NEWTON AND THE COMPOSITION OF LIGHT Galileo, that giant in physical science of the early seventeenth century, died in 1642.

On Christmas day of the same year there was born in England another intellectual giant who was destined to carry forward the work of Copernicus, Kepler, and Galileo to a marvellous consummation through the discovery of the great unifying law in accordance with which the planetary motions are performed.

We refer, of course, to the greatest of English physical scientists, Isaac Newton, the Shakespeare of the scientific world.

Born thus before the middle of the seventeenth century, Newton lived beyond the first quarter of the eighteenth (1727).

For the last forty years of that period his was the dominating scientific personality of the world.