IMPLEMENTS 



estimates of the piping needed. These figures 

 are based upon our own experience in structures 

 of ordinary proportions. For instance, the gen- 

 eral cross-section of one of the author's green- 

 houses in Arlington has dimensions frequent in 

 ordinary practice: Height at the back, 10 feet; 

 height at front, 4 feet; under the ridge, that is, at 

 the highest point of the interior, 15 feet; span, 

 33 feet. The length of this structure is nearly 

 400 feet. 



These figures, of course, indicate a definite 

 interior cubic content; and from the heating by 

 pipes actually done there I have derived rules 

 which admit of ready application, for all build- 

 ings substantially similar; even though somewhat 

 differing in height of front or rear wall, pitch of 

 roof, etc., and of any less or greater length, likely 

 to be erected for the purposes of the vegetable- 

 grower. 



A more elaborate calculation may generally be 

 had (free of charge to the person contemplating the 

 outlay), together with estimates for doing the work, 

 from any of the numerous establishments that 

 stand ready to contract for and supply modern 

 heating equipment in its various forms. In such 



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