QUA 
or it is a measure arising from the joint 
consideration of the quantity of matter, and 
the velocity of the motion of the body ; 
the motion of any whole being the sum or 
aggregate of the motion in all its several 
parts. Hence, in a body twice as great as 
another, moved with an equal velocity, the 
quantity of motion is double ; if the velo- 
city be double also, the quantity of motion 
will be quadruple. Hence the quantity of 
motion is the same with what we call the 
momentum or impetus of a moving body. 
Quantity, in grammar, an affection 
of a syllable, whereby its measure, or the 
time wherein it is pronounced, is ascertain- 
ed ; or that which determines the syllable 
to be long or short. Quantity is also the 
object of prosody, and distinguishes verse 
from prose ; and the economy and arrange- 
ment of quantities, that is, the distribution 
of long and short syllables, make what we 
call the number. 
The quantities are distinguished, among 
grammarians, by the characters short, as 
per; and-, long, as ros. There is also a 
common, variable, or dubious quantity ; 
that is, syllables that are one time taken 
for short ones, and at another time for long 
ones, as the first syllable in Atlas, patres, 
&c. Feet are made up of quantities. 
The quantity of syllables is known two 
ways. 1. By rules for that purpose. And, 
2. By authority. The rules for this end 
are taught by that part of grammar called 
prosody ; the authority made use of in this 
case is no more than examples from, or the 
testimony of, approved authors ; and is 
never used but either when the rules are 
deficient, or when we are unacquainted with 
them. 
QUANTUM meruit, is an action on the 
case, or a count in assumpsit grounded upon 
the promise of another, to pay him for doing 
any thing, so much as he should deserve or 
merit. 
QUANTUM valebant, in like manner is 
where goods and wares sold are delivered 
by a tradesman at no certain price, or to 
be paid for them as mijch as they are worth 
in general ; and the plantiff is to aver them 
to be worth so much. 
QUARANTINE, a trial which ships un- 
dergo when suspected of having on board 
persons infected with a pestilential disease. 
Physicians are occasionally consulted on 
this subject by government; who regulate 
this unpleasant restriction on the com- 
jnerce of the country by their judgment, as 
Jo the period of time within which the 
QUA 
effects of any infection received by any in- 
dividual on board, would be shown. 
The usual quarantine is forty days. This 
may be ordered by the king, with the ad- 
vice of the privy-council, at such times, and 
under such regulations, as he judges proper. 
Ships ordered on quarantine must repair to 
the place appointed, and must continue 
there during the time prescribed, without 
having any intercourse with the shore, ex- 
cept for necessary provisions, which are 
conveyed with every possible precaution. 
When the time is expired, and the goods 
opened and exposed to the air as directed, 
if there be no appearance of infection they 
are admitted to port. Ships infected with 
the pestilence must proceed to St. Helen’s 
Pool in the Scilly islands, and give notice 
of their situation to the Custom-house 
officers, and wait till the king’s pleasure 
be known. Persons giving false informa- 
tion to avoid performing quarantine, or re- 
fusing to go to the place appointed, or 
escaping ; also officers appointed to see 
quarantine performed, deserting their office, 
neglecting their duty, or givjng a false cer- 
tificate; suffer death as felons. Goods from 
Turkey, or the Levant, may not be landed 
without license from the king, or certificate 
that they have been landed and aired at 
some foreign port. 
QUARE impedit, in law, a writ which 
lies for him that has purchased a manor, 
with the advowson thereto belonging, 
against him that disturbs him in the right 
bf his advowson, by presenting a clerk when 
the church is void. 
QUARRY, a place under ground, out of 
which are got marble, free stone, slate, 
lime stone, or other matters proper for 
buildings. Quarries of free stone, are in 
many places opened, and the stone brought 
out in the following manner : they first dig 
a hole in the manner of a well, twelve or 
fourteen feet in diameter, and the rubbish 
drawn out with a windlass in large osier 
baskets, they heap up all around ; placing 
their wheel, which is to draw up their 
stones, upon it. As the hole advances, 
and their common ladder becomes too 
short, they apply a particular ladder for 
the purpose. When they have got through 
the earth, and are arrived at the first bank 
or stratum ; they begin to apply their wheel 
and baskets to discharge the stones as fast 
as they dig through them. In freeing the 
stone from the bed, they proceed thus: as 
common stones, at least the softer kinds, 
have two grains, a cleaving grain, running 
