ARCHITECTURE. 
we dosed at the top, the apertures being 
always wide, are generally made with arched 
heads : the usual proportion of the arcade 
is that which has its height double to its 
breadth, or a trifle more. 
The usual ornaments of gates are rustics 
of several kinds, such as columns, pilasters, 
entablatures, pediments, attics, blocking 
courses, imposts, archivolts, consoles, 
masks, niches, &c. In gates which are 
not closed at the top, the breadth of the 
piers may be from two-fifths to a quarter of 
their height, reckoning from the bottom of 
the plinth to the top of the cornice. 
The rustics may either be plain, frosted, 
or vermicuiated. The smallest width that 
can be given to the aperture of a gate is 
nine feet, which is but just sufficient for the 
free passage of coaches-; but if waggons 
and loaded carts are to pass, it must not 
be less than ten or eleven feet, and if the 
gate is for the entrance of a city, it should 
not be of a less width than eighteen or 
twenty feet. The composition of gates 
should be characteristic of the place to 
which they are to open. Gates of cities 
and fortresses should have the appearance 
of strength and majesty : their parts should 
be large, few in number, and of bold re- 
lief. The same ought likewise to be ob- 
served in the gates of parks, public walks, 
or gardens; these succeed better when 
composed of rustic work, and of the mas- 
sive orders, than when they are enriched 
with nice ornaments or delicate profiles. 
However, triumphal arches, entrances to 
palaces, to magnificent villas, town or 
country houses, might with propriety be 
composed of the more delicate orders, and 
be adorned in the highest degree. 
The gates of parks and gardens are com- 
monly shut with iron folding grates, either 
plain or adorned : those of palaces should 
likewise be so, or else be left open all the 
day. 
Niches. A niche, is a recess in a wall, for 
the purpose of enshrining a statue or some 
other ornament, or as an ornament to the 
wall itself. Among the works of the Ro- 
mans, niches have either that of a circular 
or rectangular plan: the heads of those 
which have circular plans are almost always 
spherical. In the middle of the attic of tire 
piazza of Nerva, at Rome, there is a niche, 
with a rectangular elevation, and a cylindri- 
cal back and head : those upon elliptic 
plans were not much used by the ancients. 
In Wood’s Ruins of Palmyra, there are, 
however, two exhibited with elliptic heads, 
within the entrance portico of the temple 
of the Sun ; but no plan is shewn. Niches, 
upon rectangular plans, have most frequent- 
ly horizontal heads : there are a few to be 
found with cylindrical heads : those upon 
circular and rectangular plans are, for the 
most part, placed alternately, for the sake 
of variety. The plans of niches with cy- 
lindrical backs should be semicircular, when 
the thickness of walls will admit of it ; and 
the depth of those upon rectangular plans 
should be the half of their breadth, or as 
deep as may be necessary, for the statues 
they are to contain : their heights depend 
upon the character of the statues, or on 
the general forms of groups introduced ; 
seldom exceeding twice and a half ot their 
width, nor less than twice. Niches for 
busts shouldhave nearly the same proportion 
with regard to one another ; their heights, in 
some cases, may be something more than 
their breadth. Some niches may be formed 
with cylindrical backs and spherical heads : 
some of them may be entirely formed with 
hemispherical backs ; others of spheroidal 
backs, with the transverse or conjugate axis 
of the ellipsis vertical, as may be most suita- 
ble to the character of the thing to be en- 
shrined : those with spheroidal backs may 
have their horizontal sections all circles of 
different diameters, and, consequently, then- 
sections through the vertical axes, all equal 
semi-ellipses, similar to each other ; or all 
their horizontal sections may be similar el- 
lipses, and the sections through the vertical 
axis of the niche will be dissimilar ellipses 
of equal heights, at least for one half of the 
niche ; but spheroidal niches with such sec- 
tions are difficult to execute, and not so 
agreeable to the eye as those with circular 
horizontal sections. Niches for busts may 
be of any of these last forms, or of any 
other form used by the ancients. 
Niches are susceptible of the same de- 
corations as windows; and whether their 
heads be horizontal, cylindrical, or spheri- 
cal, the inclosure may be rectangular. In 
the ruined edifices of antiquity, tabernacles 
are a very frequent ornament, and these 
often disposed with triangular and arched 
pediments alternately : the character of the 
architecture should be the same as that 
which is to be placed in the same range 
with them. Niches are sometimes disposed 
between columns and pilasters, and some- 
times ranged alternately in the same levels 
with windows: in either case they should 
be ornamented or plain, as the space will 
admit. 
