428 



SCIENCE 



[Vol. LVI, No. 1450 



of the ink to each of these properties has been 

 studied experimentally, and briefly summarized 

 results are given. The tests now in use by the 

 Bureau of Standards and others are recommended, 

 with modifications, with emphasis on the more 

 practical tests. A system of rating giving equal 

 weight to the four fundamental properties is sug- 

 gested. Only iron tannate ink is considered in 

 full, but the properties of other inks are dis- 

 cussed briefly. 



Non-metallic inclusions: their infiuence upon 

 ferrite segrerjation in steel: E. G. Mahin and 

 H. "W. BoTTS. In this paper is presented addi- 

 tional evidence to support the view that non- 

 metallic inclusions in steel are centers of zones of 

 segregation of soluble impurities, and that the 

 segregation of these impurities is the primary 

 cause of ferrite segregation. Giolitti's recent 

 papers are discussed and his theory that only 

 ' ' oxidized ' ' inclusions have any effect upon 

 ferrite segregation is held to be untenable. Oxi- 

 dation rings and sulfide halos have been studied 

 and discussed in this connection, and photomicro- 

 graphs are reproduced to illustrate the points at 

 issue. H. M. Howe's conception regarding the 

 mechanism of ferrite genesis is regarded as being 

 correct for all steels except those cooling fairly 

 rapidly from the liquid state. 



The determinaiion of various mono-hydric 

 phenols hy the phenol reagent of Folin and Denis: 

 Carleton Hbnningsen. The phosphotungstic- 

 phosphomolybdic acid reagent of Folin and 

 Deuis ofCers a means for the quantitative deter- 

 mination of a number of mono-hydric phenols in 

 dilute aqueous solutions. The nature of the color 

 produced with these phenols fulfills most of the 

 requirements of a colorimetrie method. The in- 

 tensity of the color produced is dependent upon 

 the concentration of the particular phenol in pure 

 aqueous solutions free from reducing agents. 

 B-naphthol and isoamyl phenol can be used as 

 satisfactory standards for color comparison and 

 offer an advantage over the much used carbolic 

 acid in that they are solids at ordinary tempera- 

 tures and can be weighed direct with ease. 



The acid value of varnishes: Marks Nbidlb. 

 The correct determination of the acid value of 

 varnishes may be based upon two conditions: 

 (1) The varnish must be of low viscosity so tliat 

 on shaking with alcohol the distribution of the 

 acid ingredient between the alcohol and the var- 

 nish solvent may quickly reach equilibrium; (2) 

 If standard aqueous alkali is used for titrating, 

 after having added alcohol, the final concentra- 



tion of water in the alcohol layer should not be 

 greater tha,n 30 per cent, or low results will be 

 obtained due to hydrolysis. 



Propionic acid and Tcetones from whey: E. 0. 

 Whittier and J. M. Sherman. The factors 

 affecting the propionic fermentation of lactose 

 have been investigated and conditions determined 

 whereby approximately 2.4 pounds of propionic 

 acid and one pound of acetic acid may be obtained 

 from five pounds of lactose in twelve days' incu- 

 bation. A mixed culture of Bact. Acidi Pro- 

 inonici (d) and Lactoiacillus Casei incubated at 

 30° C. for three days is used for the inoculation 

 of the previously sterilized and buffered whey. 

 The mixture of propionate and acetate obtained 

 may be either converted into the free acids and 

 refined or distilled to yield a mixture of acetone, 

 methylethyl ketone and diethyl ketone. 



Pittsburgh as an industrial center (historical) : 

 J. H. James. The greatest of Pittsburgh's re- 

 sources is bituminous coal, upon which is built 

 the whole metallurgical development of the dis- 

 trict. The glass industry began developing some- 

 what before the iron, and has had an uninter- 

 rupted growth, until to-day its tonnage makes 

 this one of the greatest glass districts of the 

 world. In iron development the stages were pig 

 iron principally for foundry iron at first, puddled 

 iron, crucible steel, Bessemer steel, basic open 

 hearth steel. The fuel first used was charcoal, 

 then beehive coke, then natural gas for basic 

 open hearth steel, and to-day the trend is towards 

 by-product coke, utilization of the coke oven gas 

 in steel manufacture supplemented by producer 

 gas from bituminous coal, offsetting the decline 

 in natural gas. Secondary to the above group 

 are the iron and steel fabrication industries and 

 chemical industries. Most of the chemical indus- 

 tries are merely tributary to the iron and steel. 



Governing factors on which paint consistency 

 depends — pigments fiocculation one of the most 

 important: Henry Green. The governing factors 

 on which yield value and mobility depend are the 

 viscosity of the vehicle, the pigment-vehicle ratio, 

 the force of fiocculation in the pigment-vehicle 

 system and particle size of the pigment. As the 

 force of fiocculation in the pigment is the most 

 important of -the four factors, it is studied in 

 detail. The paper contains much valuable infor- 

 mation pertaining to paint manufacture. 



Constants of rosin change after powdering: 

 E. P. Veitch and W. F. Sterling. Samples of 

 various grades of rosin were powdered and kept 

 in stoppered bottles. Analyses at the start and 



