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measurement, which makes the correction factor rather uncertain.The influence of end-effects (zlZ-effects) on the results of the capillary method has recently been discussed by several authors. BOCKRIS et al. 7 claim that it is impossible to avoid zl/-errors even if the flow rate past the capillary mouth is carefully chosen. According to SPEDDING and MILLS 8 , on the other hand, the Al error will be negligible for certain flow rates. Since the investigation by DWORKIN The above results show, that the paper strip technique can be used for self-diffusion measurements in molten salts if a correction for the exchange of metal ions between the glass and the melt is applied when necessary. The glass-melt interface is very large, and this fact, in conjunction with the comparatively long diffusion times that are needed, enhances the exchange. (A somewhat similar situation is encountered in the porous frit technique 2 ' 3 , but the corresponding problem is by no means so serious, since the diffusion times are of the order of 30 minutes only.) Due to the difficulty to determine the correction factor accurately, the paper strip method is not capable of the highest precision. It is, on the other hand, very simple to use, and it is able to give valuable independent checks of the results of other methods. This work has been financially supported by "Adlerbertska Forskningsfonden", which is gratefully acknowledged. Thanks are due to Mr. W. PARKER for making the radioactive samples. The thermocell Ag(7 , 1)/Ag2 S04/Ag(r2) has been studied over the temperature range 420 to 750 °C. The results can be described by the following linear relations 1 -£1= (0.31 ±0.01) mV/°C (657-750 °C) --£s= [(0.687 + 0.011) -(0.472 + 0.019) -10 3 -mV/°C (420-657 °C) £1 and £s are the SEEBECK-coefficients of molten silver sulphate and the a-modification, respectively, and tm is the mean temperature of the salt column in °C. Thermoelectric Power of Molten and Solid Silver SulphateThe standard deviation of es was 4.3 • 10 -3 mV/°C. The transported entropy of the silver ion and of the sulphate ion have been calculated. A discontinuous change of the emf and the transported entropies was found at the melting point.

NOTIZEN 1081erfüllt, wobei A und B mit wachsendem Sn-Gehalt zunehmen. Das von R u s s e l l und J a f f r e y mitgeteilte Ergebnis 1 der Tem peraturabhängigkeit der Streck grenze bei der Zinnbronze mit 3,2 At.-Proz. Zinn, die vergleichbare K orngröße besaß, ordnet sich gut diesen Resultaten ein.Weitere Einzelheiten unserer Untersuchungen werden an anderer Stelle zusammenfassend mitgeteilt und diskutiert. In recent years thermoelectric powers of liquid metals have become of considerable interest. This is specially the case in England, where Z im a n ' s theory of electrical properties 1* 2 has initiated new measurements 3> 4 in order to get more accurate data on thermoelectric powers. (The experimental and theoretical situation regarding the electronic pro perties of liquid metals has recently been reviewed by C u s a c k 5.) Recent measurements have also been reported from other countries 6' 7. An attempt in our laboratory to use liquid zinc alloys as reversible electrodes for ionic conductors 8 initiated a study of the thermoelectric power of liquid zinc. The T herm oelectric Pow er o f Liquid ZincA cell of Suprem ax glass, Fig. 1, was used for m easuring the thermoelectric power £zn,w of the cell W /Zn/W over the tem perature range 465 -711 °C. The results are plotted in Fig. 2. «zn,w is positive9. The absolute therm oelectric power of tungsten, 5 w » is known for the tem perature range in question l0, 9 This is according to the sign convention that £a , B is posi tive when the current goes from A to B at the hot junction. This convention is used in recent work on metals 1-5. How ever, the opposite convention is very common, cf. e. g. L a n d o l t -B ö r n s t e i n , Zahlenwerte und Funktionen (6th Ed.) II :6 p. 929. In an attempt to follow other workers in the two fields, we are thus using opposite sign conventions for metals (this paper) and for electrolytes (see 8 and A. K v i s t and A. R a n d s a l u , Z. Naturforschg., in press). 10 N. C u s a c k and P. K e n d a l l , Proc. Phys. Soc., Lond. 72, 898 [1958].