394

tag will prevent it from being included in many personal libraries. It repre- sents a massive effort by the editor and authors for which they are to be commended. Its greatest fault is too little background information in a few chapters whereas in some other chapters less background would htive been in order considering the large amount of already published information in these cases. It is a book for the professional more than the student. The subject and author indices seem very adequate.

D.R. PAUL Department of Chemical Engineering The University of Texas at Austin Austin, TX 78 712

Erratum

J. Membrane Sci., Vol. 2, No. 3 (September 1977)

Page 259, eqn. (35) should read

RT -A@ =pln

2F i

+ and further as printed