■818 



SCIENCE. 



[N. S. Vol. XXI. No. 543. 



R. R. Ramsey, University of Indiana : ' Polar- 

 ization of Standard Cells.' 



Henry Crew and B. T. Spence, Northwestern 

 University : ' Variation of Arc Spectra with the 

 Phase of the Current Producing Tliem.' 



A. A. MiCHELSON, University of Chicago : ' Re- 

 ciprocal Relations in Diffraction.' 



A. A. MiCHELSON, University of Chicago : ' Re- 

 port of Progress in Ruling Diffraction Gratings.' 



A. A. MiCHELSON, University of Chicago : ' On 

 the Use of the Concave Mirror with Diffraction 

 Gratings.' 



N. A. Kent, Wabash College: 'The Relative 

 Positions of the Arc and Spark Lines in the 

 Spectra of Titanium and Zinc' 



H. M. Reese, University of Missouri : ' The 

 Resolving Power of Quartz Prisms.' 



E. S. JoHONNOTT, Rose Polytechnic Institute: 

 ' The Black Spot in Thin Liquid Films.' 



F. L. Bishop, Bradley Polytechnic Institute: 

 ' Thermal Conductivities.' 



A. P. Carmen, University of Illinois : ' The 

 Collapse of Tubes by External Pressure.' 



A. B. Porter, Chicago: 'Abbe's Diffraction 

 Theory of Microscopic Vision.' 



F. R. Watson, University of Illinois : ' Surface 

 Tension by the Method of Liquid Jets.' 



A. L. Foley and J. H. Haseman, University of 

 Indiana: 'Diffraction Fringes of Electric Dis- 

 charges and the Fluid Streams.' 



L. T. More, University of Cincinnati : ' On 

 Dielectric Strain Along the Lines of Force.' 



J. E. Almy, University of Nebraska : ' On the 

 Dielectric Strength of Crystals.' 



Pekcival Lewis, University of California : 



' The Velocity of Ions in Gases from Colored 

 Flames.' (By title.) 



L. R. Ingersoll, University of Wisconsin : ' Tlie 

 Kerr Effect in the Infra-Red Spectrum.' 



E. L. Nichols and Ernest Merritt, Cornell 

 University : ' The Phosphorescence of Sidot Blend.' 



W. W. Coblentz, Cornell University: 'Infra- 

 Red Emission Spectra of Gases in Vacuum Tubes.' 

 (By title.) 



D. B. Brace, University of Nebraska : ' Jither 

 Drift and the Rotary Polarization Test.' 



D. B. Brace, University of Nebraska : ' On a 

 Test of Anomalous Dispersion by Means of 

 Channeled Spectra.' 



C. B. Thwing, Syracuse University: 'Experi- 

 ments on the Flow of Electricity in Metals under 

 Changes of Pressure.' 



H. A. Clark, University of Nebraska: 'The 

 Absorption and Refraction of Carbon.' 



Ernest IVrKHKiTT, 



Secrefa7-y. 



AMERICAN CHEMICAL SOCIETY. 

 NEW YORK SECTION. 



The sixth regnlar meeting of the New York 

 Section was held Friday, March 10, at 8:30 

 P.M., in the American Museum of I^atural 

 History, 78th Street and Central Park West. 



The program of the evening was as follows : 



The Vapor Friction of Isomeric Ethers : Mor- 

 ris LoEB and F. S. M. Pederson. 

 The recorded experiments on the friction of 

 vapors, by the transpiration method, having 

 been made with cumbersome apparatus and at 

 the temperature corresponding to the boiling 

 points of the substances, it was thought im- 

 portant to devise a method whereby non-sat- 

 urated vapors could be studied at identical 

 temperatures, for the purpose of ascertaining 

 whether the constitution as well as the com- 

 position of organic compounds influences the 

 molecular volume, of which the vapor-friction 

 is a function. 



The apparatus used consists of a U-tube, 

 one limb of which, about 60 cm. long, has a 

 bore of less than one tenth of a millimeter, 

 while the bend and the other limb is just wide 

 enough to allow a column of mercury to de- 

 scend unbroken. A stop-cock and funnel-end 

 are placed on the wider tube, which also bears 

 two marks about 50 cm. apart. The capacity 

 of the tube between these marks is accurately 

 determined. The whole apparatus can be 

 heated uniformly, as it is surrounded by a 

 vapor-jacket. Before heating, the liquid to be 

 studied is poured into the tube and is vapor- 

 ized as the temperature rises, in such a man- 

 ner as to expel all air and foreign gases. A 

 short column of mercury, of known length is 

 introduced by means of the stop-cock, and in 

 its descent forces the vapor through the cap- 

 illary; the time in which the lower meniscus 

 travels from the upper to the lower mark is 

 ascertained by means of a stop-watch. The 

 method is easy and rapid, and experiments 

 with air gave results agreeing well among 

 themselves and with the values obtained by 

 the majority of previous observers. The cal- 

 culations were made according to Poiseiille's 

 formula, very few corrections being necessary. 



From the study of isomeric ethers, as well 

 as ethyl alcohol, it was found that the consti- 



