ORCHID-HOUSES. 



407 



on the roof ; and, when that is insufficient, 

 by a pipe from the general reservoir. 

 This house joins the camellia-house on 

 one end, and the second orchid-house on 

 the other. 



In the section fig. 558 the arrangement 

 will be seen more clearly : a a a are the 



Fig. 558. 



season, 

 heated 



flues ; d the cistern of water ; c the centre 

 or principal plant-table ; e the front table ; 

 / the back table ; g front ventilators ; h 

 ridge ventilator ; i support of ridge ; h h 

 iron rods supporting the rafters, to enable 

 them to sustain the weight of plants 

 suspended from them ; I back ventila- 

 tion, — the cold air entering the house 

 close to the floor level. This house 

 is roofed with rafters and sashes, placed 

 here as being the most trying situa- 

 tion as regards the decay of material. 

 These rafters, considerably reduced in 

 size, and the sashes re-glazed, are the 

 same which formed the vineries in the 

 old garden at Dalkeith ; they were made 

 in London about the year 1762, and 

 brought to Scotland in a vessel freighted 

 on purpose; and such is the state of 

 the wood-work at the present day, 

 that we predict they will last longer 

 than any of the houses built by our- 

 selves of new material within the last 

 ten years. The plants are set on plat- 

 forms of open wood-work, to admit of 

 the free circulation of both heat and 

 air around them, as well as to keep 

 the roots moderately dry ; for we are 

 not of those who cultivate plants, the 

 majority of which grow naturally sus- 

 pended from the stems and branches 



of trees, on shelves of stone flooded with 

 water. The front ventilators g are built in 

 the front parapet wall in the usual man- 

 ner ; the ridge ones are lids which lift 

 up and down, and are operated upon by 

 means of a rod to push them up, and 

 a line to pull them down. We intro- 

 duced smoke-flues into this house, having 

 built it in haste towards the end of the 

 intending afterwards to have 

 tank in the centre, and 

 hot-water pipes 

 round the sides. 

 It, however, works 

 so well, that we 

 see no reason for 

 altering it ; and 

 were it not that 

 there is the usual 

 trouble and dirt at- 

 tending the clean- 

 ing of the flues, we 

 would be quite 

 satisfied with it as it stands. The length 

 of this house is 52 feet, breadth 22 feet, 

 and height 1 1 feet from the floor to the 

 ridge. 



Fig. 559 is the ground-plan of another 

 orchid-house in the same establishment 



Fig. 559. 



as it was till very recently arranged. As 

 will be seen, it is heated by hot-water 

 tanks, which have already been described, 

 (vide section Flues.) Over the tanks, 

 which were covered with Welsh slates, 

 were arranged the plants, but elevated 4 

 inches above the slates on wooden trellises, 

 as shown in section, fig. 560. Ventila- 

 tion is effected by wooden box-ventila- 



