing paper and the reaction of mor- 

 dants: J. E. Minor. The work of Schwalbe and 

 Becker recently published confirms theories of the 

 author as to the reactions which occur on the de- 

 composition of cellulose during beating. The hy- 

 drolysis of cellulose forms dextrines which are 

 mucilaginous, soluble in water and easily reduce 

 Fehling solution. These dextrines are readily ad- 

 sorbed by pur© cellulose thus constituting the 

 reactive, insoluble, colloidal hydrocellulose, and 

 in this position they catalyze further cellulose 

 hydrolysis. Complete hydrolysis leaves only sol- 

 uble dextrines or sugars. For a mucilaginous ac- 

 cumulation as is desired for making parchment 

 paper, the velocity of the initial reaction must be 

 catalyzed, either by the hemi-celluloses of wood 

 incrustation, or by acid treatment of pulp prior 

 to beating. Acid treatment of pulp reduces the 

 time required to beat to mucilage to one half or 

 one tenth the original amount required, and in- 

 creases the strength of the paper made from it. 

 Pulp mucilage has a greater power of splitting 

 salts and adsorbing metal ions than has cellulose 

 and, therefore, assists in holding size, dye, coating, 

 etc. Metal impregnation weakens paper strength. 



Is it feasible to form a section of cellulose chem- 

 istry? Q. J. EssKLEN, Jr. 



Solvents for phosgene: Charles Baskerville. 

 An impelling factor in causing the Germans to 

 sign the Armistice was a knowledge of the rapid 

 development of the stupendous poison gas program 

 of the United States. One of the earliest gases, a 

 real gas, used by the Germans, was phosgene. It 

 had been manufactured on a small scale in Ger- 

 many before the war. Small amounts were ex- 

 ported to the United States prior to 1914. It was 

 being produced in this country for similar uses 

 after the blockade had shut off the importation 

 of chemicals in the manufacture of which the 

 Germans had made a specialty. It was trans- 

 ported in small quantities liquefied in cylinders. 

 "When hostilities ceased we were producing the 



poison gas for war purposes at the rate of fifty 

 tons a day, with a program nearly completed for 

 a much larger production. Soon after the Arm- 

 istice was signed restrictions were imposed which 

 prevented railroad transportation of phosgene 

 liquefied in cylinders. Uses for war gases in peace 

 times have been sought. The author has found 

 several solvents for the gaseous phosgene, among 

 them gasoline, benzine and ethyl acetate, which 

 dissolve an equal weight of the poison gas at ordi- 

 nary temperatures. The solutions exert practically 

 no pressure beyond atmospheric, so may be trans- 

 ported with safety within ordinary closed contain- 

 ers. On exposure to the air the liquid and dis- 

 solved gas evaporate. The solutions offer simple 

 means for the use of a poison gas to exterminate 

 rats and moles. On warming the solutions in 

 suitable vessels the phosgene is liberated and may 

 be used in a pure form in the manufacture of cer- 

 tain coal tar products of color or medicinal value. 

 An eleotrometric method for detecting segrega- 

 tion of dissolved impurities in steel: E. G. Mahin 

 and E. E. Brewer. Previous work has shown that 

 both non-metallic and metallic inclusions cause 

 carbon segregation in steel and the hypothesis has 

 been advanced that this is due to the steel acting 

 to some extent as a solvent for the foreign ma- 

 terial. If this is correct the electrode potential 

 of the metal should be altered in the regions im- 

 mediately surrounding the inclusion. It is not 

 possible to determine this point by the usual 

 method involving immersion of the specimen in 

 an electrolyte but a method has been devised for 

 exposing microscopic areas of metal surface to an 

 electrolyte, so that the micro-electrode thus formed 

 may be connected with a standard calomel half- 

 element and the E.M.F. of the system measured 

 by the usual compensation method. This method 

 has been applied to an investigation of the ferrite 

 bands produced by heating steel in contact with 

 metallic inclusions; it has been found possible 

 thus to measure the potential of these micro-areas 

 and to establish the fact that the ferrite of these 

 segregated portions possesses a distinctly lower 

 potential than the ferrite of tie body of the steel. 

 The work is being extended to include investiga- 

 tion of the potential of ferrite adjoining other 

 metallic and non-metallic inclusions and it may be 

 applied also to the detection of segregation of the 

 constituents of non-ferrous alloys. 



Soda-lime for industrial purposes: K. E. Wilson. 

 The work to be described in this paper was an 



