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Chambers, Ephraim, 1680 (ca.)-1740 / Cyclopædia, or, An universal dictionary of arts and sciences : containing the definitions of the terms, and accounts of the things signify'd thereby, in the several arts, both liberal and mechanical, and the several sciences, human and divine : the figures, kinds, properties, productions, preparations, and uses, of things natural and artificial : the rise, progress, and state of things ecclesiastical, civil, military, and commercial : with the several systems, sects, opinions, &c : among philosophers, divines, mathematicians, physicians, antiquaries, criticks, &c : the whole intended as a course of antient and modern learning

Burnishing - Bylaws,   pp. 135-137 PDF (3.1 MB)

Page 135

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cording to Schottus, burnt Pieces of Wood, at the Diflance
of 15 or r6 Paces.
M.   (f'cbirnhaus's Mirror, at leaft, equals the former,
both in Bignefs and Effe&: The following Things are no-
ted of it in the -ACa Eruditorum.   r. Green Wood
takes fire ir.flantaneoufly, fo as a firong Wind can't extin-
guifh it. 2. Water boils immediately, and Eggs in it are
prefently edible. 3. A Mixture of Tin and Lead, three In-
ches thick, drops prefently: An Iron or Steel Plate becomes
red-hot prefently,and a little after burns into Holes. 4. Things
not capable of melting, as Stones, Bricks, ec. become foon
red-hot, like Iron.  5. Slate becomes firfl white, then a
black Glafs. 6. Tiles are converted into a yellow Glafs,
and Shells into a blackifh yellow one. 7. A Pumice Stone
emitted from a Volcano, melts into a white Glafs: And, 8.
A piece of a Crucible alfo vitrifies in eight Minutes. 9.
Bones are foon turn'd into an opake Glafs, and Earth into a
black one. The Breadth of this Mirror is near three Leip-
fick Ells, its Focus two Ells diflant from it : It is made of
Copper, and its Subflance is not above double the Thick-
ne~s of the Back of a Knife.
Villette, a French Artifi of Lyons, made a large Mirror,
bought by ltavernier, and presented to the King of Per-
fia  a fecond, bought by the King of Denmark; a third
prefented by the French King to the Royal Academy;
a fourth has been in England, where it was publickly ex-
pos'd. The Effeffs hereof, as found by Dr. Harris and
Dr. DDefaguliers, are, that a Silver Sixpence is melted in
7" and  ; a King George's Halfpenny in z6", and runs
with a Hole in 34. Tin melts in 3', CaP Iron in I6l', Slate
in 3"; a foflile Shilling calcines in 7"; a piece of Pompey's
Pillar at Alexandria, vitrifies in the black Part in so", in
the white in 54; Copper Ore in 8": Bone calcines in 4",
vitrifies in 3 3. An Emerald melts into a Subflance like a
Turquois Stone; a Diamond weighing 4 Gr. lofes . of its
Weight: The Asbeflos vitrifies; as all other Bodies will
do, if kept long enough in the Focus: When once vitri-
fy'd, the Mirror can go no further with them. This Mir-
ror is 47 Inches wide; and is ground to a Sphere of 76
Inches Radius: fo that its Focus is about 38 Inches from
the Vertex. Its Subfilance is a Compofition of Tin, Cop-
per, and Tin-Glafs.
Every Lens, whether Convex, Plano Convex, or Con-
vexo Convex, colleas the Sun's Rays, difpers'd o'er its
Convexity, into a Point, by Refraffion; and is therefore a
fBAurning Glafi. The moil confiderable of this kind known,
is that made by M. de 7Ijchirnhaufen : The Diameters of
renfes are three and four Feet; the Focus at the Dif-
of Iz Feet, and its Diameter an Inch and half  To
ce the Focus the more vivid, 'tis colfecled a fecond time
a fecond Lens parallel to the firfe; and plac'd in that
where the Jiameter of the Cone of Rays form'd by
fir&c Lens, is equal to the Diameter of the fecond: So
it receives 'em all; and the Focus from  an Inch and
if, is contracted into the Space of eight Lines, and its
e increas'd proportionably. Its Effies, among others,
elated in the AC/a .Erudit. LiPrii, are, That it lights
Wood, even moiflen'd with Water, into a Flame, in-
Jly; -that Water, in a little Veltel, begins to boil pre-
.y; all Metals are melted; Brick, Pumice Stone,
Ilht Wares, and the Asbeflos Stone, are turn'd into Glafs;
hur, Pitch, Lfc. melted under. Water: The Amhes of
etables, Woods, and other Matters, tranfmuted into
s. In a word, every thing apply'd to its Focus, is ei-
melted, tumn'd into Calx, or into Smoak; and the
ours of Jewels, and all other Bodies, Metals alone ex-
edare chang'd by it. He obferves, that it fucceeds
t when the Matter apply'd is laid on a hard Coal well
ho the Force of the Solar Rays be here found fo flupen-
;I7 yet the Rays of the Full Moon, colleqed by the fame
wning Glafs, don't exhibit the leat Increafe of Heat.
arther, as the Effets of a . Burning Lens depend whol-
n its Convexity, Atis no wonder that even thofe pre-
I of Ice produce Fire, Wc. A Lens of that kind is ea-
prepar'd, by putting a piece of Ice into a Skuttle, or
w Segment of a Sphere, and melting it over the Fire,
it accommodate it felf to the Figure thereof.
For will thofe ignorant of Dioptrics, be lefs furpriz'd to
Flame, and the Efe&fs thereof, produced by means
he RefraEtion of Light in a Glafs Bubble fiMlNd with
er. See LENS.
rAfus tells us, that an Artift of Drefden made burn-
M/.oirrors of Wood, biger than thofe of M. I(fchirn-
t or Villete, which had  eiffes at leaft equal. to any of
. 'raberus teaches how to make burning Mirrors of
f Gold,* viz. by turning a Concave, laying its Infide
aly with Pitch, and covering that with fquare Pieces of
Gold, two or three Fipgers.broad, falifening 'em on, if
dIbe, by Fire. He adds, that very large Mirrors may
made, of 30, 40, or more Concave Pleces, artfully
'd in 1 Er'd wooden Dil or Skuttle X the E jffts of
which will hof be much lefs, than if the Surface was Eobi:
Zahnius adds, further, that Newman, an Engineer at
Vienna, in 1699, made a Mirror of Pafiboard, cover'd with-
in fide with Straw glu'd to it; by which all kind of Metals;
Fic. were melted. See MIRROR.
BURNING of Land, call'd alfo vulgarly Denjbiring, quafi
DevonJhiring, or fDenbyjhiring, as being moft ufed there:
A Method of preparing and fertilizing Lands barren, four,
heathy and rufiy, for Corn; by paring of the Turf, and
drying, and burning iton the Ground. The fame Method alfo
obtains for Meadows and Paflure Ground, moifi, claiey, or
BURNISHING, the Aaion of fmoothening orpolilhing
a Body, by a violent rubbing it with any thing. Thus
Bookbinders burnib the Edges of their Books, by rubbing
'em with a Dog's Tooth. Gold and Silver are burniih'd
with a Wolf's Tooth, a Dog's Tooth, or the bloody Stone,
Tripoli, a piece of white Wood and Emery. Hence B'ur-
nijher, is a round polimh'd piece of Steel, ferving to fmooth
and give a Luflre to Metals: Of there there are various
Kinds, of various Figures; firait, crooked, ec. Half B ur-
nihers, are us'd to folder Silver, as well as to give it a
Deer are faid to burnijb their Heads, when rubbing off
a white downy Skin from their Horns againfi a Tree, they
thrufi 'em into a reddifh Earth, to give 'em a new Colour
and Luffre.
BURR, or BURR-DOCK, is an Herb, whofe broad
Leaves, Roots, and Seeds, are fometimes us'd in Phyfick.
BURR-PUMP, or Bildge Pump, a kind of Pump lo call'd,
becaufe it holds much Water; fee PUMP.
BURSARS, in Scotland, are Youths chofen, and fent as
Exhibitioners to the Univerfities, one each Year, by each
Presbytery; by whom they are to be fubfifted for the Space
of four Years, at the Rate of Ioo 1. per Annum, Scots.
BUSHEL, a Meafure of Capacity for things Dry; as
Grains, Pulfe, dry Fruits, Uec. The B glhBujhel contains
4 Pecks, or 8 Gallons, or T of a Quarter. See MEASURE.
At Paris, the RBuJhel is divided into two half !BR -
els; the half .BuJhel into two Quarts; the Quart into
two half Quarts; the half Quart into two Litrons; and
the Litron into two half Litrons. Bya Sentence of the Pro-
voff of the Merchants of Paris, the Bujhel is to be eight
Inches, two Lines and a half high, and ten Inches in Dia-
meter5 the Quart four Inches nine Lines highi and fix
Inches nine Lines wide; the half Quart four Inches three
Lines high, and five Inches -Diameter; the Litron three
Inches and a half high, and three Inches ten Lines in Dia-
meter. Three Bufluhels make a Minot, fix a Mine, Iz a
Septier, and 144 a Muid: See MUID.  In other Parts of
France the !BuJhel varies: 14   u . hels of .Anboife and
71ours, make the Paris Septier. zo fBuhels of Avignon,
make three Paris Septiers ;, 20o jBujhels of 'Blois, make one
Paris Septier; 2 Bujhels of B'ourdeaux, make one Pa-
ris Septier; 32 Bujhels of Rochel, make I9 Paris Sep-
tiers, Note, Oats are meafur'd in a double Proportion to
other Grains; fo that 24e fhels of Oats make a Septierj
and 248 a Muid. The fBujhel of Oats is divided into four
Picotins, the Picotin into two half Quarts, or four Litrons.
For Salt, four BuJhels make one Minot, and fix a Septier.
For Coals, eight .'u4hels make one Minot, i6 a Mine, and
320 a Muid. For Lime, 3 yjuhels make a Minot, and
48 Minots a Muid.
ZDu Cange derives the Word from .BRucllus, or Buftellusi
or Bifellus, a diminutive of .Bz, or !Buza, us'd in the
corrupt Latin for the fame thing. Others derive it from
8uffilus, an Urn wherein Lots are cafe.
-IBUSKIN, Cothurnus, a kind of Stocking among the
Antients, in manner of a little Boot, covering the Foot and
Mid-leg, and ty'd beneath the Knee ; very rich and fine,
and used principally on the Stage by the Abtors in Trage-
dy. The Buskzn is faid to have been firft introduc'd by
Sophocles: It was of a Quadrangular Form, and might be
wore indifferently on either Leg. It was fo thick, as by
means hereof, Men of ordinary Stature might be rais'd to
the Pitch and Elevation of the Heroes they perfonated:
In which it was diflinguimh'd from the Sock, wore in Co-
medy; which was a low, popular Drefs. Dempfler ob-
ferves, that it was not Aaors alone who wore the Buskin,
but Girls likewife us'd 'em to raife their Height; Travellers
and Hunters to defend themfelves from the Mire, Wjc. As
the Buskin was the diftinguibhing Mark of Tragedy on the
Stage, we find it in Claffick Authors frequently us'd to fig-
nify Tragedy it felf.
BUST, or BUSTO, in Sculpture, &c. a Term us'd for
the Figure, or Portrait of a Perfon in Relievo; fitewing only
the Head, Shoulders, and Stomach; the Arms being lopp'd
off: ordinarily placed on a Pedeffal, or Cofole. Felibten
obferves, that tho in Painting one may fay a Figure appears.

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