"Whether Newton saw the lines or not, he seems to have paid no especial heed to them. In the year 1802, Dr. W. H. Wollaston using, a slit one-twentieth of an inch in width, noted at least four fine dark lines crossing the solar spectrum. Supposing them to be merely 'natural boundaries' of the different colour-bands, he too inquired no further; and there still for a while the matter rested. Nobody yet suspected, even vaguely, what great future results lay enfolded in the casual discovery of these few slight lines. Not many years later the matter was taken up by Fraunhofer, an able German optician."