There was one slight mistake in Newton's belief that all prisms would give a spectrum of exactly the same length, and it was some time before he corrected this error.

Meanwhile he patiently met and answered the arguments of his opponents until he began to feel that patience was no longer a virtue.

At one time he even went so far as to declare that, once he was "free of this business," he would renounce scientific research forever, at least in a public way.

Fortunately for the world, however, he did not adhere to this determination, but went on to even greater discoveries--which, it may be added, involved still greater controversies.
In commenting on Newton's discovery of the composition of light, Voltaire said: "Sir Isaac Newton has demonstrated to the eye, by the bare assistance of a prism, that light is a composition of colored rays, which, being united, form white color.

A single ray is by him divided into seven, which all fall upon a piece of linen or a sheet of white paper, in their order one above the other, and at equal distances.