Such are the principles upon which the ocular harpsichord was founded; but though the instrument, from its singularity, excited great attention when it was first constructed, we have not been able to learn that it was ever supposed to possess the power of affording pleasure to the eye. It must be obvious, indeed, to any person who considers the subject, that colour, independent of form, is incapable of yielding a continued pleasure. Masses of rich and harmonious tints, following one another in succession, or combined according to certain laws, would no doubt give satisfaction to a person who had not been familiar with the contemplation of colours; but this satisfaction would not be permanent, and he would cease to admire them as soon as they ceased to be new. Colour is a mere accident of light, which communicates richness and variety to objects that are otherwise beautiful; but perfection of form is a source of beauty, independent of all colours; and it is therefore only from a combination of these two sources of beauty that a sensation of pleasure can be excited. Those who have been in the habit of using a correct Kaleidoscope, furnished with proper objects, will have no hesitation in admitting that this instrument realizes, in the fullest manner, the formerly chimerical idea of an ocular harpsichord. The combination of fine forms, and ever-varying tints, which it presents in succession to the eye, have already been found, by experience, to communicate to those who have a taste for this kind of beauty, a pleasure as intense and as permanent as that which the finest ear derives from musical sounds. An eye for admiring and appreciating the effect of fine forms, seems, indeed, to be much more general than an ear for music; and we have heard of many cases where the tedium of severe and continued indisposition has been removed, and where many a dull and solitary hour has been rendered cheerful, by the unceasing variety of entertainment which the Kaleidoscope afforded. In one respect, indeed, this instrument is superior to all others. When it is once properly constructed, its effects are exhibited without either skill or labour; and so numerous are its applications, and so inexhaustible its stores, that the observer is constantly flattered with the belief that he has obtained results which were never seen before, and that he has either improved the instrument, or extended its power, by new applications.