In order to assess the relative electronic effects of the 1-methyl and “1,8-dimethyl” groups and of the acenaphthene bridge in the naphthalene series, the following amines and theiri N,N-dimethyl derivatives have been prepared: 4-methyl-1-naphthylamine, 4-methyl-2-naphthylamine, 4,5-dimethyl-1-naphthylamine, 4,5-dimethyl-2-naphthylamine, 5-acenaphthenamine and 4-acenaphthenamine. 1-Naphthylamine and 2-naphthylamine have been purified and their N,N-dimethyl derivative prepared. The dissociation constants of the conjugate acids of these amines have been measured by an ultraviolet spectrophotometric method, and the results have been interpreted in terms of the electron releasing properties of the substituents. A novel reaction between trimethyl phosphate and some 2-naphthylamines has been discovered, and this has been briefly investigated.