118 GREENHOUSE CONSTRUCTION AND HEATING. 
to outside ; also corresponding tenons, 24in. long, on the 
ends of both the top and bottom rails, as shown in 
Fig. 75, taking care to cut the upper shoulders on the 
top rail 2in. longer, so as to fill up the rebates properly. 
The projecting ‘‘ horns” at each end of the styles should 
be rounded off neatly. Of course the mortises should be 
cut so as to allow of wedges being driven in top and bottom 
in the usual way. The joints are better made with thick 
white lead paint, or Stockholm tar, than with glue, and 
a #in. hole should be bored through each mortise and 
tenon (when putting the whole together), and a wooden 
pin be driven through tightly and cut off level on each side. 
Now at 103in. from the shoulders at each end of the 
top rail cut two mortises, Jin. wide and lin. long and deep, 
with another one midway between them, to receive similar 
tenons cut on the ends of three lengths of 2in. by lin. 
sash-bar. The bottom rail should be notched out lin. 
long and 4in. deep, in three places exactly opposite the 
mortises in top rail, the ends of the bars being cut to fit, 
leaving the head or ‘‘feather”’ (between the two rebates), 
Zin. or 3in. long, and tacking it down to the bottom rail 
with a couple of brads. Make all these joints with lead, 
like the others. The bars must, of course, be let into the 
bottom rail so that the rebates are flush with its upper 
surface. When the whole is fitted together and firmly 
pegged, procure a length of lin. by in. bar iron, 3ft. Qin. 
long, with holes for screws drilled at each end and opposite 
each bar, and when this is screwed on (on the under side) 
the light will be ready to be primed and glazed. One or 
two iron or brass handles should be screwed on to the 
top rail, of course. 
