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GREENHOUSE 



GREENHOUSE 



amongst the earliest attempts to make low glass ranges 

 for plants, particularly in England. 



It was about the beginning of the nineteenth century 

 that great improvements began to be made in the glass- 

 house. This new interest was due to the introduction 

 of new plants from strange countries, the improvement 

 of heating apparatus, and the general advance in the 

 art of building. The ideals which prevailed at the open- 

 ing o the century may be gleaned from J. Loudon's 

 "Treatise on Several Improvements recently made in 

 Hot-Houses," London, 1805. One of the devices recom- 

 mended by Loudon will interest the reader. It is shown 



Location, Plans, Grading, Foundations, Framework 

 Glazing and Painting, Plant Tables, Ventilation, Heat'- 

 ing. 



Location. Greenhouses which are intended for use 

 in connection with the garden should be placed, for con- 

 venient attendance, within the garden inclosure or 

 along its boundary. A good location for the garden 

 will usually be found the best one for the Greenhouse. 



A conservatory or Greenhouse designed for a private 

 place, where specimen and blooming plants will be kept 

 for the pleasure of the family and entertainment of 

 visitors, should be attached to the dwelling or located as 



987. Switzer's glasshouse, built on an inclined wall. 1731. 



in Fig. 988. The bellows is used for the purpose of 

 forcing air into the house, that the plants may be sup- 

 plied with a fresh or non-vitiated atmosphere. "By 

 forcing the air into the house, once a day or so, double 

 the quantity of air which the house usually contains" 

 can be secured. The house could be "charged. " The 

 tube leading from the bellows is shown at &; it dis- 

 charges at c. Curtains run on the wire, i; the curtain 

 cord is at f. 



All commercial structures are now built on the 

 plan of the long, low glass range, with very little height 

 at the eaves. The taller glass structures, if built at all, 

 are used for conservatory purposes or as architectural 

 features. The general tendency of the building of glass 

 structures is towards extreme simplicity (Fig. 1005). 

 In the extreme South, lattice-work buildings are some- 

 times used for the protection of plants, both from light 

 frosts and from the sun (Fig. 989). The heating which 

 is now employed in this country is of three different 

 kinds: hot water under very low pressure or in the open 

 tank system; hot water in practically closed circuits; 

 and steam. Hot water under low pressure is an old-time 

 idea of heating, and is not now popular in this coun- 

 try except for conservatories and private establish- 

 ments. The heavy, cumbersome pipes are not adapted 

 to laying over long distances and under varying con- 

 ditions. The commercial houses are now heated by 

 means of wrought-iron pipes, which go together with 

 threads. The comparative merits of steam and hot 

 water in these wrought-iron pipes are much discussed. 

 For large establishments, particularly those which are 

 on various elevations, and which are likely to be changed 

 frequently, steam is preferable; and, on the whole, it 

 seems to be gaining in favor for commercial establish- 

 ments. It requires no more attention on the part of the 

 operator, when modern heaters are used, than hot water. 

 However, the merits of one system or the other are 

 very largely those of the individual establishment and 

 apparatus, and the personal choice of the operator (see 

 Forcing). 



The special American literature on Greenhouse con- 

 struction and management will be found in the follow- 

 ing books: Leuchars'" Hot-Houses, "1850; Henderson's 

 "Practical Floriculture," first ed., 1869; Field's "Green- 

 house as a Winter Garden," 1869; Hunt's "How to 

 Grow Cut-Flowers , " 1893 ; Taf t' s Greenh ou se Con struc- 

 tion," 1893; Bailey's "Forcing Book," 1897; Taft's 

 "Greenhouse Management," 1898. L H B 



Greenhouse Construction. - For convenience, this sub- 

 ject may be considered under the following heads: i.e., 



near as possible in a well-kept part of the grounds. A 

 conservatory does not require a full southern exposure. 

 Most decorative plants thrive as well or better and con- 

 tinue in bloom for a longer time if kept in a house hav- 

 ing plenty of light, but so located as to receive but lit- 

 tle direct sunlight. Large ranges of glass adapted to a 

 variety of purposes are generally kept separate from 

 other buildings. In parks the location should be near a 

 main entrance.- 



The location of a range of glass for commercial pur- 

 poses, where the elements of expense and profit are to 

 have the first consideration, is of great importance. 

 The chief items which determine the desirability of a 

 suitable location are the adaptability and value of the 

 land, cost of fuel delivered, ample and inexpensive 

 water supply, and proximity to a market. The top of a 

 bleak hill or the bottom of a valley should both be 

 avoided. Level land, or that having a southerly slope, is 

 the best. 



Plans. When a site for the proposed Greenhouse had 

 been decided upon, full plans should be made before 

 commencing to build. The plans should embrace not 

 only the glass, which is required at once, but should 

 provide for the largest increase which can be antici- 

 pated. In this way houses can 

 be erected which are convenient 

 to work and have a good ap- 

 pearance, with small extra cost 

 for building only part at a time. 

 Attention should be given to 

 the special peculiarities of the 

 location, like the exposure to 

 the sun, grade of ground, shape 

 of lot, and best location for the 

 heating apparatus. Each com- 

 partment should have the pro- 

 per form of house and exposure 





Loudon's device for charging a Greenhouse with air. 



