58 GREENHOUSE CONSTRUCTION AND HEATING. 
of each square of glass may, of course, be projected beyond 
the plate far enough to allow of the drip falling in to the 
gutter ; but when this is done the glass appears to be peculiarly 
liable to breakage, and unless each square sits down very 
closely on the plate, a good deal of air 
will find an entrance at this point. 
In some cases, a strip of zinc, about 
4in. wide, is tacked along the outer face 
of the plate, overhanging sufficiently to 
allow of all the drip falling into the 
gutter. The glass is brought down as far 
Fig. 44. as the edge of the plate, and, of course, 
overlaps the zinc an inch or two. Copper nails should be 
used to fasten the zine in place. 
Yet another way, and one much favoured by the growers 
in the Worthing district, is to tack on to the outside of the 
plate a diamond-shaped fillet or bead, as in Fig. 44. This 
supports the lower edge of the glass, and conducts 
the water into the gutter. 
But decidedly the best method of all, in my 
opinion, is the adoption of a wooden ‘‘drip,” 
consisting of a board, 44in. to 6in. wide, and in. 
or #in. thick, fixed as shown in Fig. 48. 
If fixed as at a, with the upper edge flush with 
the ridge on the plate, the ends of the bars 
can be just sawn to shape, but if carried up 
higher, as at B, the ends of the bars must be 
chiselled out. This affords perfect support to the glass, and 
makes a very neat and tight job. By nailing a 24in. by 3in. 
batten (planed) on to the lower edge of the drip-board (as at 
B in Fig. 43) at right angles, and giving the whole a good 
Fia. 45. 
