greenhouse growers are convinced that better returns can be received from houses 

 of a wider span than from the old fashioned narrow ones. In houses having a 

 wider span, and of necessity higher eaves, the volume of air is increased, the 

 glass surface is proportionately iiicreased, and the working cost of the greenhouse 

 is lessened. The volume of air is increased due to the increased length of the 

 sash bars and the increased height of the eaves, and this is what greenhouse men 

 require for successful growing — more air. It is an experiment no longer, but an 

 actual cultural necessity, to have plenty of air over the plants. The plants grow 

 better in every stage, and are not so liable to suffer so much from the sudden 

 lowering of temperature. With the increased length of sashbar, etc., the glass sur- 

 face is increased, and this admits more light and also makes adequate ventilation 

 easy. 



With the higher eaves the ventilating apparatus can be easily placed and 

 operated, taking up practically no room in the house. The working cost or crop 

 costs are several per cent, cheaper in wide houses than in the old narrow ones, 

 because the houses have higher eaves, and cultural operations can be carried on 

 close up to the sides without fear of bumping into the sash bars, etc., as is common 

 on going into the narrower houses. 



Widths of houses are arbitrary to the builder. The prevailing width of 

 house being built at the present time in the United States seems to be seventy-five 

 feet. Many plants have passed from the twenty foot width to the twenty-five 



Seventy-five foot houses are preferred by the majority of large growers. The doors in 

 this 75 X 460 ft. house admit all cultivating machinery. 



foot and then to the forty foot, and experienced men seem to agree that the seventy- 

 live foot house gives them as nearly a perfect house as tliey can get. The forty 

 foot house has been built extensively by many vegetable growers, and gives entire 

 satisfaction; but as soon as the seventy-five foot house has been operated a season 

 95 per cent, of the growers ^vill have no others. 



The increased facilities of handling materials,, supplies and soil cut down the 

 cost of production in the wider houses at a greater rate than in the narrower houses. 

 Conditions alter cases. For this reason the man who is starting a small plant could 



