Colour is nothing but a sensation and has no existence at all independent of the nervous systems of living beings. (O.N. Rood)

Red,
green,
yellow,
blue,
white,
brown,
violet,
orange,
turquoise,
grey…
a list of colours such as this ends almost as soon as it has begun, but there are in fact twelve thousand colours in existence, like cockleshells all in a row. Twelve thousand colours. Think of it. Maybe it is not possible to tell them all apart, but they are there all the same. They exist in the catalogue of an American company which produces plastics, and their purpose is to guarantee a constant production that will always satisfy the needs of the market.

There is another American catalogue with a modest 1,200 colours, for use by commercial artists. Each colour is reproduced and numbered. This catalogue might be very useful for someone planning a large uniform edition of books, for example, or anything else for which one has to use a group of colours which correspond in tone.

How does one arrive at such a vast number of colours? There are various methods. But in the first place we must distinguish black and white from the colours proper, for black and white are no more than darkness and light. If we take, say, a sheet of green paper and look through it at the light we will see a brilliant green. Then let us take it towards a dark corner of the room, and we will watch the green grow progressively darker until in pitch blackness we do not see it at all. If you buy a set of artist’s colours it will contain tubes of black and white, but these are used only to make the true colours darker or lighter. So we may in theory set about obtaining a great number of colours in the following way: let us imagine a pure colour, say a red which contains not even the most infinitesimal quantity of yellow, blue or other colour. Take this red, which will be very like the red used by printers in four-colour printing, and paint a disc as big as a penny on a very long strip of paper. Add one drop of black to the red and paint another disc. Then another drop, another disc… and so on until the red has turned black. On the same strip, working towards the other end, paint other red discs, but this time progressively lightened by the addition of white, one drop at a time. By the time we have finished we will be extremely tired and our strip of paper will be several miles long. We can then repeat the operation starting with another red, for example with one drop of yellow added to the original pure colour. Then we start with a red with two drops of yellow added….

I am sure that you are prepared to take my word for it and not insist on making the experiment for yourselves to test me out. You will now realize that twelve thousand colours exist, even if you cannot distinguish one from its neighbour. But the story of colours does not end there. Every colour changes according to the material in which it is fixed, just as in music the same note sounds one way played on a trumpet and quite another when played on the mandolin. red silk is different from chalk of the same colour, a surface painted in tempera differs from the same painted in oils, one black velvet is blacker than another black velvet. In this case it is the roughness or smoothness of the surface which determines the variation. A smooth surface reflects the light and the colour is more intense, while on a rough surface the colour is matt and more subdued. Mrs. Jones is therefore attempting the impossible in trying to match the velvet of her sofa with her sitting-room walls, because the wall is smooth and the velvet is velvety.

Unfortunately people talk of colours too loosely, and create confusions that even those who want to be precise have to adapt themselves to. What colour is white wine? yellow. But try asking the waiter for yellow wine and all you will get is a pitying look. Do you know what colour a sheet of white paper is? Well, take quite a number of sheets, or open several books and lay them in a row. You will find that some are yellow, some brownish, others grey.

Would it be a good thing if people were taught to know their colours? I certainly think so. Any knowledge of the world we live in is useful, and enables us to understand things that previously we did not know existed.