S2 GARDEN MANAGEMENT. 



placed a foot from the wall receives 1° of heat from it, at one inch it wij J 

 receive heat equal to 144°. The reflection, also, of all unabsorbed rays imping- 

 ing on the surface of the wall, greatly increases the temperature of the air in 

 immediate contact with it. Besides this power of absorbing heat, moisture is 

 also absorbed, both from rain and from the atmosphere, and, with the heat, is 

 given out b}' radiation, tempering the atmosphere during the night : a wall 

 is thus, in every sense, a source of protection ; and it is of considerable 

 importance that its height and form, as well as its workmanship and mate* 

 rials, should be well considered. 



191. The countries of southern Europe, and especially Italy, can dispense 

 with some of the conservative properties of the wall, and render architecturally 

 ornamental that which we must make strictly utilitarian. The walls of 

 Italian gardens are, therefore, frequently decorated with alcoves and balus- 

 trades, with a full complement of statuary and vases. 



192. It has been already mentioned that the ha-ha fence, invented by 

 Kent, has been considered the best form of external fence ; it affords 

 protection from without, and it does not obstruct the view, but carrie? 

 the eye uninterruptedly into the neighbouring domain, while a light wire 

 fence offers the best possible protection from game and other ferm naturce. 

 A holly or privet hedge may with advantage surmount it on the east and west, 

 especially if it is intended to have outside borders, either for wall-trees 

 or vegetables : where cu'cumstances permit, a belt of trees on the north or 

 north-east side of the ha-ha will also afford a desirable shelter. 



193. Within this external fence the kitchen and fruit gardens usually form 

 a separate inclosure, more or less extensive, according to the means of the 

 proprietor ; and the wall surrounding this inclosure we have now to consider. 

 Garden walls have long been a subject for discussion, and will probably always 

 remain so : like everything else connected with gardening, they depend oa 

 local circumstances of climate, elevation, extent, and undulation. The walls 

 which would be suitable for a moderate-sized kitchen-garden, in a flat or 

 thickly- wooded country, would be very unsuitable for a loftier site, on th» 

 side of a hill, or in an open undulating country ; while a plot of small extent, 

 inclosed by walls fourteen or sixteen feet high, would be inadmissible both oa 

 artistic and physiological principles : on the first, it would seem as the walls of 

 a prison ; on the second, it would hterally be so, excluding the air, which is 

 essential to the growth of plants. 



194. On these grounds, the best practitioners consider that, for small gar- 

 dens, 8-feet walls are most suitable, provided the trees on them are planted so 

 far apart as to admit of their horizontal extension. For gardens of larger 

 size, 10-feet walls, and for an extensive garden 12, and even 14 feet, will not be 

 too great. Nicol thinks 10 or 12 feet a height convenient for pruning, water- 

 ing, and gathering the fruit, giving also ample space for the expansion of the 

 branches of most trees ; but he adds, this should be influenced by the extent, 

 or apparent extent, of the ground, the latter depending u]pon its cast: if 

 it is a lengthened parallelogram, for instance, the ground will seem larger 



