Landscape gardening for unity, variety and harmony

To illustrate the three principles, with reference to Landscape Gardening, we may remark, that, if unity only were consulted, a scene might be planted with but one kind of tree, the effect of which would be sameness; on the other hand, variety might be carried so far as to have every tree of a different kind, which would produce a confused effect. Harmony, however, introduces contrast and variety, but keeps them subordinate to unity, and to the leading expression; and is, thus, the highest principle of the three.