SYNTHETIC compounds possessing specific curative effects in various infections -‘chemotherapeutic agents’ as they are termed-have long been sought for, though without much success, at least in bacterial infections. Three years ago, ‘Prontosil’, a sulphon-amide compound, proved valuable in the treatment of streptococcal infections, such as puerperal fever. Quite recently, L. E. H. Whitby, investigating experimentally a number of synthetic compounds, found that one of them, ‘M. & B. 693’, had a marked specific effect upon the pneumococcus, the microbe of human pneumonia, almost complete protection being afforded against Types i, vii and viii pneumococcus infections, and a high degree of protection against Types ii, iii and v (Lancet, 1, No. 22, 1210; May 28, 1938). Encouraging clinical results in cases of pneumonia in man were reported by Evans and Gaisford (Lancet, 1, No. 23, 1305; June 4, 1938), and Telling and Oliver now give details of another case treated with this agent (Lancet, l,No. 25, 1391; June 18, 1938). The patient, an old lady, was critically ill with pneumonia, pneumococcus Type iii being recovered from the sputum. After four days' treatment with the drug, recovery commenced and was finally complete. The observation was made that, in the course of treatment, the capsule which surrounds the pneumococcus became lost, and other changes in the organism were apparent.M. & B. 693', chemically, is 2-(p-amino-benzenesulphonamido) pyridine.