596 



tion. The plan should secure the greates 

 light, economy of space and of heating, and directness 

 and simplicity in every operation. The simple sash-bar 

 frame, without rafters (Fig. 838) is the most satisfao- 



hot. Of i 

 cally, it 

 cost of n 



tory when properly constructed. The side walls should 

 be low and the roof comparatively flat. Usually there 

 is no glass on the side walls. Under most conditions, 

 the house should run north and south, particularly if 

 even in span (Fig. 8;!9), but the lay ..f tin- laud and the 

 location of existing features usual I v di t. iniiiM tlji- direc- 

 tion. If the he 



sloping land (Fig. 840), an uni.viii ..r l.n.ki 

 usually advisable. The widely different op 

 specting the merits and demerits of the diffei 

 are proof that each is good under certain circumstances. 

 It is the prevail 

 ing opinion that, 

 in broken spans, 

 the long roof 

 should be to the 

 south ; yet some 

 of the best newer 

 houses have the 

 short span — 

 whichis then very -,| 

 steep — facing the "^ 

 south (Fig. 843). 



In America, all 

 Forcing-h o u s e s 

 are heated by 

 means of small 

 wrought - iron 

 pipes, which fit 

 1 g et h e r with 



threads. The old-time cast-iron flues may be employed 

 for conservatories, but they are too bungling for Forc- 

 ing-houses. Thev do not admit of .sufBcient modification 

 in lay-out to adapt tliim tn tlie h>in; mid oftpn crooked 

 runsof Forciiii; li.iu .^ lai.li^hin. Ill -. Ill, ^^ r. m ^iit-iron 



aila|.t. .1 :. :,i 1,1.: and to higher temperatures. 



'IIm hi. ' I, I I ircing-house is probably in the 



pmiiurt.i.n nl i.iiimIiIi tn length as 1 is to 4 or 5. The 

 best housi-s are niri-ly less than 18 nr 20 ft. wide, and 

 rarely more than 30 to 35 ft. I'miu 4iMi I.. .liKI ft. is con- 

 sidered to be the greatest ]>ri>titali|i' IiiiL^th. Houses of 

 greater length are now building', but tlii'V nmst be con- 

 sidered an experiment. Parallel Ihhi.su.s are often 

 "nested" with good results,— the adjoining houses rest- 

 ing on a common wall. When the various houses are to 

 be used for one kind of crop, the partitions between 

 them may be omitted ; a very large space may then be 

 covered with practically one house without the necessity 

 of rearing a high roof. 



The accompanying illustrations (Figs. 838-843) show 

 various current styles of American Forcing-houses. For 

 further discussion of glass houses, see Greetilwiise. 

 L. H. B. 



The Winter Forcing of Vegetables.— The growing 

 of vegetables undei glass for the winter market has de- 

 veloped within the past ten years to 

 large proportions. It has grown from 

 the small compartment in private 

 houses devoted to 

 a small supply of 



lettuce and radishes to entire ranges of modern houses, 

 in which are grown almost the entire list of tender vege- 

 tables. The special crops, however, are usually confined 



pipes 

 has it 



are I 



Steam is less , a- 1 [-, m m-iall, ..ima ],-- ,ii,„ ,- ia.,|uired. 

 It also admits of Krcafcr vanatKin in flic luy-nut. Crooks 

 and obstacles are more easily overcome. In a large es- 

 etablishment, the place may be heated up sooner. Hot 

 water gives a milder heat because the pipes are less 



I four, the 

 lettuce. ra.li-li..-, i.anat.H 



The Fill. ■ I, 



pies rath, ■ ! ' ■ ,. ■ ;,■ 

 evervfbhia i,, -;,. ■/. :il, tl 

 kinds of veKftalilcs fore. 

 the same vegetable is gn 

 of widely different char 

 Skill in management an 

 the requirements ii, , , ;-: 

 tal elements, lim' ■ 

 The former is i..,,! 

 imperative when t : , 

 lettuce, rndisl,, i i, ! !, 

 vegetati\ ,■ nan , : :l 



light is ii-.i . , . ,,, 



841. Uneven span Forcine-house. 30 ft. wide. Hot 



of which is here discussed, — 

 nd cucumbers, 

 crop is a matter of princi- 

 nce local conditions have 

 iiethoils of culture and the 

 It fi.,,u,.iitlv happens that 

 with e.|,,i,l M.ia'css in soils 

 r li\ (liiT.iaiit cultivators, 

 iient ami ,],-,■ at t ,i,i i.i.i to details are 



ii,',i :,!■ 11, s.s. Two fundamen- 



V ■ tiiial: heat and light. 



,! I !-: the latter is almost 



I : , , ., I.; , ,1. With such crops as 



i, ! !, and asparagus, in which the 

 the plant is wanted, bright sun- 

 I iissary;lmtwithsuchcropsas 

 iinliers, melons and beans, in 

 , fruit isfheaim.noamountot heatwill 

 prove a substitute for sunlight in ripen- 

 ing the pollen, which is often the criti- 

 cal factor in the results. Therefore, a 

 situation where the maximum of sun- 

 shine may be had should be selected 

 if such crops are to he grown. 



The construction of the house is not 

 a matter of the first importance. The 

 three - quarter span house perhaps 



