GARDEN STRUCTURES. 



205 



bottom heat will be perfectly at command. 

 There should also be openings in the walls of 

 the chamber, to be closed by plugs or other 

 means, so that heat can be permitted to ascend 

 from the chambers into the atmosphere of the 

 house, or can be confined to the chambers at 

 will. It is also desirable to have troughs for 

 water either cast with the pipes or fixed on to 



Fig. 266.— Section of Propagating Pit. 



them, so that the air inside the chamber can be 

 kept moist. Fig. 266 shows propagating frames, 

 which are generally fixed on a bed or shelf at one 

 end of the house. 



Vineries (figs. 267 and 268). — The Vine, from 

 the flexible nature of its rods, can be trained in 

 any direction, whether parallel with the glass or 

 not, and either upwards, downwards, obliquely, 

 or horizontally; and in any of these ways good 

 crops may be obtained, provided the foliage is 

 not too far from the glass. As a good border 

 is generally afforded, the length of shoot made 

 in a season is considerable; and if the Vinery is 

 of limited extent that form is the best which 

 admits of the greatest length of shoot being 

 trained so as to enjoy the greatest amount of 

 light, and as nearly as possible an equal degree 

 of temperature as regards the bottom and top 

 of the plant. 



Vineries are generally, and we think most 

 properly, built so that their front may present 

 a southern aspect; either one directly south, or 

 inclined to the south-west, in order to be acted 

 on with the greatest possible effect by the sun's 

 rays. Doubtless some will object to this on 

 account of scorching; but even the purest glass 

 acts more or less as a screen, in passing through 



which the sun's rays are not so intense as they 

 are when they strike upon objects freely ex- 

 posed. There is, of course, an exception to this 

 when the glass is not plane, for the rays would 

 be more or less concentrated by convexities; 

 but we may rest assured that healthy vines will 

 not be injured by the sun's rays passing through 

 plane glass, if sufficient ventilation is afforded. 

 The size of a Vinery must be 

 determined in a great measure by 

 the means at command, not only as 

 regards the first cost of erection, 

 but also that of future keeping 

 and management. We have seen a 

 considerable amount of produce in 

 a very small house, not more than 

 10 feet long and scarcely so much 

 in breadth, and in such a space it 

 is possible to ripen well 50 lbs. of 

 Grapes, and even more than that 

 with good management. "With ample 

 means, on the contrary, the length 

 may extend to hundreds of feet in 

 one range; but the range ought to 

 be divided by glazed partitions, and 

 in very few cases should the divi- 

 sions exceed 50 feet in length. By 

 means of these divisions we can give 

 the proper treatment to early or late 

 crops, as well as to kinds requiring much or 

 comparatively little heat. The width need not 

 exceed 15 feet, and this will admit of nearly 

 20 feet of training. 



The height of the front wall is the next con- 

 sideration. W r here there are no upright front 

 sashes, the front wall should not be more than 

 1 foot above the level of the border, making 

 allowance for this being raised above the general 

 level of the surrounding area. If there are front 

 sashes, they should not be high, otherwise the 

 extent of surface for training the rods of the 

 Vines is diminished. The height of the back 

 wall depends entirely upon the Avidth of the 

 house and the angle which the roof is to form 

 with the horizon. This should be considered 

 with reference to what has been stated on that 

 subject ; it may be from 30° to 34° for the 

 general crop in the south of England and near 

 London, and a degree more for every degree of 

 latitude farther north. For very early forcing 

 it may be 40°. 



The Span-roof answers best for late Grapes: 

 not that span-roofed houses are the best for late 

 Grapes under all circumstances, but this form is 

 better for them than for those requiring to be 

 forced. As a rule, whatever may be its form, 



