Scientific Public Gardens. 657 



the paltry walk which diverges from it to the left, at its farther 

 end ? The terrace itself, indeed, is an absurdity, because it in no 

 way adds to the effect of the garden : it is merely a broad level 

 walk, which might be placed any where ; whereas so conspicuous 

 a feature ought to have had the appearance of being determined 

 by existing circumstances, or forming an essential part of the 

 general design. The planting of these Zoological Gardens is 

 in every respect as badly designed as the walks, and for it, 

 indeed, there is the same excuse ; but, as a proof that the subject 

 of planting is not at all understood by those who have laid out 

 the additions lately made to this garden, we need only refer to 

 the spotty heterogeneous mixture already pointed out. (p. 458.) 



Botanical Gardens, Horticultural Gardens, and Agricultural 

 Gardens, we shall at present pass over. Our plan for the Birming- 

 ham Botanical and Horticultural Garden, given in Vol. VIII. 

 p. 410., we conceive to be a very good example of the manner in 

 which a botanical, a horticultural, an agricultural, an arbori- 

 cultural, and an ornamental garden may be united ; and, though 

 the garden actually executed is a miserable failure, our design 

 will remain to show what it might have been. 



An Arboretum generally forms a part of a botanic garden, but 

 no arboretum has hitherto been planted in any country, with the 

 exception of the one commenced by the Duke of Devonshire at 

 Chatsworth, in which ample room is allowed for the trees to 

 attain their full size. A remedy for this evil will probably be 

 found in the planting of arboretums as distinct public gardens, 

 either belonging to corporations, or to private associations or in- 

 stitutions. The space required for an arboretum, to allow all 

 the species and varieties of trees and shrubs, foreign and do- 

 mestic, now in the country, that will stand the open air in the 

 neighbourhood of London, to attain their full size, will not be 

 less than from 100 to 150 acres; but much, as we have already 

 observed (p. 386.), may be done in 10, 20, or 30 acres; and we 

 hope that arboretums to this" extent will sooner or later be esta- 

 blished, as part of the public gardens of all our large towns. In 

 some, indeed, the entire garden, park, or promenade may be 

 planted as an arboretum. In short, in all public gardens what- 

 ever, unless there be some specific reason to the contrary, it 

 would contribute greatly to their interest and beauty, if never 

 more than one specimen of each kind of tree and shrub were 

 planted ; unless there were room for duplicates, triplicates, or 

 more, which, in that case, should be placed all together. 



An arboretum may be arranged in either of the three modes 

 before mentioned ; viz. geographically, geologically, or scienti- 

 fically. Where the surface is flat, and the soil and climate uni- 

 form, or nearly so, some scientific mode will be found preferable ; 

 but where the soil and surface are exceedingly irregular, a geo- 



VoL. XL — No. 69. 3 b 



