30 FRUIT AND KITCHEN GARDEN. 



and embryo fruit from the hoarfrost, an ^ when danger is 

 past are removed to give free access to the genial showers 

 and sunshine of summer and autumn. 



Hot Walls. A considerable proportion of the walls of 

 every good garden, especially in the north, should be con 

 structed with flues to supply the means of applying arti 

 ficial heat. The additional expense is trifling; and, in 

 cold seasons and cold situations, the aid of this species of 

 wall is nearly indispensable for the regular ripening of 

 grapes, apricots, and figs, as exemplified at Erskine House 

 on the Clyde, where, with the assistance of a little fire- 

 heat, large and high-flavored black Hamburgh grapes are 

 produced, and where Mayduke cherries have been ripened 

 at &quot;least six weeks before the usual period. The application 

 of fire-heat for a few weeks in spring will secure the setting 

 of the fruit, and the same operation continued for a short 

 time in autumn will suffice to ripen it, and also to prepare 

 the young wood for the next year. The flues may be about 

 twenty inches deep, and should make as many horizontal 

 turns as the height of the wall will permit. One furnace 

 will be enough for a surface fifty feet in length. When 

 the boundary walls do not furnish room sufficient for the 

 production of the finer fruits, cross walls are built athwart 

 the garden from east to west, of the same height as the side 

 walls, to which they nearly approach. They are generally 

 flued, and are sometimes furnished, on their southern 

 aspect, with sloping glazed frames, either fixed or movable. 

 These cross walls add greatly to the capabilities of a fruit- 

 garden, and are useful in affording additional shelter to the 

 small fruits and crops of vegetables in the culinary quarters. 



Espalier-Rails. Subsidiary to walls as a means of train 

 ing fruit-trees, espalier-rails were formerly much employed, 

 and they still prevail in many parts of England. In their 



