GREENHOUSE 



694 



if they must be employed, special hot-water fittings 

 should be secured. 



In conservatories with high side walls, it is desirable 

 to place the flow pipes at the plate and the returns on 

 the wall or under the tables. Figs. 1001, 1002 and 1003 

 illustrate the lay ""t "£ pipfs £or water in a carnation, 

 rose and viulrt Immi . , 



Hot Wat,,- / . ' . /'• '" III "'!"■■ I:'i-.. Green- 



house.s the li.i' ■ ' ■■■•■" l.:l^'■l pi;- ■•.! under 



pressure by i'Im-im- lii.' i\ [1:111-1 "H i:iii1.- I''! |.i . \'i-ntany 

 dangerofthe iilowint; up ui lii. ■;,,;: 1 1 . 1 x valvL, 



with a weight set so as to alluw il ■•■ :;>•• In- 



fore the danger point is reachc I, 1 rt.iliM 



tank or expansion pipe. The >\ 1 - ni'Liily 



closed, the water as it warms is [•[■<•:■ •\ nni j pr.'^^ur. , 

 and steam cannot be formed. This nuikis it ],Msviiilc lo 

 raise the temperature of water in the C"il» ciuiir a imin- 

 ber of degrees higher than when an open tank i- iis,-.i. 

 As there is even more danger from an explosion of a 

 system when the water is under pressure than when 

 steam is used, care should be taken to see that the safety- 

 valve is in good working order, and that it is set at a 

 point well below the daiiKcr limit. 



Whe 



water is 1 

 of smaller 



GREENHOUSE 



3 where 50°, C0° and 70°, respectively, are required. 

 Fig. lOOi illustrates piping for steam in a rose house. 



Heating hy Fines. — Viheve fuel is cheap, and when 

 either a low temperature is desired in the house or the 

 outside temperature does not drop nnich below the 

 freezing point, hot-air flues may be used, but while the 

 cost of constructing them is not large, the dan^^er from 



fire is so great that they are not always ceo lical. A 



brick furnace is built at one end of the house, -.xuA from 

 this a 10- or 12-inch flue is constructed to etiiiy the 

 smoke and hot gases through the house to tlie chimney, 

 which may be at the farther end, or directly over the 

 furnace, the flue in the latter case making a complete 

 circuit of the house. When the houses are more than 

 (50 feet long, it is advisable to have a furnace at each 

 eiiil. and the Hue will then extend only to the center of 

 the liouse and return to the end from which it started. 

 Till first 30 feet of the flue should be of fire brick, but 

 lieyoiiil that it can be constructed of sewer pipe. While 

 either hard or soft coal may be used, the best results 

 will be secured with 3- or 4-foot lengths of hard wood. 

 Where the temperature does not drop more than II) or 12" 

 below zero, a temperature of 40° may be maintained in 



under all condi- 

 have the piping 

 weather, and th 



the 1 



reduction in the aniom : 1 



other hand, it is less . .-^ 



system, and requires raUn 1 ni..i 1 all. 

 system cannot be reconiuiemled f'jr 

 tions, and it will generally be best 

 adapted for all except the most ! 



to hi ' 



it III 



desir-, : I ..^ 



l',r ' ' -The arrangement of the 



heating |M]H I, r 11, r with steam need not be 

 unlike that tiliove described for hot water, 

 except that smaller How and return pipe; 

 are used. When there is but one or 

 two houses it is well to use over- 

 head flmv i.i]" ■. :is n rule only 



one I I -M a house. 



A i;-ii. ■ ■ ill be suf- 



ficirni 11 ,' ' ,>,,i.e feet of 

 radiuUuii, and L! ' ^ , :j-, 3K- and 

 4-inch supply pipes will an- 

 swer, respectively, for 700, 

 1,000, 1,400 and 1,900 square 

 feet of radiation. For long 

 houses it will be best to use 

 IK-inch pipe for the coils, but 

 1-inch pipe will answer for 



houses 100 feet or less in length. The coils should, of 

 course, run down hill, but if overheail supply pipes are 

 not used the connection may be nia^l.- af tin .ml of the 

 house nearest the boiler ami tin- i.tnin pipe may be 

 placed underneath the coil. In oi.p 1 to prevent the 

 water from backing up in the ooils it is desirable that 

 they should be at least 18 or 20 iuehes above the level of 

 the water in the boiler, while 3 or 4 feet would be even 

 better. There should be an automatic air valve at the 

 lower end of each coil, and, in order to regulate the 

 amount of steam, a shut-off valve should be placed in 

 both flow and return pipes. Unless there are several 

 coils in each house it will always be well to have valves 

 upon a number of the jiipes in the coils, so that all but 

 one or two ean I u( olT if .b-ire.!. To prrv.-nf tin- 

 water from liriirj- f'-r.-- .1 ..nl Ir-.m tin- I - -i 1 i-r win-n tln- 



valve in the rrlmn pipe iM-:ir iIm- In-.-ilrr. 



The amount oi r-Hlui i,,ii « lii.li will l.r n iinirnl tu se- 

 cure any desir.-d t.-inpn-ii m-i will var\ to M.ine extent 



with the amount ..r pr,- -.i,,v ili:,t is ,-arri.-.l in the boiler, 



but, as a rule, this is n,.i i ■.- tlnm liv.- poiunls. and often 



no pressure ;it all is ns, .1. It will oi-.limirily be best to 

 have the radiation sufficient to furnish the "temperature 

 desired in ordinarily cold weather without carrying any 

 pressure, and then by raising the pressure to from five 

 to ten pounds secure the heat that is needed during cold 

 waves. 



In determining the amount of radiation for a steam- 

 heated house, 1 square foot of pipe will answer for 9 

 square feet of glass, when 40° is desired, and for 7, Sand 



1002. Rose house, 150 x 20 ft., piped for water. 



a house 20 feet wide with one circuit of 12-ineIi sewer 

 pipe. Care should be taken that the flue in no iilacc is 

 in contact with woodwork, and that there is a ^'■radual 

 rise in the flue from the point where it leaves the fur- 

 nace to where it enters the chimney. ]_,. ij. Taft. 



Greenhouse Management. — Persons usually learn to 

 grow plants under glass by rule of thumb. Such knowl- 

 edge is always essential, but better and quicker results 

 are obtained if underlying truths or principles are 

 learneil :ii ih. mi. tii.i.-. Even if no better results in 

 plant-(-'r. - 1.- obtained, the learning of prin- 

 ciples I i I . - I .1 ii.irni.and it adds immensely to the 



intelli-.ii. 1 I : -I m the work. There is no Ameri- 

 .-aii will: :i\s to expound the principles of 



Gr.iiil... . - i lit. although there are excellent 



nninn.il . . :..lvi(^e for the growing of Various 



I'hiss. s -.1 I l,,,j . Ih.- best single recent American 



which brings together in i..lnni.- <-..ni-i-.- .hr. .-tions 



for the growing of the l.a.hiiL: kin.i- ..i iir..iiliouse 

 subjects. There are two kin.l- ..l pi m. i|.l.-- n. a]. pre- 

 bend in Greenhouse mantiir.iii. nt. -tl...-.- r.latini,' to 

 the management of the plants themselves, and those 

 dealing primarily with the management of the house. 



The first principle to be apprehended in the growing 

 of plants under glass is this : Each plant has its own 

 season of bloom. Every good gardener knows the times 

 and seasons of his plants as he knows his alphabet, 

 without knowing that he knows. Yet there are many 

 failures because of lack of this knowledge, particularly 



