268 
TEE FLORAL WORLD AND GARDEN GUIDE. 
yield its quota of return. This is referring to those cases where 
position makes it difficult to combine utility and beauty together ; 
but it does not bear on any instances where both can work har- 
moniously together, as is sometimes the case. As a rule, give the 
preference to the form that combines elegance and utility, where no 
other considerations crop up ; for although a house may be hand- 
some in appearance, and useful so far as its form is concerned, yet 
we have to take into account the probable cost of the working of 
such a form, according to the uses to which it is to be applied. For 
instance, no one would prefer a brick-pit to a span-roofed house for 
pine-growing, if they could maintain the proper temperature in the 
last-mentioned structure with the same outlay : but the latter would 
take nearly double the amount of firing to maintain the same tem- 
])crature as would a brick-pit; hence the preference for it. The 
same kind of reasoning will apply to the case of those who are 
engaged in growing large specimen plants for exhibition. The skil- 
ful cultivator of these things always gives the preference to a span- 
roofed house, on account of the more equal distribution of light to 
all parts of the plants, whereas a lean-to house always presents one 
dark side to the plants. Tnis, then, shows us that, although a 
certain amount of taste in arranging horticultural structures is 
desirable, utility of purpose and a becoming degree of economy in 
working them must be the paramount object sought. From my 
own experience, I know it is no trifling matter to decide in all cases 
which would be the best form to adopt. But, nevertheless, there 
are certain established forms of houses, adapted for different pur- 
poses, that it would not be desirable to alter if we could — such, for 
instance, as the lean-to form for early vineries, and the span-roofed 
form for ordinary plant-growing ; but still I would, when it was 
possible, substitute the latter for the former, especially for the fruit- 
house, the stove, and the orchid-house. But then, against the span- 
roof, for the two latter purposes, we must place the question of 
firing. Where this is a question of no moment, then I would advise 
by all means to build span-roofed houses, and I am satisfied that the 
result would be most satisfactory. The question of heating plane 
and fruit-houses is of great importance, now fuel is so expensive, 
and I prefer to deal with the most weighty matters first ; the addi- 
tional outlay for them in building at the outset is a point of com- 
paratively small importance, when we take into consideration the 
expense of maintaining the proper temperature. 
The advantages of span-roofed houses for all kinds of plant- 
growing are very considerable, although they are not so clearly 
made out upon paper as when put into practice. In addition to the 
more equal distribution of light over all parts of the house, there is 
a better means of securing a proper current of air; and when we 
consider how essential these two elements are to success in plant- 
growing, we have an indication of the superiority of the span over the 
other form ; and those who are aiming to achieve grand results would 
do well to study the comparative value of the two forms as adapted to 
their own case. Granting, then, that the span-roofed form is the most 
suitable for plant-growing, the next question that presents itself is the 
