CHAP. CIII. SALICA CER. PO’PULUS. 1663 
round-headed trees has been illustrated by Mr. John Thompson, in the first 
volume of the Gardener's Magazine ; of which paper the following is an abs- 
tract, with some explanatory additions :— The Lombardy poplar, considered 
as a tall conical mass of foliage, becomes of great importance in scenery, when 
contrasted with round-headed trees. It is a known rule in the composition 
of landscape, that all horizontal lines should be balanced and supported by 
perpendicular ones ; and, hence, the bridge in jig. 1521., displaying a long and 
1521 
conspicuous horizontal line, has its effect greatly increased by the poplars 
planted on each side of it. Not only the lines of the bridge are balanced 
and supported by the upright poplars, but lengthened and pleasing reflec- 
tions from the water are produced; which, breaking the horizontal gleams 
of light, not only produce variety and richness, but, by increasing the length 
of the perpendicular lines formed by the poplars, confer a degree of sublimity 
on the picture: since it is allowed by all writers on the material sublime, 
from Burke to Dugald Stewart, that gradually tapering objects of great height 
create the emotion of sublimity. This is admirably illustrated at Blenheim, 
where the poplar is an accompaniment to all the bridges, but more parti- 
cularly to that viaduct, near Woodstock, where the water first enters the park : 
this, seen from the neighbourhood of the great bridge, forms a landscape of 
much beauty and purity. On the other hand, the planting of the island in the 
lake at Blenheim is as much at variance with good taste as the planting at 
the bridge is conformable to it. It is covered with tall poplars, forming a mass 
which seems too big for its base; and which, from its stiff and upright form, 
is too strongly opposed to the varied outline of the surrounding wood and 
water, and destroys all breadth of effect. How much more agreeable it would 
have been, to have looked down from the bridge on an island varied with 
small groups of well-selected, low, round-headed trees !_ Lombardy poplars 
may be advantageously planted wherever there is a continuance of horizontal 
lines ; but they should be so arranged as to form a part of those lines, and to 
seem to grow out of them, rather than to break or oppose them in too abrupt 
amanner. In the case of a stable or other agricultural building, where the 
principal mass extends in length, rather than in height, it would be wrong to 
lant Lombardy poplars, or other tall fastigiate trees, immediately before the 
uilding ; but they will have a good effect when placed at the sides, or behind 
it, as shown in fig. 1522. This poplar is very generally planted in front of 
the suburban cottages and residences which are to be found within a few 
5Q 
