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ing basic fundamental theory, formal methods of analysis of data, and appropriate scheduling of experiments that the professional should be able to use the statistical approach to research or production.The basic theory is presented in the first five chapters. The next four chapters are devoted to the statistical design of an experiment and the analysis of data resulting therefrom. Chapter Ten treats control charts not only from the production aspect but also as an analytical tool for the researcher. The final chapter treats of several techniques for examining admissibility of data.Undoubtedly this volume will become a standard reference book as it is exceedingly well written as to methodology. It is unfortunate that not all the confusing notation has been expunged and that the mathematics is overcumbersome. The chapter on control charts seems to suffer from a failure either to introduce the midrange and median or to discuss chart analysis of data h'om complex experiments. The treatment of tolerance limits, components of NOW! GET 10% TO 15% MORE ANODE MILEAGE WITH... NEW ANACONDA "PLUS-4" ANODES* (PHOSPHORIZED COPPER)Freedom from anode sludge--"J" no "bagging" or diaphragms required.No copper build-up ~"in solution.Exceptionally smooth, "J" heavy cathode deposits.10% to 15% more cathode "J" deposits per pound of anode.It has been discovered that carefully controlled amounts of phosphorus, together with minute amounts of other elements in electrolytic copper, make anodes of vastly superior quality for acid plating. ANACONDA "PLUS-4" Anodes are available in all the standard sizes and forms at no increase in cost over ordinary anodes. Look for the stamp "Pnus-4" on the anodes you buy.We'll be glad to supply additional information, in detail, without obligation. Just write to: The American Brass Company, Waterbury 9.0, Connecticut. ~4~5~ *For use under Patent No. 2,689,216

IIIo IV* Values of k s Obtained with a Hanging Amalgam Drop for the Reaction Cd** + 2e" = Cd(Hg) at 0°C Electrode Coverage versus Concentration of Adsorbate for Adsorption on Mercury at 30°Co and =0*^1 Volts (vs0 S oC o E 0) in 1.0 M Tartaric Acid and 0.1 M Sodium Chloride Data for Fig. 10

Variations of overvoltage for oxygen evolution from one metal to another primarily result from variations in the energy of the bond M–OH. The overvoltage decreases approximately in a linear manner with increasing bond energy. This relationship is verified experimentally for Ag, Au, Cd, Co, Cu, Fe, Ni, Pb, Pd, and Pt, for electrolysis in one N potassium hydroxide at one amp cm—2; the experimental data are those reported by Hickling and Hill. Bond energies for M–OH are calculated by three different thermodynamic cycles involving, respectively, the standard heat contents of the hydroxide, the oxide, and spectroscopic data for molecules MO. Variations of the energy of the bond M–OH, as the electrode is oxidized to a higher valence, also account for sudden breaks in plots of overvoltage against logarithm of current density. Finally, there is essentially no correlation between the oxygen overvoltage for different metals and the corresponding work functions.

HggClg, (Cl-) = 1. This value at 30' was evaluated by graphical extrapolation of the e.m.f. values for the cell Hg I HggC12, HCl 1 Hz a t 30" derived from the data of Ellis4 and Eo was the required potential of the molybdenum system referred to the standard hydrogen electrode. q 0.2 I I 4. 0 1.0 2.0 Fig. 4.The equation for the relationship between E and EO can be rearranged asThe values for the left-hand side of this equation are plotted against 1/1; on the curve shown in Fig. 4. From the plot it becomes clear that graphical extrapolation can lead to a reliable limiting value for E6 which was found to be 0.2145 v. This gave EO = 0.2145 + 0.2680 = 0.4825 v. which agrees very well with the value 0.4826 v. obtained against the hydro. gen electrode. The fact that the set of oxidationreduction potentials below 3 N acid, when plotted against fi, lie on a straight line which can be extrapolated to zero ionic strength, permits the evaluation of Eo if it is assumed that the profound effect of hydrochloric acid on the molybdenum ions would vanish at infinite dilution. However, in the absence of any other evidence as to.the species of molybdenum ions present in solution at zero acid concentration, it is necessary to be very cautious with regard to designation of the extrapolated value as a true standard potential of the Mo(V1)-Mo(V) system.A theoretical treatment of irreversible oscillographic waves is developed for the case of a linear variation of the electrode potential. This treatment is based on the following hypotheses: 1. The rate of electron transfer is proportional to the concentration of the substance reacting at the electrode surface. 2. The rate of electron transfer is an exponential function of the electrode potential. The boundary value problem is solved by expressing the concentration of reacting species at the electrode surface in terms of the flux of this substance at the electrode surface, and by solving the resulting integral equation.The current-potential curve exhibits a peak whose height is proportional to various factors among which the most important are: the concentration of reducible substance, the square root of the rate of potential change, the number of electrons involved in the over-all electrochemical process, the square root of the transfer coefficient, and the square root of the number of electrons involved in the rate-determining step. The potential corresponding to the peak of the wave is calculated, and it is shown that this potential is a function of the rate of potential change. The theoretical conclusions are in good agreement with experimental data for the reduction of zinc tetrammine ion. Some features of the oscillographic method in which the anodic wave is recorded immediately after the cathodic wave, are also discussed.