THE WOODWORK. 67 
ventilators so tightly that they cannot ‘‘sit down” easily 
and well, or so that they ‘‘gape” at the bottom when 
closed. In fact, great care ought always to be bestowed on 
the proper hanging of ventilators, as unless they fit closely 
at all points, there will be a considerable loss of heat in 
windy weather, to say nothing of the inconvenience and 
damage caused by drip. 
Before proceeding to consider the ventilator seats, 
another point of some importance must be dealt with. 
This is whether the bars should be carried through to the 
ridge beneath the ventilators or not (see a and B, Fig. 54). 
The latter plan has the neater 
S655 > and better appearance, and in this 
Zs case the ventilator seat can be put 
in in one piece, and a close fit is 
thus more easily made between 
Fig. 55. the two. If this method is adopted, 
a tenon should be cut on the end of each short bar (see Fig. 
55), to fit into a corresponding mortice in the seat. The 
seat should be made of fairly stout stuff, 13in. or 2in. thick, 
and rebated or grooved on the lower side to take the upper 
F 2 
