Abstract
Sub-spectral, direct and perturbation techniques have been applied in the analysis of the N.M.R. spectrum of pyridine. The results are compared with those obtained by the iterative method. A close agreement between the two is found. The negative coupling constant J XX′ is confirmed directly by identification of the symmetry species of the abc-type sub-spectra by use of tickling. Limitations of the direct method of analysis are discussed.