The commoner hypertensive amines are derivatives of /3-phenylethylamine, that is, compounds containing the aromatic nucleus separated from the amino group by two carbons of an aliphatic side chain; e. g., tyramine HOC6H4CH2CH2NH2, epinephrine, (HO)2C6H3CHOHCH2NHCH3, and ephedrine, C6H5CHOHCH(NHCH3)CH3, all have this common structure.Recorded pharmacological studies with compounds in which the relative position of these two functional groups is modified are rare.Barger and Dale,1 in their classical study on the relationship between chemical structure and sympathomimetic action, included a series of compounds in which the relative position of the amino portion with respect to the phenyl group varied. They found that aniline has no specific action; benzylamine gives a trace of the desired activity, -phenylethylamine is feebly active, /3-phenylethylamine highly active and most active of the series, while -phenylpropylamine, C6H5CH2CH2CH2NH2, is again much less effective. While no allowance was made for any influence on the physiological activity that might be produced by the successive lengthening of the side chain, they nevertheless advanced the conclusion that "the optimum constitution of a fatty-aromatic amine for the production of sympathomimetic action is, therefore, that which is found in adrenaline itself, viz., a benzene ring with a side chain of two carbon atoms, of which the second bears the amino group."Concerning the value of the two-carbon side chain these conclusions must, in the light of recent findings, be amended, for it has been amply demonstrated that amino alcohols of the ephedrine type, that is, compounds with three carbons in the side chain, are not only very active pharmacologically but may even possess physiological and therapeutic virtues not resident in the corresponding compounds with but two carbons.2 1 Barger and Dale,