ABSTRACT
On 30 May 1953 James Watson and Francis Crick published in Nature a correct interpretation of the crystalline structure of deoxyribonucleic acid, DNA. The work that ended by making biological sense of the nucleic acids began forty years ago in the shabby laboratories of the Ministry of Health in London. The analysis of pneumococcal transformations was carried forward by Martin Dawson and Richard Sia in Columbia University and by Lionel Alloway at the Rockefeller Institute. The new conception was full of difficulties, the most serious being that the nucleic acids seemed too simple in make-up and too little variegated to fulfil a genetic function. It is characteristic of science at every level, and indeed of most exploratory or investigative processes in everyday life. The paradigm of all lucky accidents in science is the discovery of penicillin – the spore floating in through the window, the exposed culture plate, the halo of bacterial inhibition around the spot on which it fell.
