74 



SCIENCE 



[N. S. Vol. XL. No. 1019 



the kinetic vibrational energy of the molecules is 

 just barely enough to separate them when the out- 

 side pressure (added to their own affinity) is just 

 sufficient to bring, on the average, the molecular 

 surfaces into contact. In conclusion, it is clear 

 that this interpretation of these facts is in com- 

 plete accord with the theory of compressible 

 atoms. Indeed, the various phenomena concerned 

 seemed to be thus explained better than in any 

 other way. 



The Present Status of the Absolute Staridard of 



Pressure: Theodore W. Eichaeds. 



The object of this paper was to point out the 

 fact that the absolute or C. G. S. standard of 

 pressure is being more and more used by those 

 actually having to do with the pressure-measure- 

 ment. Various meteorologists, chemists, physicists 

 and engineers are using it regularly; the United 

 States "Weather Bureau, the Blue Hill Observatory, 

 and the Weather Office in England are adopting it 

 as their method of recording atmospheric pres- 

 sures for scientific study. There is still some con- 

 flict in nomenclature, but it is to be hoped that 

 the proposal adopted by the International Con- 

 gress of Physicists, at Paris, in 1900, and inde- 

 pendently suggested by the writer, that the "ab- 

 solute atmosphere" (or the pressure of a mega- 

 dyne per square centimeter) should be called the 

 "megabar" or "megabarie, " will be generally 

 adopted. This "absolute atmosphere" is 1.3 per 

 cent, less than the old atmosphere, and is the 

 pressure exerted by a column of mercury 750.1 

 centimeters high at 45° latitude and 0° Centigrade. 



A Method for Producing a Seproducible Contact 

 Potential between Liquids: E. P. Schoch. 



The Selation between the Concentrations and the 



Potential of the Ferrous-ferric Pole: E. P. 



Schoch. (Lantern.) 

 New Electro-analytical Methods for Lead, Tin, 



Copper and Antimony: B. P. Schoch and D. J. 



Brown. (Lantern.) 

 Contribution to the Knowledge of the Actinium 



Series: Herbert N. McCoy and Edwin D. Le- 



MAN. 



Solutions of Some Formates and of Eydrogen 

 Chloride in Anhydrous Formic Acid-gases of Ap- 

 parent Agreement of Strong Electrolytes with 

 the Mass Law: H, I. Schlesinger and A. W. 

 Martin. 



When the degree of ionization of solutions of 

 sodium, of phenyl-ammonium, of potassium and of 

 ammonium formates in anhydrous formic acid is 



calculated from the conductivities of these solu- 

 tions, the values agree very closely with the equi- 

 librium law up to concentrations, varying from Q.3 

 to 0.55 molar in the several cases. These electro- 

 lytes are highly ionized in this solvent, as shown by 

 the ionization constants, which are 0.75, 0.74, 0.95, 

 1.15 for the salts in the order in which they a,re 

 named. Hydrogen chloride also agrees with the 

 law; its constant is 0.04. When the conductivities 

 are corrected for the viscosity of the solution the 

 agreement with the law is not found. 



Vapor Tensions in Alcoholic Solutions: O. F. 



TOWEE AND A. r. O, GERMANN. 



This is a continuation of the work published in 

 the Journal of the society, 1908, p. 1219. Vapor 

 pressures were measured exactly as described in 

 that paper by means of the Morley gauge. The 

 new feature is the preparation of the solutions en- 

 tirely out of contact with air. Methyl and ethyl 

 alcohols were used as solvents, and, after being 

 purified and then fractionated in vacuo, were dis- 

 tilled directly on to the solute. Potassium iodide, 

 lithium chloride, benzil and tetramethylammonium 

 iodide were the solutes employed. Curves drawn 

 with the concentrations as abscissas and the low- 

 ering of the vapor tension as ordinates are fairly 

 regular, those of the salts rising more rapidly 

 with the increase in concentration than those of 

 the organic solutes. The molecular weights of the 

 latter, as calculated, are approximately normal, 

 while those of the salts are about one half the 

 formula value and do not vary much with the con- 

 centration. The work is being continued to see 

 whether this last statement is confirmed by further 

 experiments. 



Arsenions Oxide as a Starting Material in Acidi- 

 metry: Alan W. C. Menzies and F. N. Mc- 

 Carthy. 



Equilibria in the Systems, Water, Acetone and In- 

 organic Salts: Geo. B. Frankexirter and Lil- 

 lian Cohen. 



An investigation is made of the isotherms at 

 20° of the systems, water, acetone salts. The salts 

 used are KF, K3CO3, CaCl; and NaCl. The com- 

 parative efficiency of these salts in "salting" out 

 acetone from an aqueous solution is determined. 

 KF is the most and NaCl is the least efficient. 

 The amount of acetone present in an aqueous solu- 

 tion can be determined by the formation of layers 

 when the potassium fluoride is added to the solu- 

 tion. Within certain limits methyl alcohol acts as 

 if it were water and will not interfere in this de- 

 termination. 



