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THE FLOWER GROWER'S GUIDE. 



end to the kinds requiring the most heat, and the cooler and more airy part to 

 the rest. 



Forms of Greenhouses. 

 Greenhouses may be either span-roofed, three-quarter span, or lean-to, according to 

 circumstances. Span-roofed structures with glazed sides and ends are the most favoured 

 by professional gardeners and experienced amateurs, whilst they are the best that can 

 be erected as tenants' fixtures. They are also largely constructed by growers of plants 

 and flowers for market, these skilful cultivators being, as a rule, averse to bricks and 



Fig. G2. Laege Span-Roofed Greenhouse. 



mortar — especially high back walls. In each and every case span-roofed greenhouses 

 can be recommended for their lightness and serviceability. 



A commodious structure of the kind under notice, 18 feet wide, 12 feet high at the 

 ridge, and 5 feet high at the eaves, is represented by Fig. 62. All the working details 

 and interior arrangements, also the amount of hot-water piping needed for a greenhouse 

 of that description, are so plainly shown that little further description is necessary. 

 Houses of this style may be from 30 feet to 100 feet or more in length, and should be 

 fitted with a crank and lever apparatus for opening and closing both front and top venti- 

 lators at will or without any special effort, A house similarly constructed, only not 

 more than 16 feet wide and 10 feet high, would answer admirably for Malmaison and 

 winter-flowering Carnations. In this instance the central staging would have to be 



