If the word tone, or rather tune, is to be still borrowed in future from music, and applied to colouring, it might be used in a better sense than heretofore.
For it would not be unreasonable to compare a painting of powerful effect, with a piece of music in a sharp key; a painting of soft effect with a piece of music in a flat key, while other equivalents might be found for the modifications of these two leading modes.
FALSE TONE.
The word tone has been hitherto understood to mean a veil of a particular colour spread over the whole picture; it was generally yellow, for the painter instinctively pushed the effect towards the powerful side.
If we look at a picture through a yellow glass it will appear in this tone. It is worth while to make this experiment again and again, in order to observe what takes place in such an operation. It is a sort of artificial light, deepening, and at the same time darkening the plus side, and neutralising the minus side.