60 GREENHOUSE CONSTRUCTION AND HEATING. 
must, of course, be filled with putty before putting the 
glass in, may be dispensed with by tacking a short length of 
beading, or fillet, in between the bars, to support the upper 
edge of the squares, these being well bedded in putty, 
trimmed off and 
=. painted ; but this plan 
= =" is only a makeshift. 
Bal Eee ae The lengths of 
Pere aS ee ore ee 
¢ + yridging are joined to- 
Fia. 46. gether by  scarfing 
the ends, as shown in the accompanying sketch (Fig. 46). 
In this, a is a wooden wedge, driven in to tighten up the 
joint, and cut off flush on each side afterwards ; a couple of 
long nails or screws at B and c make the joint complete. 
Such a joint in a Tin. plank should be 16in. to 18in. long. 
Capping.—This is a length of wood worked to the 
sectional form shown in Fig. 47, and fixed on the top of 
the ridge-plank, as shown. Its use is partly to protect the 
ridge from the weather and partly to prevent any drip 
from entering along either side of the ridge, or along the. 
top of the ventilators. When these are hung 
directly to the ridge, the capping is quite 
effectual for this purpose, but where a hanging 
Piece is employed the joint comes just outside 
the capping, and in such cases it should be 
covered with a strip of thin canvas or stout 
calico, well tacked down top and bottom, and painted two. 
coats. 
, Purline,—This is a stout horizontal bar, or piece of 
quartering, fixed along crosswise of the rafters and about. 
hali-way between the ridge and wall or eave-plates. 
