u 
a year, to solve the phenomena arising from 
the annua] motion, and every twenty-four 
hours, to account for Arose of the diurnal 
motion. 
TYGER. See Felis. 
TYLE, or Tile, in building, a sort of 
thin, fictitious, laminated brick, used on the 
roofs of houses ; or more properly a kind of 
fat clayey earth, kneaded and moulded, of 
a just thickness, dried and burnt in a kiln 
like a brick, and used in the covering and 
paving of houses. See Brick. 
There are various kinds of tyles, for the 
various occasions of building ; as plain, 
thack, ridge, roof, crease, gutter, pan, 
crooked, Flemish, corner, hip, dormar, scal- 
lop, astragal, traverse, paving, and Dutch 
tyles. 
Flemish or Dutch tyles are of two kinds ; 
ancient and modern. The ancient were 
used for chimney foot-paces : they were 
painted with antique figures, and frequently 
with postures of soldiers ; some with com- 
partments, and sometimes with moresque 
devices ; but they come much short of the 
design and colours of the modern ones. 
The modern Flemish tyles are commonly 
used plastered up in the Jaumbs of chimnies, 
instead of chimney-corner stones. These 
are better glazed, and such as are painted 
(for some are only white) are done with 
more curious figures, and more lively co- 
lours, than the ancient ones. But both 
kinds seem to be made, of the same whitish 
clay as our white glazed earthen ware ; the 
modern ones are commonly painted with 
birds, flowers, &c. The ancient ones are 
only five inches and a quarter square, and 
about three-quarters of an inch thick ; the 
modern ones six inches and a half square, 
and three-quarters of an inch thick. 
TYMPAN, or Tympanum, in architec- 
ture, the area of a pediment, being that 
part which is on a level witli the naked of 
the frieze. Or it is the space included be- 
ll 
tween the three coinishes of a triangular 
pediment, or the two Cornishes of a circular 
one. Sometimes the tyrapan is cut out, 
and the part filled with an iron lattice to 
give light, and sometimes it is enriched with 
sculpture in basso relievo. 
Tympan, among printers, a double frame 
belonging to the press, covered with parch- 
ment, on which the blank sheets are laid 
in order to be printed off. See Printing. 
tympanum, or Tympan, in mecha- 
nics, a kind of wheel placed round an axis, 
or cylindrical beam, on the top of which 
are two levers or fixed staves, for the more 
easy turning the axis, in order to raise a 
weight required. The tympanum is much 
the same with the peritrochium, but that 
the cylinder of the axis of the peritrochium 
is much shorter, and less than the cylinder 
of the tympanum. 
Tympanum o/* cl lyKtchine, is also used 
for a hollow wheel, wherein one or more 
people, or other animals, walk to turn 
it; such as that of some cranes, calen- 
ders, &c. 
TYPE, a copy, image, or resemblance of 
some model. This word is much used 
among divines, to signify a symbol, sign, or 
figure of something to come ; in which sense 
it is commonly used with relation to anti- 
type, which is the thing itself, whereof the 
other is a type or figure. 
TYPHA, in botany, a genus of the Mo- 
noecia Triandria class and order. Natural 
order of Calamariae. Typh®, Jussieu. Es- 
sential character : male, ament cylindrical ; 
calyx indistinct, three-leaved ; corolla none : 
female, ament cylindrical, below the males ; 
calyx a villose hair; corolla none; seed 
one, placed on a capillary down. There 
are two species, viz, T. latifolia, great cat’s- 
tail, or reed mace ; and T. angustifolia, nar- 
row-leaved cat’s-tail. 
TYPOGRAPHY, the art of printing. 
See Printing and Stereotype. 
u. 
U Or u, the twentieth letter, and fifth 
} vowel of our alphabet, is formed in 
the voice by a round configuration of the 
lips, and a greater extrusion of the under 
one than in forming the tetter o, and the 
tongue is also more cannulated. The sound 
is short in crttst, must, tun, tub-, but is 
lengthened by a final e, as in tune, tube, &c. 
In some words it is rather acute than long ; 
as in brute, flute, lute. Sec. It is mostly long 
in polysyllables ; as in union, curious, &c. 
but in some words it is obscure, as in na- 
ture, venture, &c. This letter, in the form 
V, or V, is properly a consonaiit, and as 
