346 



SCIENCE 



[N. S. Vol. XXXIII. No. 844 



The maximal work which is obtainable from a 

 chemical reaction in a reversible cycle is cal- 

 culable by the second law of thermodynamics, 

 but this law, it is explained, can be more gen- 

 erally expressed by substituting the intensity 

 factor by an equivalent energy factor, in which 

 latter form, as was shown in a former paper, it 

 is more applicable for energy conversion with 

 saturated vapor than the former. It is now 

 shown that the new version is also well adapted 

 to chemical energy conversions, and that it fur- 

 nishes veiy simple arithmetic expressions for the 

 solutions of the problems involved. 

 Nucleation of Mixed Vapors in Dust-free Air: 



I. H. Derby. 



The expansion ratios necessary to produce, in 

 dust-free air, the formation of rain and fog, 

 respectively, in mixed vapors of alcohol and water 

 and mixed vapors of methyl alcohol and water 

 have been determined for each pair of substances 

 at varying concentrations. The series of ratios 

 for each pair of substances show a minimum 

 value for certain mixtures. 



A tentative explanation of this behavior rests 

 on the assumption that the molecules of one sub- 

 stance act as nucleation centers for the vapors 

 of the other, due to the fact that the vapors of 

 alcohols are charged with electricity opposite in 

 kind to that found in water vapor. 

 The Rapid Determination of Silver and Cadmium 



iy Means of the Gauze Cathode and Stationary 



Anode: R. C. Benner and W. H. Koss. 



The study of the efficiency of the gauze elec- 

 trode with a stationary anode as a rapid means 

 for the deposition of the metals was extended to 

 include silver and cadmium. Satisfactory results 

 were obtained for each metal by using an elec- 

 trolyte consisting of potassium cyanide in a 

 potassium hydroxide solution. White adherent 

 deposits were uniformly obtained in this manner. 

 Good results, however, were not obtained when 

 using any of the electrolytes commonly recom- 

 mended for the older electrolytic methods. 

 The Rapid Deposition of Cobalt and Nickel hy 



Means of the Gauze Cathode and Stationary 



Anode: R. C. Benner and W. H. Ross. 



A study was made of the efficiency of the gauze 

 electrode as a rapid means of depositing the 

 metals nickel and cobalt with currents of from 

 three to four amperes. Excellent results were 

 obtained for each metal with the following elec- 

 trolytes which were used in the older electro- 

 lytic methods — ammonium sulphate, ammonium 

 acetate and ammonium formate, all in ammo- 



niacal solution. In a neutral or slightly acid 

 solution there is a tendency to anodic deposition. 

 The results obtained with ammonium oxalate 

 were not quite as satisfactory as with the other 

 electrolytes named. A number of determinations 

 were made in solutions of ammonium carbonate. 

 This formed a most satisfactory electrolyte, either 

 with or without the addition of ammonium hy- 

 droxide, from which to deposit these metals. 



The rate at which these elements are precipi- 

 tated on the gauze electrode is practically the 

 same for all electrolytes mentioned, and, although 

 not quite equal to the rate at which they can be 

 precipitated when the electrolyte is agitated by 

 mechanical means, is rapid enough for practical 

 purposes. This method is likewise much more 

 satisfactory because of the simplicity of the ap- 

 paratus and from the fact that, if desired, the 

 older methods with small currents may be used 

 with the same electrodes. 



The Function of the Walls in Capillary Phe- 

 nomena: S. L. BiQELow and F. W. Hunteb. 

 Experimental method and results were given 

 demonstrating that the capillary ascension of 

 water is measurably different in tubes of Zn, Cu, 

 Ni, Al, Ag, Pt, glass, celluloid, beeswax and 

 paraffin. From this fact the conclusion was 

 drawn that, in all cases except where the maxi- 

 mum ascension is obtained, the ascension is a 

 measure of the adhesion between the liquid and 

 the walls rather than a measure of the cohesion 

 (surface tension) of the liquid. 



The capillary ascensions of saturated solutions 

 of copper sulphate, gypsum, sodiiun chloride, 

 potassium dichromate and alum were measured 

 in tubes of platinum, of glass and of the solid 

 solute. A regularity was discovered which may 

 be stated as follows: The adhesion between a salt 

 and its saturated solution is nearly the same for 

 a number of salts irrespective of their chemical 

 nature. The paper will appear in the Journal of 

 Physical Chemistry. 



The Hydrocarbons in Lignite: G. B. Fbank- 



roRTER and A. P. Peterson. 



In this paper the hydrocarbons have been 

 studied with the idea of isolating some of the 

 heavier ones. The first work consisted in the 

 proximate analyses of the lignites from the vari- 

 ous localities, ranging from the southern to the 

 extreme northern limits of the Dakota, Saskat- 

 chewan, Alberta and Alaska lignite belts. 



An average of the distillation products in these 

 different samples was about 50 per cent, carbon 



