82 
PARK AND CEMETERY. 
Greenhouses. — How to Build. VII. 
The ridge must be exactly midway between the 
gutter sills on the two sides of the house or between 
the gutter sill on one side and the wall plate or wall 
plate sill on the other, as the case may be. If the 
house is i8 ft. 8 inches inside, from sill to sill, the 
level or horizontal distance from the upper angle of 
the sill to the side of the ridge will be 9 ft. 4 3-8 
inches, the ridge being dressed to inches thick 
and the angle of the sill being i inches from its 
inner edge. If the rise is 6 inches to the foot the 
vertical height of the ridge above the sill angle will 
be 6-12 of this distance (9 ft. 4 3-8 inches) or 4 ft. 
8 3-16 inches. If the rise is 7 inches to the foot, 
the vertical height will be 7-1 2 of the horizontal 
distance. It should be noted that the height of the 
ridge is the height to the lower edge of the glass 
grooves in its sides. 
The end of the ridge is now to be brought 
firmly against the side of the shed, at the proper 
height and fastened by an iron or wooden bracket 
underneath. It is then brought to the proper posi- 
tion and braced and stayed throughout its length, 
temporarily, to keep it rigid until the bars are in 
place. Great care must be used to have it exactly 
the proper height and equidistant from the gutters. 
Any variations will cause the sash bars not to fit, 
and greatly add to the subsequent work. The gas 
pipe supports are then to be put in place, 6 of them 
in a 52 foot house which will bring them a little 
over 7 feet apart. 
Fig. 14 shows the gable end bars used at the 
north and south ends, i is the roof glass, 2 the ver- 
tical glass at the south end, not used, of course, at 
the north end, 6 the drip groove, which will face 
north on the bars at the south end and south on the 
north bars. (For Fig. 14 see last issue.) 
The end bars and intermediate bars will all be 
cut and mitered at the mill to make an exact fit. 
Figs. 7, 8 and 9 show the manner in which the 
lower ends of the bars (2) are joined to the sill or 
wall plate. The body of the bar butts square 
against the angle of the sill or plate and the tongue 
extends over and rests on the other bevel. A small 
nail is driven through the projecting tongue into the 
sill and a nail is “toed” in on each side through the 
body of the bar. The ridge joint is a simple miter 
joint. As soon as received from the mill and in- 
spected, and before priming, the bars should be 
stood on their lower ends in boiled oil about 6 in- 
ches deep to become thoroughly soaked, after 
which they are taken out dried and primed. 
Before the bars are set, the glass should be on the 
ground so that the bars can be spaced to fit, as dif- 
ferent lots of the same so-called size will vary a 
trifle. glass space, between adjacent sides of 
the tongues of the bars should be 1-16 inch more 
than the width of the glass and the bars should not 
be set until they have received the second coat of 
paint. A thick coat of paint applied after the bars 
are set will make the glass fit too tight. 
The ventilating sash will have been previously 
provided for. If a patent sash lifting apparatus 
can be afforded, and a good one is a great conven- 
ience, the sash will be narrow and form a continu- 
ous line along the ridge. If a double row is used, 
one on each side of the ridge, so much the better, 
but it requires two machines. Ordinarily in a 52 foot 
house about 3 ventilators would be used on each 
side of the ridge arranged alternately. These would 
extend 3 or 4 feet down the roof and would be just 
wide enough to cover two rows of glass and the 
tongues of their outside sash bars, requiring them 
to be about 2 inches wider than the actual width of 
the glass in the two rows. 
Ventilating sash are quite similar to ordinary 
window sash, except that there are no cross mun- 
tins and the lower rail is thinner than the upper, 
its surface being lapped by the glass so that the 
water flows down the sash and over the rail freely. 
The sash bar which would otherwise be under 
the centre of the ventilator is made shorter than 
the others and is attached to a header which is fitted 
in between the two bars on each side of it. 
Fig. 12 is a section across the header showing 
method of attaching the short bar, 12 is the header, 
6 the drip groove carrying the drip across to the 
long bars on each side. 3 is the lower end of the 
/ v[e n t i 1 a t o r 
resting on the 
header, 5 is 
the short sash 
bar carried 
onthe should- 
er projecting 
from the 
header, 4 the 
tongue of the 
bar and 6 the 
line of its drip groove, i is the glass resting on the 
shoulder of the bar and projecting into groove in 
the header. 
The sash lifter commonly used is a piece of strap 
iron about 3-16 by 3-4 or i inch and long enough 
to be easily reached when the sash is raised to its 
full height. At the upper end a hole is drilled and 
a staple passed through, the ends of which are rivet- 
ed firmly to a small iron plate, allowing the strap 
iron to swing loosely. The plate is bolted (screws 
invariably come loose) to the lower rail of the sash 
at the middle. Holes are drilled at intervals through 
the strap iron and a substantial iron peg is attached 
