30 THE CONSTRUCTION OF THE FORCING-HOUSE. 



sider the draining of the water into the groove to be the 

 very thing to be avoided, for it is then discharged at the 

 bottom of the bar into the joint with the plate, and hastens 

 decay in one of the very weakest points in the frame. I now 

 use entirely a perfectly plain sash-bar, which is " run " from 

 white pine at the home mill. Its form is shown in Fig. 18 

 (page 35). For ordinary roofs, and glass not more than 12 

 inches wide, these bars may be i x i} or itf x i# inches in 

 body measure. The illustration shows a cross-section of a 

 heavy bar, at one-half natural size. In lots of 1,000 lineal 

 feet, this bar costs us the price of the lumber plus $4 for 

 "running." If the grooves were added, the cost of "run- 

 ning" would be about $6. In large quantities, these prices 

 could be much reduced. In very wide roofs of little slope, 

 and especially when very large glass (18 to 20 inches wide) 

 is used, a bar 2x3 inches is safest and best. Such bars will 

 hold a man's weight. If the house is properly glazed, 

 there will be no "drip" of consequence. 



The plate. Perhaps the shortest lived part of the frame 

 of the ordinary glass house is the plate at the eaves. Much 

 of the condensation upon the glass finds its way to the plate, 

 and if the glass is butted, all the condensation strikes it 

 which does not fall in "drip." In the very wide shed roof or 

 broken-roof houses, the front plate (upon the lower wall) 

 receives nearly all the roof drainage, and this is the one, 

 therefore, to be chiefly protected. The plate, therefore, 

 soon decays unless the greatest care is taken to give it a 

 bold slant, and to keep it well painted. Fig. 19 (page 36) 

 shows an excellent plate, half-size, cut from a pine or cy- 

 press stick. A plate with half the slope of the side A B will 

 still hold the water in globules and miniature pools, partic- 

 ularly after the paint has begun to blister. In order to 

 prevent the water from following back on the plate and 

 keeping the wall wet, a groove like that at a, a, in Figs. 

 20 and 25 (pages 37 and 39), is useful. A similar one on 

 the outside of the plate will keep the rain from following 

 down the wall. If the drip from the inner edge of the plate 



