In designing Hill Gardens, the hillocks should first be arranged, and then the water channels; the principal rocks and stones are next distributed, and lastly the trees and shrubs are planted. When constructing garden hills, in lake gardens, it must be remembered that their bases will be partly immersed after the water has been let into the adjacent lake or river bed, and an allowance in altitude must be made on this account. A good average proportion for such eminences is that of a height equal to one half of their breadth at the base. But this is not absolute, distant hills being designed higher, and nearer hills lower, in proportion to their widths. Sharp broken edges to hills are carefully avoided. If the site already possesses fine clumps of trees, the arrangement of stones may be subjected to such conditions; but with this exception the vegetation is always disposed last, and in a subsidiary manner to the principal lithic features.