GARDEN ARCHITECTURK 
237 
ridge- and- furrow of a roof, without laps, thereby effectually obviating any leakage 
from the outside) is not employed, the amount of drip in the interior, when the 
laps are not puttied, or the putty is decayed, will be very considerably less than 
where the water has to run down a long slope of glass. Finally, by the employ- 
ment of the glass just mentioned in a ridge-and-furrow roof, the house can be made 
quite air-tight ; there will be a less escape of heat ; the effects of severe cold 
winds will scarcely be experienced by the plants v/ithin ; no natural agents, save 
extraordinary storms of hail, (and these will lose much of their power by the 
greater strength of a single piece of glass, and the obliquity of its surface,) can 
ever break the glass ; the wood-work will not be shaken and cracked by shifting, 
and no kinds of apertures will be left, so that wet could be admitted and decay 
produced ; nor will accidents occur through the unequal expansion of the lights 
in wet weather, which so often prevents them from sliding properly in flat-roofed 
houses, or from any other cause than mere carelessness. 
We have entered thus partially into the merits of ridge-and-furrow roofs, 
because it must appear, from a due reflection on the circumstances alluded to, on 
others which every gardener will be able to see and appreciate, and on the really 
small extra sum which requires to be expended on them, that they are not the 
expensive and extravagant objects which some would represent them. It remains 
to state, that they are not suitable for houses of limited dimensions, or those which 
are not sufficiently long to admit of their being made of a considerable breadth 
without disproportion. A small structure ought to be quite plain in its outlines, 
that it may appear as large as possible ; while it may be asserted as an equally 
fundamental rule, that a spacious conservatory should have variety in its roof, in 
order to avoid that monotony and massiveness which would otherwise be conspi- 
cuous. For a common span-roofed house, therefore, of moderate size, a plain 
sloping roof will be most appropriate. A larger building will be most aptly 
covered by a roof with a simple curve. And an edifice on a further enlarged scale 
may be most agreeably roofed by the combination of the curved and ridge-and- 
furrow plan. 
Of the comparative suitability of iron and wood for the roofs of plant-houses, 
we shall not at present stop to inquire. Where the contour of the whole is circular, 
or of any figure inclining thereto, the different divisions being ranged round a 
central area, iron will be the fittest and most convenient material for enabling the 
builder easily and elegantly to lessen the distance between the bars at the top, and 
augment it towards the bottom. For every other figure, the two may be indif- 
ferently selected, as the taste, experience, or prejudices of the operator may dictate. 
Circular buildings are so exceedingly attractive to the eye, and the accommo- 
dation they afford to the various plants, of peculiar habits, that come within the 
denomination of ornamental exotics, is so admirably congenial, that we are sur- 
prised not to have witnessed their adoption more frequently than we have yet done. 
Duly relieved by some architectural pile in the middle, they would constitute one 
VOL. VIII. NO. XCV. L L 
