213 
M O D 
M O D 
MOD 
mis, datisi, bocardo, ferison. The ufe and 
effect oi which words lie wholly in the sylla- 
bles, and the letters of which the syllables 
consist ; each word, for instance, consists of 
three syllables, denoting the three proposi- 
tions of a syllogism, viz. major, minor, and 
conclusion: add, that the letters «i each syl- 
lable are either vowel* or consonants; the 
vowels are A, which denotes an universal af- 
firmative; E, an universal negative; 1, a 
particular affirmative; and O, a particular 
negative: thus, Barbara is a syllogism or 
mood of the first figure, consisting of three 
universal affirmative propositions: Baralip, 
one of the fourth figure, consisting of two 
universal affirmative premises, and a particu- 
lar affirmative conclusion. The consonants 
are chiefly of use in the reduction of syllo- 
gisms. The indirect mood, is that wherein 
the conclusion is not inferred immediately 
from the premises, but follows from them by 
means of a conversion; as, “ Every animal 
is a living thing, every man is an animal; 
therefore some living thing is a man.” 
Mod?., in music, a particular system, or 
constitution of sounds, by which the octave 
is divided into certain intervals, according to 
the genus. The doctrine of the antients 
respecting modes is rendered somewhat ob- 
scure, by the difference among their authors 
as to the definitions, divisions, and names of 
their modes. Some place the specific vari- 
ations of tones, or modes, in the manner of 
division, or order of the concinnous parts; 
and others merely in the different tension of 
the whole: i. c. as the whole series of notes 
are more acute or grave, or as they stand 
higher or lower in the great scaie of sounds. 
MODEL, in a general sense, an original 
pattern, proposed tor any one to copy or imi- 
tate. This word is particularly used in 
building, for an artificial pattern made in 
wood, stone, plaster, or other matter, with 
all its paths and proportions, in order for the 
better conducting and executing some great 
work, and to give an idea of the effect it will 
have in large. In all great buildings, it is 
much the surest way to make a model in re- 
lievo, and not to trust to a bare design or 
draught. There are also models for the 
building of ships, &c. and for extraordinary 
staircases, &c. 
They also use models in painting and sculp- 
ture; whence, in the academies, they give 
the term model to a naked man or woman, 
disposed in several postures, to afford an op- 
portunity to the scholars to design him in va- 
rious views and attitudes. 
Models in imitation of any natural or arti- 
ficial substance, are most usually made by 
means of moulds composed of plaster of 
Paris. For the purpose of making these 
moulds, this kind of plaster is much more 
lit than any other substance, on account of 
the power it has of absorbing water, and soon 
condensing into an hard substance, even after 
it has been rendered so thin as to be of the 
consistence of cream. This happens in a 
shorter or longer time, as the plaster is of a 
better or worse quality ; and its good or bad 
properties depend very much upon its age, 
to which, therefore, particular regard ought 
to be had. it is sold in the shops at very dif- 
ferent prices; the finest being made use of 
for casts, and the middling sort for moulds. 
It may be- very easily coloured by means of 
almost any kind of powder excepting what 
contains an alkaline salt; tor this would che- 
mically decompose the substance of it, and 
render it unfit for use, the gypsum of plaster 
being a sulpha! of lime, which would be de- 
compose-! by the alkali precipitating the lime. 
A very considerable quantity of chalk would 
also render it soft and useless, but lime 
hardens it to a great degree. The addition 
of common size will likewise render it much 
harder than if mere water is made use of. In 
making either moulds or models, however, 
we must be careful not to make the mixture 
too thick at first; for if this is done, and 
more water added to thin it, tne composition 
must always prove brittle, and of a bad qua- 
lity. 
The particular manner of making models 
(or casts, as they are also called) depends en 
the form of the subject to be taken. The 
process is easy where the parts are elevated 
only in a slight degree, or where they form 
only a right or obtuse angle with the princi- 
pal surface from which they project; 'but 
where the parts project in smaller angles, or 
form curves inclined towards the principal 
surface, the work is more difficult. This ob- 
servation, however, holds good only with re- 
gard to hard and inflexible bodies; for such 
as are soft may often be freed from the 
mould, even though they have the shape last 
mentioned. But though this is the case with 
the solt original substance, it is not so with 
the inflexible model when once it is cast. 
The moulds are to be made of various de- 
grees of thickness, according to the size of 
the model to be cast; and may be from half 
an inch to an inch, or, if very large, an inch 
and an half. Where a number of models 
are to be taken from one mould, it will like- 
wise be necessary to have it of a stronger con- 
texture than where only a few are required, 
for very obvious reasons. 
It is much more easy to make a mould 
for any soft substance than a rigid one, as in 
any of the viscera of the animal body: for 
the fluidity of the mixture makes it easily ac- 
commodate itself to the projecting parts of 
the substance; and as it is necessary to inflate 
these substances, they may be very readily 
extracted again, by letting out the air which 
distended them. 
When a model is to be taken, the surface 
of the original is first to be greased, in order 
to prevent the plaster from sticking to it; 
but il the substance itself is slippery, as is the 
case with the internal parts of the human bo- 
dy, this need not be done: when necessary, 
it may be laid over with linseed oil by means 
of a painter’s brush. The original is then to 
be laid on a smooth table, previously greased, 
or covered with a cloth, to prevent the plas- 
ter sticking to it ; then surround the original 
with a frame or ridge of glazier’s putty, at 
such a distance from it as will admit the plas- 
ter to rest upon the table on all sides of the 
subject for about an inch, or as much as is 
sufficient to give the proper degree of 
strength to the mould. A sufficient quan- 
tity of plaster is then to be poured as uni- 
formly as possible over the whole substance, 
until it is every where covered to such a 
thickness as to give a preper substance to 
the mould, which may vary in proportion to 
the size. The whole must then be suffered 
to jrejoai# U) pojnlitioy till the plaster Jans 
attained its hardness: when the frame i# 
taken away, the mould may be inverted, and 
the subject removed from it; and when the 
plaster is thoroughly dry, let it be veil sea- 
soned. 
Having formed and seasoned the moulds, 
they must next be prepared for the casts by 
greasing the inside of them with a mixtu e of 
olive oil and lard in equal parts, and then 
tilled with line fluid plaster, and the plane of 
the mould formed by its resting on the sur- 
tace of the table, covered to k- sufficient 
thickness with coarse plaster, to form a strong 
basis or support for the cast where this sup- 
port is requisite, as is particularly the case 
where the thin and membranous parts of the 
body are to be represented. After the plas- 
ter is poured into the mould, it must be suf- 
fered to stand until it has acquired the great- 
est degree of hardness it will receive; after 
which the mould must he removed: but 
this is attended with some difficulty when 
the shape of the subject is unfavourable; and 
in some cases the mould must be separated 
by means of a small mallet and chisel. If 
by these instruments any parts oi' the model 
should be broken off, they may be cemented 
by making the two surfaces to be applied to 
each other quite wet; then interposing be- 
twixt them a little liquid plaster; and lastly, 
the joint smoothed, after being thoroughly 
dry. Any small holes that may be made in 
the mould can be tilled up with liquid plas- 
ter, after the sides of them have been tho- 
roughly wetted, and smoothed over with the 
edge of a knife. 
In many cases it is altogether impractica- 
ble to prepare a mould of one pitce for a 
whole subject; and therefore it must be con- 
sidered how' this can be done in such a man- 
ner as to divide the mould into the fewest 
pieces. This may be effected by making 
every piece cover as much of the pattern as 
possible, without surrounding such project- 
ing parts, or running into such hollow’s as 
would not admit a separation of the mould. 
Where any internal pieces are required, they 
are first to be made; and then the outer 
pieces, after the former have become hard. 
Besides the models which are taken from, 
inanimate bodies, it has been frequently at- 
tempted to take the exact resemblance of 
people while living, by using their face as the 
original of a model, whence to take a mould,; 
and the operation, however disagreeable, lias 
been submitted to by persons of the highest 
ranks in life. A considerable difficulty oc- 
curs in this, however, from the person’s be- 
ing apt to shrink and distort his features 
when the liquid is poured upon him; nei- 
ther is he altogether without danger of suf- 
focation, unless the operator well under- 
stands his business. ♦ 
To avoid the former inconvenience, it will 
be proper to mix the plaster w ith w arm in- 
stead of cold water, by which means the per- 
son will be under no temptation to shrink; 
and to prevent any danger of a fata! acci- 
dent, the following method is to be practised : 
Having laid the person horizontally on his 
back, tine head must first be raised by means 
of a pillow to the exact position in which it is 
naturally carried when the body is erect ; 
then the parts to be represented must be 
very thinly covered over with fine oil of al- 
monds, by mean# of a painter’s brush : the 
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