In the first place, I require of him that he should be able to read French and Italian with tolerable facility, and that he should speak them both a little. He ought to understand well the orders of architecture, so as to be able to sketch any one correctly without reference to his books, and to be acquainted with their varieties in the principal published examples. He must have been accustomed to draw, from casts or from the stone, the usual architectural ornaments, and particularly the Corinthian capital; making of them plans, elevations, sections, and views: every thing necessary in order completely to understand them himself, and to enable him to explain them to others. I say nothing of his ability to take the general plans, &c. of buildings, because I consider it as a matter of course. He should be capable of representing these ornaments justly, not only on flat, but also on curved surfaces, as for instance, on a vault or a dome; and this not only geometrically, but also in perspective, and he must understand exactly the forms assumed in perspective by the different curves of the Doric capital, and of the Attic base, and the effect of light and shade upon them: a subject perhaps, in spite of its extreme simplicity, more difficult to manage than the Corinthian capital. All these seem to be absolutely necessary to facilitate the correct understanding and delineation of the objects he may meet with on his journey; and their effects, both as single objects, and in combination with other parts and accompaniments. Let me add, that if he had at least attempted to model some of them, it would be a great advantage to him, as this act requires a still more precise acquaintance with form, than even the correct drawing. He should also be able to sketch landscapes and figures; not as a professed painter or sculptor, but enough to explain the effect both of situation, and of the addition of statues and bas-reliefs; and to form at least a scale to his drawings, by the introduction of living objects.