26 



SCIENCE 



[N. S. Vol. LIU. No. 1358 



outgrowth of work done in the Chemical Warfare 

 Service to develop soda-lime for military purposes. 

 Soda-lime for industrial purposes, however, must 

 have much greater activity and capacity and, on 

 the other hand, need not be so hard and need not 

 contain an active oxidizing agent, both of which 

 requirements seriously limited the efficiency of the 

 soda-lime used for military purposes. The paper 

 describes estensive experiments designed to deter- 

 mine the best method of manufacturing soda-lime 

 in order to get maximum activity and capacity 

 against the different gases. The factors deter- 

 mining the brand of lime to use and the best per- 

 centage of caustic soda and water were found to 

 be the most important varia,bles after the basic 

 method of manufacture was decided upon. Slides 

 will be shown to indicate the effect of each of 

 these variables on the efficiency of the resulting 

 product against C0„, 80.., phosgene, chlorine, 

 superpalite and hardness. The final formula de- 

 veloped as the result of these experiments has 

 been used with great success for a variety of com- 

 mercial purposes and has been found to be many 

 times as efficient as any of the commercial grades 

 now on the market which are made by radically 

 different processes and contain much more alkali. 



Flow of viscoits liquids through pipes: Eobt. E. 

 Wilson and M. Seltzek. 



New solvents for rosin extraction: H. K. Bkn- 

 -SON and A. L. Bennett. The use of Douglas fir 

 as a source of rosin and turpentine is discussed 

 and the method of tapping the forest trees now in 

 use to a limited extent is described. Attention is 

 called to the very large quantities of resinous mill 

 waste which could be made available for rosin 

 production under proper organization. Realizing 

 that rosin extraction has been under a heavy handi- 

 cap due to the retention of the solvents by the 

 wood to an extent of as high as 25 gallons per 

 eord in some commercial plants, a search for 

 more easily recoverajble solvents was undertaken. 

 Among those that lend themselves to rosin extrac- 

 tion are 5 per cent, ammonium hydroxide and 70 

 per cent, denatured alcohol solutions. Analytical 

 data are presented on the effect of time and size 

 of wood, on the efficiency of extraction, the de- 

 composition of the ammonia extract, the separa- 

 tion of humus from rosin and the recovery of am- 

 monia from the wood by steam distillation. The 

 following conclusions are presented: (1) When 

 resinous wood of pulp size is treated with 8 times 

 its weight of 5 per cent, ammonium hydroxide for 

 10 hours 94.5 per cent, of the rosin is extracted. 



(2) The ammonia extract decomposes slowly in 

 the air at ordinary temperatures and at 90°-100° 

 C. is rapidly and completely decomposed yielding 

 ammonia vapor and finely divided rosin and humus 

 in suspension. (3) Humus does not retain more 

 than 1.7 per cent, of petroleum ether upon heat- 

 ing at 100° C. for thirty minutes. (4) Wood 

 chips saturated with ammonia solution give off the 

 ammonia completely when steam distilled. (5) 

 Denatured ethyl alcohol at a dilution of 70 per 

 cent, is as efficient a solvent for rosin as ammonia, 

 benzene, turpentine or petroleum ether. 



Comparative study of vibration absorbers: H. G. 

 Howard. A simple instrument for obtaining rec- 

 ords of horizontal and vertical vibration in build- 

 ings was constructed. Comparative measurements 

 of the vibration absorbing capacities of various 

 materials and devices, such as cork, felt, rubber 

 air-bags, rubber balls and suspensions were made. 

 Certain arrangements of rubber balls were found 

 to be very effective. 



Note on catalysis in the manufacture of 

 ether: Hugo Schlatter. Senderens' experiments 

 (Compt'es Bendus, Volume 151, page 392) on the 

 action of aluminum sulphate in the manufacture 

 of ether were repeated in glass apparatus and 

 confirmed. When the same experiments were car- 

 ried out in a small ether still constructed of lead, 

 no difference in production was observed between 

 the usual method of procedure and the process in 

 presence of aluminum sulphate. The author's con- 

 clusions are against Senderens' theory of the for- 

 mation of a double salt, inasmuch as not only lead 

 sulphate, which is normally present in the lead 

 stills used in factory practise, but broken porce- 

 lain also gives the same results as aluminum sul- 

 phate. 



Charles L. Parsons, 



Secretary 



SCIENCE 



A Weekly Journal devoted to the Advancement of 

 Science, publishing the official notices and pro- 

 ceedings of the American Associatioi! for 

 the Advancement of Science 



Published every Friday by 



THE SCIENCE PRESS 



LANCASTER, PA. GARRISON. N. Y. 



NEW YORK. N. Y. 



Entered in the po>l-»ffice at Lancutci, Pa., ai teoond cIbh matter 



