PLI
pAlngg thro' that flame, fparkle and become ignite4 and if  I
theyare receivd on a white paper placed underneath the final-
ec particles will be ifound round and friabl reduced t6 fcorim,  1
no way differing from  the little globules of fcorified fleel,
which are firuck off from the flint and fieel in giving fire by
their coIlifion.
When we have occafion to melt larger parcels of Reel or iron,
we are obliged to have recourfe to fuch fubftbrces to mix with
them as will, replace with increafe that inflammable matter
which. tbe fire drives off: the fubftances of this kind are corm-
mon Ulphur, orpiment, arfenic, and the like; and by means
of thef  it is foon made to run like lead. Memoires Acad.
Scien ;PS". 1736.
Mr. Reanmur having given there hints for the underflanding
the occafion of iron's being found fcorified by the fhort heat it I
receivesfrom  the collision of flint and fleel, proceeds to ac-
count for the reafon why iron yields fewer fparks with fint
than it does with fteel.
On this occafion he obferves, that he accidentally had difcover-
ed a new phofphorus of iron, in giving the procefs of which,
great light would be thrown into this fubjedt: the method of
making it was this, having melted fome antimony in a cruci-
ble, he threw in at feveral times, twice the quantity of iron
reduced into thin fcales; the whole foon melted together, and
became one fluid mafs; when this had been caft into a mould
-and was become cold, it afforded a long train of fparks on be-
ing filed with a common coarfe file.  The fparks were much
larger than thofe produced by a collifion of fint and fleel, and
the larger of them fet fire to the paper placed to receive them;
but upon examination, thefe were all found to be melted in
the manner of the Sparkling particles ftruck off from fteel, not
only burnt, but melted, and that more perfetly than the others
from the common collifion withflint. If after all this, it be
ask'd, why fReel yields greatly more numerous fparkles than
iron ? the anfwer is plain, that the difference of hardnefs alone
is fufficient to occafion it ; but granting even that fReel and
iron were of equal hardnefs, fteel has the fame advantage of
iron in this refpe&, that the before mentioned mixture of iron
with antimony has over plain iron, in that it contains greatly
more of the inflammable matter than the iron does, and this in-
flammable matter is alfo more equally diftributed thro' all its
fu4rface.
It may alfo be judged, that the flint not only contributes by
its hardnefs to the fending off the fparks, but alfo by its fulphur;
what the blow diflodges from it of this kind, and puts in vio-
lent motion, probably having no fimall effe6t both in the fu-
fion and fcorification of the metal. That all flints contain a
large quantity of fulphur is plain, from the fulphureous fmell
they afford on being firuck together; and the fparks, which are
produced by firiking iron againft iron are probably affealed in
the fame manner, by the fulphur of the metal diflodged from
the adjoining parts by the blow.
One great proof of the fparks being melted and rendered glo-
bular by means of the fulphur of the flint is, that fparks may
be firuck from fteel, in the fame manner by glafs as by flint,
but in lefs quantity; thefe having been received on a paper,
were examined by Mr. Reaumur, and were found to be fco-
rix, of an irregular figure, having never been melted,
and therefore never reduced to the globular fhape of the others.
In regard to the great change wrought in iron by this opera-
tion, or its being according to the words of Kemp destroyed,
no longer retaining its great characaer of being attraated by the
loadftone, Mr. Reaumur willing to try the experiment be-
fore he reafoned upon it, found this affertion not to be a faat,
or at leaft not a general one.
All the feveral kinds of fparks which he mentions, thofe pro-
duced by the common collision of flint and fleel, thofe by
dropping feel filings thro' the flame of a lamp, and even thofe
from the filing of the antimoniated iron, all as readily anfwer-
ing to the loadifone as common filings of iron; fo that if this
cafe fometimes happen, and iron be liable thus to be deftroyed,
it is however no general fa&, but a very rare and extraordi-
nary one.  Memoris Acad. Par. 1736.
FLINTS, in the glWaf trade.  The way of preparing fints for
the niceft operations in the glafs trade is this. Chufe the hard-
eft fints, fuch as are black and will refift the file, and will
grow white when calcined in the fire. Cleanfe thefe of the
white cruft that adheres to them, then calcine them in a flrong
fire, and throw them while red hot into cold water; wafh off
the anhes that may adhere to them, and powder them in an
iron mortar, and fift them through a very fine Sieve; pour
  upon this powder fome weak aqua fortis, or the phlegm of
  aqua fortis, to difiolve and take up any particles of iron it may
  have got from the mortar; ftir this mixture feveral times,
  then let it refd, and in the morning pour off the liquor, and
  warn the powder feveralrtimes with hot water, and afterwards
  dry it for ufe. You will thus have a powder for making the
  pureft glafs as perfealy fine and faultlefs, as if you had uted
  rock cryftal itfif. Cramer's Art of affaying metals, p. 438.
  The waihing off the ferrugineous particles with aqua fortis is
  uut necelliry, when the glafs intended to be made is to be ting-
                            FLOF
 ed witWroi afteards; bat whnmeant tik, pi wuhite,
 thiois th methodto be filre Offi ceedi   ,  Xo  , i
 .Baking of FLINT. - The art of cutting or rather braking
 liYs ftones into unifyr figures,5 was by fe.Xib
 one of the arts now loft . That it wtas 1    _    7
 pear from the antient Bridewell at Norwich, fitmhie
 of the Auffin-friars at Canterbury, that of St.
 at Colchefter, and the gate near Whiteh*&Mi tW
 But that the art is ot lo, and that the Frenchow  Ac -
 pears from the platform on the top of the royal obi~rVatory)at
 Paris, which inftead.of being leaded, is paved with  , in
 the manner here mentioned. But we know not that this art
 is any where defuribed.  Phil. Tmanf N'. 477. P. 52,, and
 Note ibid.   --                f..                       El
9i of FLINTS, a name given by obme to a preparation made
  of four ounces of flints calcined and powdered and mixed with
  twelve ounces of falt of tartar; thefe being melted together
  by a firong fire, run into a glafs, which being afterwards pow-
  dered and fet in a cellar, runs into an oil per deliquium ; with
  this and the calx of any metal is prepared, one of the metal-
  lic vegetations. See VEGETATIONS metallic.
FLOATING (Cycl)-FLoATING-bridge, a bridge confiffing of
  feveral boats covered with planks; which ougi* to be, foblidly
  framed, as to bear both horfes and cannon. See BRIDGE,
  Cycl. and Supp..
FLOATING !IIands. See ISLAN{DS.
FLOOD (Cycl) - FLOoD-mark, the mark which the fea makes
  on the Ihoar, at flowing water, and the higheft tide: it is al-
  fo call'd high-water mark.
Sand FLOOD. See SAND.
FLOOKING, a term ufed in mining to exprefs a peculiarity in
;the load of a mine. The load or quantity of ore is frequent-
  ly intercepted in its courfe, by the croiling of a vein of earth
  or flone, or fome different metallic fubifance; in which cafe
  the load is moved to one fide, and this tranfient part of the
  land is called a floking. See MINE,
FLOOR (Cycl) -FLOOR-timber, in a fhip. See TiMBER.
FLORAL leaf, among botanifls. See LEAF.
FLORES argenti, in natural Hiflory, a name given by forne to
  the earth, called by the generality of authors, lac lunae. It
  has both thefe names from its being fuppofed to partake of the
  nature of filver.  See the article LAC lUng, Cycl. and
  Supp1.
FLORES Martiales, a name given to a preparation of the nature
  of what was formerly called ens veneris. Thefe flowers are
  thus prepared; take of waihed colcothar or green vitriol, or
  of iron filings one pound; of fal armoniac, two pounds; nmix
  them, and fublime them in a retort, and mixing again the
  bottom with the flowers, renew the fublimation till the flowers
  acquire a beautiful yellow colour. To the refidue may be ad-
  ded half a pound of frefh fal armoniac, and the fublimation
  repeated, and the fame procefs may be continued as long as the
  flowers arife duly coloured. Pemberton's Lond. Difp. p. 2 15.
FLORIST, Floroa, in botany, an autbor who writes what
   is called the flora of any particular place, that is, a catalogue
   of the plants and trees which are found fpontaneoufly growing
   there. The flora laponica of Linnaeus, and flora virginiea of
   Gronovious, are works of this kind; and thefe authors, as the
   authors of thofe works, are properly called flori/a'. Linn.
   Fundam. Bot. p. I.
FLORUS, in zoology, a name by which Aldrovand and fome
   other authors have called the bird commonly known with us
   by the name of the whinchat, a kind of the aenanthe or fal-
   low-finch. Aidrovand, de Avibus. See WHINCHAT.
FLOS, the flower of a plant. It is to be obferved that the an-
   tients fometimes called the flamina or threads in the center of
   flowers, the fios, and not the petals which we ufually call fo.
   Without understanding this, it is not poflible to underftand
   many paflages in their writings. We find in Aurelian, the
   rofe called a yellow flower flanding in a purple husk; it is plain
   by this, that he meant the threads in the middle of that flow-
   er, which are of a fine yellow, and are very numerous, by the
   word flower; and calls the fine purple petals which we efteem
   the flower, only the husk of the flower i in this fenfe Virgil is
   explained to mean the common baum by the name ameilo;
   he fays it has a yellow flower and purple leaves at the bottom,
   and they fuppofe that he meant the ftamina or threads which
   in the baum are yellow, by the name flower; and the calyx
   or cup of the flower which is a purple, by his exprefsion of
   leaves at the bottom. The antients in general do not feem,
   determined as to-what they would have underftood by the
   word fios. In the narciffus, Pliny calls the cup that yellow
   part which occupies the center, and the whitifh leaves that
   furround it the flower. Pliny has been cenfured for calling
   this part of the flower the cup, but- he does not by this mean
   to confound it with the green leaves in the generality of plants
   which furround the flower, but he calls it thus in refemblance
   to the cups out of which they drank, in their feftivals.
FLOS arriv. See the articde-Is.
FLOS ambarvalis, in botany, a name given by fome to the poly-
   gala or milkwort. aUrm. Cat. p. 450.
                                                          FL OS