388 ' MAE 
rendered null the elections of his department, with thofe 
of many others. He died, almoft in indigence, in De¬ 
cember 1799, in the feventy-feventh year of his age; leav¬ 
ing a widow and two young children without fupport. 
Marmontel defervedly holds a high rank amongft mo¬ 
dern French authors. Warm and eloquent on grave and 
elevated topics, eafy and lively on light ones, ingenious, 
inventive, and varied, full of good fenfe and animated 
with fentiment, he addrefles himfelf with almolt equal 
fuccefs to the heart, the imagination, and the judgment. 
Scarcely any work of the age was more popular than his 
Contes Moravx, which contain many charming (Tories de¬ 
lightfully told. The Englifii reader, however, Ihould he 
apprifed that they are not properly rendered “ Moral 
Tales,” fince the morality of them is very ambiguous; 
though in general they inculcate valuable and ufeful lef- 
fons. Thefe, the Belifaire and Incas, are belt known to 
foreigners. His poetical works are little read abroad, 
and feem lefs Valued in France than his profe. Some of 
his didaCtic works are much elteemed, efpecially his 
Courfe of Literature inferted in the Encyclopedic. Since 
his death, belides his own Memoirs, there have appeared 
Memoirs of the Regency of the duke of Orleans, printed 
from his manufcript, in 2 vols. umo. 
MAR'MOR,yi [Lat. from Gr. to (iiine or 
glitter.] Marble; in mineralogy, a genus of calcareous 
earth — Confiding of carbonnt of lime, carbonic acid gas, 
and water; hardilh, meagre to the touch, of a common 
form, lightifl), compoling whole mountains, or the greater 
part of them, or in detached pieces; burning into quick¬ 
lime, foluble for the greater part in acids, with effervef- 
cence. 
The term marble was originally applied to any mineral 
fubltance capable of receiving a polifh, and ufed, in con- 
fequence of the beauty of its appearance, for ornamental 
purpofes : in the prefent in dance it is applied to fitch mi¬ 
neral fubllances only, as from the nature and porportions 
of their conftituent parts are judly denominated carbonats 
of lime. The term Imejlone all'o, which ftrictly fpeaking 
is applicable to any natural compound containing a 
large proportion of that earth, is here ufed to exprefs 
thole natural compounds only, in which lime combined 
with carbonic acid is the principal condituent part. In 
this fenfe, then, marbles andilimeitones are with refpeCt to 
their chemical analyfis the fame ; they differ only in their 
tiles and external characters. Almoft all of them con¬ 
tain fome portion of iron ; many contain clay alfo; and, 
where the proportion of clay is confiderable, the fub- 
ltance poffeffes thofe properties which conftitute a marl. 
Marbles are eafily diftinguilhable from gypfeous and 
calcareous aiabafters, with which they are frequently con¬ 
founded ; from the former by the application of fome di¬ 
luted nitric or muriatic acid, which produces a ftrong ef- 
fervefcence, by expelling the carbonic acid; from the 
latter (which belong to ftalaCtitical limeftone, and are 
therefore acted upon in the fame manner by the acids) 
by inferior hardnefs, a flighter degree of tranllucidity, 
and, if coloured, by the ablence of regularity in the (tripes 
and undulations that charaClerife the calcareous alabalter ; 
nor is the latter ever found in mafl'es of conliderable di¬ 
men lions. 
The fpeeific gravity of marble varies in the fame man¬ 
ner as that of the different varieties of common limeftone, 
whence no distinctive character can be derived from it : 
Wallerius and Gmelin ftate the fpeeific gravity of the 
former ro be lefs, while others confider it as greater, than 
that of common limeftone; but, according to Gerhard 
and other writers, it is, on the whole, equal in both. 
Some granular marbles, when cut into thin (labs, ex¬ 
hibit a degree of elallicity or flexibility, fimilar to that of 
the well-known fandftone (Arennrius fltxilis) found in 
Brafil, riiis phenomenon was firft oblerved in fome 
pieces of marble preferved in the palace of prince Borg- 
hefe at Rome. But afterwards another marble, having 
the fame property, was difeovered by Fleuriau de Bellevue, 
L M O R. 
in the Val-Levantine of mount St. Gothard. Dolomieu 
(who deferibed the Borghefe marble) is of opinion that 
this property is owing to a ftate of deficcation which has 
leffened the adherence of the molecules of the (tones ; 
and Fleuriau de Bellevue has proved this conjecture to 
be well founded, not only by the appearance and nature 
of the (tone he difeovered on St, Gothard, hut alfo by 
his imparting the fame property to feveral inflexible va¬ 
rieties of marble by merely expofmg them to fuch a de¬ 
gree of heat as produced complete deficcation. Some 
wrought granular (ftatuary) marbles acquire a fimilar 
property after a long expofure to the action of the atmof- 
phere and the folar rays; a circumftance which fome- 
times takes place in Itatues, caufing' thereby the more 
projecting parts to exfoliate, and to crumble to pieces. 
As to the manner in which (white) marble is produced, 
we have fome curious particulars in the Phil Tranf. 
vol. lx. p-47. The writer, Mr. Rafpe, F.R.S. gives an 
account of fome obfervations inane by the abbe Vegni ori 
the hot mineral waters of St. Philip, at Radicofani in 
Tulcany, on the road from Florence to Rome. 1. The 
abbe traced the lource of thefe waters to a (mail hill 
(which appeared to be entirely compofed of white mar¬ 
ble), from which they flowed in feveral rivulets. 2. He 
found tint thefe waters abounded in fuiphur. 3. He 
found that they depolited a great quantiy of (hining 
white tophus, with which not only the Tides of the chan¬ 
nels, along which they flowed, became incrufted, but like- 
wife all kinds of hard bodies that were thrown into them ; 
and this in fuch manner, that, when the tophus was 
dexteroufly broken off, it retained exaCtly the form and 
fiiape of the bodies on which it had been depolited. 4. 
He further obferved, that when the old channels became 
choked up by the accumulation of tophus, or in any other 
manner, the water (till continued to depolit the tophus 
in its new and more elevated channels. Hence .lie abbe 
was led to infer, 1. That the whole of that hill, from 
which thele hot mineral waters iffued, was formed by the 
luccelTiv.- depofitiou of this (hilling white tophus. 2. 
That this tophaceous precipitate might be rendered fub- 
fervient to the arts, provided it were caught upon moulds. 
Accordingly the abbe let on foot an undertaking of this 
kind, which lucceeded very well. Models of various 
kinds of fculpture formed of gypfum, well varniflied and 
befmeared with oil or greafe, being placed in the currents 
of thele hot fprings, became incrufted with tophus to the 
thicknefs of two lines in the ipace of fix days ; and in this 
manner were obtained bas reliefs, medallions, architec¬ 
tural ornaments for doors, windows, chimneys, See. which 
in many inltances looked like real fculpture, and Teemed 
to be formed of the pureft Carrara marble. Mr. Rafpe 
adopts the opinion that all white marble is a precipitate 
from water like the tophus of the hot fprings above men¬ 
tioned. 
The various tints of marbles are generally produced 
by oxyds of iron, the folution of which has, either wholly 
or partially, penetrated the mafs previous to its complete 
induration. Blue and green marbles often owe their 
tints to minute particles of hornblende; this is the cafe, 
for inftance, with the (late-blue variety called turckino , 
and with fome green German marbles. The black va¬ 
rieties are coloured by charcoal, and alfo by bitumen, 
when they pals into ltinkftone. In marbles containing 
petrifactions, thefe appear foinetimes to have derived 
their colour from the fame fluid which coloured the mal's; 
while at other times the colour of the ground is quite dif¬ 
ferent from that of the petrifactions it contains. 
There are fourteen fpecies of marble, belides many va¬ 
rieties. 
1. Marmor bammites, or ketten-ftone : opake, without 
lultre, compadt, coniifting of accreted round granulations. 
Found in It ratified mountains in various parts of Britain, 
particularly at Ketten in Rutlandfhire, and at Bath ; in 
Saxony, Brunfwick, France, Swifferland, See. always in 
large maffes, with rarely the remains of animal fubllances. 
3 Colour 
