Greenhouse construction : a complete manual on the building, heating, ventilating and arrangement of greenhouses, and the construction of hotbeds, frames and plant pits . f lifters made of one inch by one-fourth band iron(B), about two feet in length, fastened rigidly to thelower edge of the ventilator (A), and extending downinto the house at right angles to it. A small wire cableruns the length of the house, and near each ventilator acord [C) is attached, which, after running through a 70 GKEENHOLvSE CONSTliUCTIOX. pulley, IS fastened to the lower end of the lifter. Thecable is arranged so th
Greenhouse construction : a complete manual on the building, heating, ventilating and arrangement of greenhouses, and the construction of hotbeds, frames and plant pits . f lifters made of one inch by one-fourth band iron(B), about two feet in length, fastened rigidly to thelower edge of the ventilator (A), and extending downinto the house at right angles to it. A small wire cableruns the length of the house, and near each ventilator acord [C) is attached, which, after running through a 70 GKEENHOLvSE CONSTliUCTIOX. pulley, IS fastened to the lower end of the lifter. Thecable is arranged so that it can be readily drawn throughthe house, lifting all of the sash to any required motive power may be applied to a small rope run-ning through pulley blocks, or by means of a smallwindlass. As first made, they were closed by their ownweight, and, as they were not held down in any way,accidents often happened in high winds. An improve-ment (Fig. 43 D) is in an additional rope, attached tothe bottom of each sash, and running through a pulleyto a point beyond, where it is fastened to the main the cable at the farther end of the house is carried. FIG. 43. A SIMPLE VENTILATING APPARATUS. over a pulley, and has a heavy weight attached to it, thecable will be drawn back, Avhcn it is desired to close theventilators, and will hold them securely in place. SHAFTING. In nearly all other ventilating machinery, tlie poweris conveyed by means of a gas pipe shaft running alongunder the ventilators. In some cases it passes tiirougha cross i)laced in the ridge post, about a foot from itsupper end, and in others, it is held in place by meansof a clamp fastened to the post. The usual method offastening is by moans of small hangers screwed to the SHAFTIXG. 71 rafters. When sashbars alone are used to form theframework of the roof, some method of hanging theshaft to the posts is desirable, but not necessary. Various methods of applying the power have beenmsed, the most common o
Size: 2268px × 1102px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, bookidgreenhouseco, bookyear1894
