Ever since Blaschko1 first described the dermatitis associated with galvanizing, this condition has played a practical rôle in dermatology. Schittenhelm and Stockinger2 wrote that nearly every one who does this sort of work sooner or later becomes eczematous. If this is true, the condition has not only a practical importance but also an interesting theoretical aspect. Its frequent occurrence would show that nickel is one of the rare substances to which every one can be sensitized. In support of this theory, Walthard3 demonstrated that he was able to sensitize guinea-pigs regularly with nickel. This whole theory of nickel as a uniformly sensitizing substance, however, does not hold true. The experiments of Walthard3 have not been confirmed by other workers. In the investigations of Schittenhelm and Stockinger,2 it is peculiar that positive reactions to the nickel test were obtained only on areas of skin previously affected.