The Ten Books on Architecture
BOOK I
PREFACE
1. While your divine intelligence and will, Imperator Caesar,
were engaged in acquiring the right to command the world, and while
your fellow citizens, when all their enemies had been laid low by
your invincible valour, were glorying in your triumph and
victory,—while all foreign nations were in subjection awaiting your
beck and call, and the Roman people and senate, released from their
alarm, were beginning to be guided by your most noble conceptions
and policies, I hardly dared, in view of your serious employments,
to publish my writings and long considered ideas on architecture,
for fear of subjecting myself to your displeasure by an
unseasonable interruption.
2. But when I saw that you were giving your attention not
only to the welfare of society in general and to the establishment
of public order, but also to the providing of public buildings
intended for utilitarian purposes, so that not only should the
State have been enriched with provinces by your means, but that the
greatness of its power might likewise be attended with
distinguished authority in its public buildings, I thought that I
ought to take the first opportunity to lay before you my writings
on this theme. For in the first place it was this subject which
made me known to your father, to whom I was devoted on account of
his great qualities. After the council of heaven gave him a place
in the dwellings of immortal life and transferred your father's
power to your hands, my devotion continuing unchanged as I
remembered him inclined me to support you. And so with Marcus
Aurelius, Publius Minidius, and Gnaeus Cornelius, I was ready to
supply and repair ballistae, scorpiones, and other artillery, and I
have received rewards for good service with them. After your first
bestowal of these upon me, you continued to renew them on the
recommendation of your sister.
3. Owing to this favour I need have no fear of want to the
end of my life, and being thus laid under obligation I began to
write this work for you, because I saw that you have built and are
now building extensively, and that in future also you will take
care that our public and private buildings shall be worthy to go
down to posterity by the side of your other splendid achievements.
I have drawn up definite rules to enable you, by observing them, to
have personal knowledge of the quality both of existing buildings
and of those which are yet to be constructed. For in the following
books I have disclosed all the principles of the art.
CHAPTER I
THE EDUCATION OF THE ARCHITECT
1. The architect should be equipped with knowledge of many
branches of study and varied kinds of learning, for it is by his
judgement that all work done by the other arts is put to test. This
knowledge is the child of practice and theory. Practice is the
continuous and regular exercise of employment where manual work is
done with any necessary material according to the design of a
drawing. Theory, on the other hand, is the ability to demonstrate
and explain the productions of dexterity on the principles of
proportion.
2. It follows, therefore, that architects who have aimed at
acquiring manual skill without scholarship have never been able to
reach a position of authority to correspond to their pains, while
those who relied only upon theories and scholarship were obviously
hunting the shadow, not the substance. But those who have a
thorough knowledge of both, like men armed at all points, have the
sooner attained their object and carried authority with
them.
3. In all matters, but particularly in architecture, there
are these two points:—the thing signified, and that which gives it
its significance. That which is signified is the subject of which
we may be speaking; and that which gives significance is a
demonstration on scientific principles. It appears, then, that one
who professes himself an architect should be well versed in both
directions. He ought, therefore, to be both naturally gifted and
amenable to instruction. Neither natural ability without
instruction nor instruction without natural ability can make the
perfect artist. Let him be educated, skilful with the pencil,
instructed in geometry, know much history, have followed the
philosophers with attention, understand music, have some knowledge
of medicine, know the opinions of the jurists, and be acquainted
with astronomy and the theory of the heavens.
4. The reasons for all this are as follows. An architect
ought to be an educated man so as to leave a more lasting
remembrance in his treatises. Secondly, he must have a knowledge of
drawing so that he can readily make sketches to show the appearance
of the work which he proposes. Geometry, also, is of much
assistance in architecture, and in particular it teaches us the use
of the rule and compasses, by which especially we acquire readiness
in making plans for buildings in their grounds, and rightly apply
the square, the level, and the plummet. By means of optics, again,
the light in buildings can be drawn from fixed quarters of the sky.
It is true that it is by arithmetic that the total cost of
buildings is calculated and measurements are computed, but
difficult questions involving symmetry are solved by means of
geometrical theories and methods.
5. A wide knowledge of history is requisite because, among
the ornamental parts of an architect's design for a work, there are
many the underlying idea of whose employment he should be able to
explain to inquirers. For instance, suppose him to set up the
marble statues of women in long robes, called Caryatides, to take
the place of columns, with the mutules and coronas placed directly
above their heads, he will give the following explanation to his
questioners. Caryae, a state in Peloponnesus, sided with the
Persian enemies against Greece; later the Greeks, having gloriously
won their freedom by victory in the war, made common cause and
declared war against the people of Caryae. They took the town,
killed the men, abandoned the State to desolation, and carried off
their wives into slavery, without permitting them, however, to lay
aside the long robes and other marks of their rank as married
women, so that they might be obliged not only to march in the
triumph but to appear forever after as a type of slavery, burdened
with the weight of their shame and so making atonement for their
State. Hence, the architects of the time designed for public
buildings statues of these women, placed so as to carry a load, in
order that the sin and the punishment of the people of Caryae might
be known and handed down even to posterity.
6. Likewise the Lacedaemonians under the leadership of
Pausanias, son of Agesipolis, after conquering the Persian armies,
infinite in number, with a small force at the battle of Plataea,
celebrated a glorious triumph with the spoils and booty, and with
the money obtained from the sale thereof built the Persian Porch,
to be a monument to the renown and valour of the people and a
trophy of victory for posterity. And there they set effigies of the
prisoners arrayed in barbarian costume and holding up the roof,
their pride punished by this deserved affront, that enemies might
tremble for fear of the effects of their courage, and that their
own people, looking upon this ensample of their valour and
encouraged by the glory of it, might be ready to defend their
independence. So from that time on, many have put up statues of
Persians supporting entablatures and their ornaments, and thus from
that motive have greatly enriched the diversity of their works.
There are other stories of the same kind which architects ought to
know.
7. As for philosophy, it makes an architect high-minded and
not self-assuming, but rather renders him courteous, just, and
honest without avariciousness. This is very important, for no work
can be rightly done without honesty and incorruptibility. Let him
not be grasping nor have his mind preoccupied with the idea of
receiving perquisites, but let him with dignity keep up his
position by cherishing a good reputation. These are among the
precepts of philosophy. Furthermore philosophy treats of physics
(in Greek [Greek: physiologia]) where a more careful knowledge is
required because the problems which come under this head are
numerous and of very different kinds; as, for example, in the case
of the conducting of water. For at points of intake and at curves,
and at places where it is raised to a level, currents of air
naturally form in one way or another; and nobody who has not
learned the fundamental principles of physics from philosophy will
be able to provide against the damage which they do. So the reader
of Ctesibius or Archimedes and the other writers of treatises of
the same class will not be able to appreciate them unless he has
been trained in these subjects by the philosophers.
8. Music, also, the architect ought to understand so that he
may have knowledge of the canonical and mathematical theory, and
besides be able to tune ballistae, catapultae, and scorpiones to
the proper key. For to the right and left in the beams are the
holes in the frames through which the strings of twisted sinew are
stretched by means of windlasses and bars, and these strings must
not be clamped and made fast until they give the same correct note
to the ear of the skilled workman. For the arms thrust through
those stretched strings must, on being let go, strike their blow
together at the same moment; but if they are not in unison, they
will prevent the course of projectiles from being
straight.
9. In theatres, likewise, there are the bronze vessels (in
Greek [Greek: êcheia]) which are placed in niches under the seats
in accordance with the musical intervals on mathematical
principles. These vessels are arranged with a view to musical
concords or harmony, and apportioned in the compass of the fourth,
the fifth, and the octave, and so on up to the double octave, in
such a way that when the voice of an actor falls in unison with any
of them its power is increased, and it reaches the ears of the
audience with greater clearness and sweetness. Water organs, too,
and the other instruments which resemble them cannot be made by one
who is without the principles of music.
10. The architect should also have a knowledge of the study
of medicine on account of the questions of climates (in Greek
[Greek: klimata]), air, the healthiness and unhealthiness of sites,
and the use of different waters. For without these considerations,
the healthiness of a dwelling cannot be assured. And as for
principles of law, he should know those which are necessary in the
case of buildings having party walls, with regard to water dripping
from the eaves, and also the laws about drains, windows, and water
supply. And other things of this sort should be known to
architects, so that, before they begin upon buildings, they may be
careful not to leave disputed points for the householders to settle
after the works are finished, and so that in drawing up contracts
the interests of both employer and contractor may be wisely
safe-guarded. For if a contract is skilfully drawn, each may obtain
a release from the other without disadvantage. From astronomy we
find the east, west, south, and north, as well as the theory of the
heavens, the equinox, solstice, and courses of the stars. If one
has no knowledge of these matters, he will not be able to have any
comprehension of the theory of sundials.
11. Consequently, since this study is so vast in extent,
embellished and enriched as it is with many different kinds of
learning, I think that men have no right to profess themselves
architects hastily, without having climbed from boyhood the steps
of these studies and thus, nursed by the knowledge of many arts and
sciences, having reached the heights of the holy ground of
architecture.
12. But perhaps to the inexperienced it will seem a marvel
that human nature can comprehend such a great number of studies and
keep them in the memory. Still, the observation that all studies
have a common bond of union and intercourse with one another, will
lead to the belief that this can easily be realized. For a liberal
education forms, as it were, a single body made up of these
members. Those, therefore, who from tender years receive
instruction in the various forms of learning, recognize the same
stamp on all the arts, and an intercourse between all studies, and
so they more readily comprehend them all. This is what led one of
the ancient architects, Pytheos, the celebrated builder of the
temple of Minerva at Priene, to say in his Commentaries that an
architect ought to be able to accomplish much more in all the arts
and sciences than the men who, by their own particular kinds of
work and the practice of it, have brought each a single subject to
the highest perfection. But this is in point of fact not
realized.
13. For an architect ought not to be and cannot be such a
philologian as was Aristarchus, although not illiterate; nor a
musician like Aristoxenus, though not absolutely ignorant of music;
nor a painter like Apelles, though not unskilful in drawing; nor a
sculptor such as was Myron or Polyclitus, though not unacquainted
with the plastic art; nor again a physician like Hippocrates,
though not ignorant of medicine; nor in the other sciences need he
excel in each, though he should not be unskilful in them. For, in
the midst of all this great variety of subjects, an individual
cannot attain to perfection in each, because it is scarcely in his
power to take in and comprehend the general theories of
them.
14. Still, it is not architects alone that cannot in all
matters reach perfection, but even men who individually practise
specialties in the arts do not all attain to the highest point of
merit. Therefore, if among artists working each in a single field
not all, but only a few in an entire generation acquire fame, and
that with difficulty, how can an architect, who has to be skilful
in many arts, accomplish not merely the feat—in itself a great
marvel—of being deficient in none of them, but also that of
surpassing all those artists who have devoted themselves with
unremitting industry to single fields?
15. It appears, then, that Pytheos made a mistake by not
observing that the arts are each composed of two things, the actual
work and the theory of it. One of these, the doing of the work, is
proper to men trained in the individual subject, while the other,
the theory, is common to all scholars: for example, to physicians
and musicians the rhythmical beat of the pulse and its metrical
movement. But if there is a wound to be healed or a sick man to be
saved from danger, the musician will not call, for the business
will be appropriate to the physician. So in the case of a musical
instrument, not the physician but the musician will be the man to
tune it so that the ears may find their due pleasure in its
strains.
16. Astronomers likewise have a common ground for discussion
with musicians in the harmony of the stars and musical concords in
tetrads and triads of the fourth and the fifth, and with
geometricians in the subject of vision (in Greek [Greek: logos
optikos]); and in all other sciences many points, perhaps all, are
common so far as the discussion of them is concerned. But the
actual undertaking of works which are brought to perfection by the
hand and its manipulation is the function of those who have been
specially trained to deal with a single art. It appears, therefore,
that he has done enough and to spare who in each subject possesses
a fairly good knowledge of those parts, with their principles,
which are indispensable for architecture, so that if he is required
to pass judgement and to express approval in the case of those
things or arts, he may not be found wanting. As for men upon whom
nature has bestowed so much ingenuity, acuteness, and memory that
they are able to have a thorough knowledge of geometry, astronomy,
music, and the other arts, they go beyond the functions of
architects and become pure mathematicians. Hence they can readily
take up positions against those arts because many are the artistic
weapons with which they are armed. Such men, however, are rarely
found, but there have been such at times; for example, Aristarchus
of Samos, Philolaus and Archytas of Tarentum, Apollonius of Perga,
Eratosthenes of Cyrene, and among Syracusans Archimedes and
Scopinas, who through mathematics and natural philosophy
discovered, expounded, and left to posterity many things in
connexion with mechanics and with sundials.
17. Since, therefore, the possession of such talents due to
natural capacity is not vouchsafed at random to entire nations, but
only to a few great men; since, moreover, the function of the
architect requires a training in all the departments of learning;
and finally, since reason, on account of the wide extent of the
subject, concedes that he may possess not the highest but not even
necessarily a moderate knowledge of the subjects of study, I
request, Caesar, both of you and of those who may read the said
books, that if anything is set forth with too little regard for
grammatical rule, it may be pardoned. For it is not as a very great
philosopher, nor as an eloquent rhetorician, nor as a grammarian
trained in the highest principles of his art, that I have striven
to write this work, but as an architect who has had only a dip into
those studies. Still, as regards the efficacy of the art and the
theories of it, I promise and expect that in these volumes I shall
undoubtedly show myself of very considerable importance not only to
builders but also to all scholars.
CHAPTER II
THE FUNDAMENTAL PRINCIPLES OF
ARCHITECTURE
1. Architecture depends on Order (in Greek [Greek: taxis]),
Arrangement (in Greek [Greek: diathesis]), Eurythmy, Symmetry,
Propriety, and Economy (in Greek [Greek: oikonomia]).
2. Order gives due measure to the members of a work
considered separately, and symmetrical agreement to the proportions
of the whole. It is an adjustment according to quantity (in Greek
[Greek: posotês]). By this I mean the selection of modules from the
members of the work itself and, starting from these individual
parts of members, constructing the whole work to correspond.
Arrangement includes the putting of things in their proper places
and the elegance of effect which is due to adjustments appropriate
to the character of the work. Its forms of expression (Greek
[Greek: ideai]) are these: groundplan, elevation, and perspective.
A groundplan is made by the proper successive use of compasses and
rule, through which we get outlines for the plane surfaces of
buildings. An elevation is a picture of the front of a building,
set upright and properly drawn in the proportions of the
contemplated work. Perspective is the method of sketching a front
with the sides withdrawing into the background, the lines all
meeting in the centre of a circle. All three come of reflexion and
invention. Reflexion is careful and laborious thought, and watchful
attention directed to the agreeable effect of one's plan.
Invention, on the other hand, is the solving of intricate problems
and the discovery of new principles by means of brilliancy and
versatility. These are the departments belonging under
Arrangement.
3. Eurythmy is beauty and fitness in the adjustments of the
members. This is found when the members of a work are of a height
suited to their breadth, of a breadth suited to their length, and,
in a word, when they all correspond symmetrically.
4. Symmetry is a proper agreement between the members of the
work itself, and relation between the different parts and the whole
general scheme, in accordance with a certain part selected as
standard. Thus in the human body there is a kind of symmetrical
harmony between forearm, foot, palm, finger, and other small parts;
and so it is with perfect buildings. In the case of temples,
symmetry may be calculated from the thickness of a column, from a
triglyph, or even from a module; in the ballista, from the hole or
from what the Greeks call the [Greek: peritrêtos]; in a ship, from
the space between the tholepins [Greek: (diapêgma)]; and in other
things, from various members.
5. Propriety is that perfection of style which comes when a
work is authoritatively constructed on approved principles. It
arises from prescription [Greek: (thematismô)], from usage, or from
nature. From prescription, in the case of hypaethral edifices, open
to the sky, in honour of Jupiter Lightning, the Heaven, the Sun, or
the Moon: for these are gods whose semblances and manifestations we
behold before our very eyes in the sky when it is cloudless and
bright. The temples of Minerva, Mars, and Hercules, will be Doric,
since the virile strength of these gods makes daintiness entirely
inappropriate to their houses. In temples to Venus, Flora,
Proserpine, Spring-Water, and the Nymphs, the Corinthian order will
be found to have peculiar significance, because these are delicate
divinities and so its rather slender outlines, its flowers, leaves,
and ornamental volutes will lend propriety where it is due. The
construction of temples of the Ionic order to Juno, Diana, Father
Bacchus, and the other gods of that kind, will be in keeping with
the middle position which they hold; for the building of such will
be an appropriate combination of the severity of the Doric and the
delicacy of the Corinthian.
6. Propriety arises from usage when buildings having
magnificent interiors are provided with elegant entrance-courts to
correspond; for there will be no propriety in the spectacle of an
elegant interior approached by a low, mean entrance. Or, if dentils
be carved in the cornice of the Doric entablature or triglyphs
represented in the Ionic entablature over the cushion-shaped
capitals of the columns, the effect will be spoilt by the transfer
of the peculiarities of the one order of building to the other, the
usage in each class having been fixed long ago.
7. Finally, propriety will be due to natural causes if, for
example, in the case of all sacred precincts we select very healthy
neighbourhoods with suitable springs of water in the places where
the fanes are to be built, particularly in the case of those to
Aesculapius and to Health, gods by whose healing powers great
numbers of the sick are apparently cured. For when their diseased
bodies are transferred from an unhealthy to a healthy spot, and
treated with waters from health-giving springs, they will the more
speedily grow well. The result will be that the divinity will stand
in higher esteem and find his dignity increased, all owing to the
nature of his site. There will also be natural propriety in using
an eastern light for bedrooms and libraries, a western light in
winter for baths and winter apartments, and a northern light for
picture galleries and other places in which a steady light is
needed; for that quarter of the sky grows neither light nor dark
with the course of the sun, but remains steady and unshifting all
day long.
8. Economy denotes the proper management of materials and of
site, as well as a thrifty balancing of cost and common sense in
the construction of works. This will be observed if, in the first
place, the architect does not demand things which cannot be found
or made ready without great expense. For example: it is not
everywhere that there is plenty of pitsand, rubble, fir, clear fir,
and marble, since they are produced in different places and to
assemble them is difficult and costly. Where there is no pitsand,
we must use the kinds washed up by rivers or by the sea; the lack
of fir and clear fir may be evaded by using cypress, poplar, elm,
or pine; and other problems we must solve in similar
ways.
9. A second stage in Economy is reached when we have to plan
the different kinds of dwellings suitable for ordinary
householders, for great wealth, or for the high position of the
statesman. A house in town obviously calls for one form of
construction; that into which stream the products of country
estates requires another; this will not be the same in the case of
money-lenders and still different for the opulent and luxurious;
for the powers under whose deliberations the commonwealth is guided
dwellings are to be provided according to their special needs: and,
in a word, the proper form of economy must be observed in building
houses for each and every class.
CHAPTER III
THE DEPARTMENTS OF ARCHITECTURE
1. There are three departments of architecture: the art of
building, the making of timepieces, and the construction of
machinery. Building is, in its turn, divided into two parts, of
which the first is the construction of fortified towns and of works
for general use in public places, and the second is the putting up
of structures for private individuals. There are three classes of
public buildings: the first for defensive, the second for
religious, and the third for utilitarian purposes. Under defence
comes the planning of walls, towers, and gates, permanent devices
for resistance against hostile attacks; under religion, the
erection of fanes and temples to the immortal gods; under utility,
the provision of meeting places for public use, such as harbours,
markets, colonnades, baths, theatres, promenades, and all other
similar arrangements in public places.
2. All these must be built with due reference to durability,
convenience, and beauty. Durability will be assured when
foundations are carried down to the solid ground and materials
wisely and liberally selected; convenience, when the arrangement of
the apartments is faultless and presents no hindrance to use, and
when each class of building is assigned to its suitable and
appropriate exposure; and beauty, when the appearance of the work
is pleasing and in good taste, and when its members are in due
proportion according to correct principles of
symmetry.
CHAPTER IV
THE SITE OF A CITY
1. For fortified towns the following general principles are
to be observed. First comes the choice of a very healthy site. Such
a site will be high, neither misty nor frosty, and in a climate
neither hot nor cold, but temperate; further, without marshes in
the neighbourhood. For when the morning breezes blow toward the
town at sunrise, if they bring with them mists from marshes and,
mingled with the mist, the poisonous breath of the creatures of the
marshes to be wafted into the bodies of the inhabitants, they will
make the site unhealthy. Again, if the town is on the coast with a
southern or western exposure, it will not be healthy, because in
summer the southern sky grows hot at sunrise and is fiery at noon,
while a western exposure grows warm after sunrise, is hot at noon,
and at evening all aglow.
2. These variations in heat and the subsequent cooling off
are harmful to the people living on such sites. The same conclusion
may be reached in the case of inanimate things. For instance,
nobody draws the light for covered wine rooms from the south or
west, but rather from the north, since that quarter is never
subject to change but is always constant and unshifting. So it is
with granaries: grain exposed to the sun's course soon loses its
good quality, and provisions and fruit, unless stored in a place
unexposed to the sun's course, do not keep long.
3. For heat is a universal solvent, melting out of things
their power of resistance, and sucking away and removing their
natural strength with its fiery exhalations so that they grow soft,
and hence weak, under its glow. We see this in the case of iron
which, however hard it may naturally be, yet when heated thoroughly
in a furnace fire can be easily worked into any kind of shape, and
still, if cooled while it is soft and white hot, it hardens again
with a mere dip into cold water and takes on its former
quality.
4. We may also recognize the truth of this from the fact that
in summer the heat makes everybody weak, not only in unhealthy but
even in healthy places, and that in winter even the most unhealthy
districts are much healthier because they are given a solidity by
the cooling off. Similarly, persons removed from cold countries to
hot cannot endure it but waste away; whereas those who pass from
hot places to the cold regions of the north, not only do not suffer
in health from the change of residence but even gain by
it.
5. It appears, then, that in founding towns we must beware of
districts from which hot winds can spread abroad over the
inhabitants. For while all bodies are composed of the four elements
(in Greek [Greek: stoicheia]), that is, of heat, moisture, the
earthy, and air, yet there are mixtures according to natural
temperament which make up the natures of all the different animals
of the world, each after its kind.
6. Therefore, if one of these elements, heat, becomes
predominant in any body whatsoever, it destroys and dissolves all
the others with its violence. This defect may be due to violent
heat from certain quarters of the sky, pouring into the open pores
in too great proportion to admit of a mixture suited to the natural
temperament of the body in question. Again, if too much moisture
enters the channels of a body, and thus introduces disproportion,
the other elements, adulterated by the liquid, are impaired, and
the virtues of the mixture dissolved. This defect, in turn, may
arise from the cooling properties of moist winds and breezes
blowing upon the body. In the same way, increase or diminution of
the proportion of air or of the earthy which is natural to the body
may enfeeble the other elements; the predominance of the earthy
being due to overmuch food, that of air to a heavy
atmosphere.
7. If one wishes a more accurate understanding of all this,
he need only consider and observe the natures of birds, fishes, and
land animals, and he will thus come to reflect upon distinctions of
temperament. One form of mixture is proper to birds, another to
fishes, and a far different form to land animals. Winged creatures
have less of the earthy, less moisture, heat in moderation, air in
large amount. Being made up, therefore, of the lighter elements,
they can more readily soar away into the air. Fish, with their
aquatic nature, being moderately supplied with heat and made up in
great part of air and the earthy, with as little of moisture as
possible, can more easily exist in moisture for the very reason
that they have less of it than of the other elements in their
bodies; and so, when they are drawn to land, they leave life and
water at the same moment. Similarly, the land animals, being
moderately supplied with the elements of air and heat, and having
less of the earthy and a great deal of moisture, cannot long
continue alive in the water, because their portion of moisture is
already abundant.
8. Therefore, if all this is as we have explained, our reason
showing us that the bodies of animals are made up of the elements,
and these bodies, as we believe, giving way and breaking up as a
result of excess or deficiency in this or that element, we cannot
but believe that we must take great care to select a very temperate
climate for the site of our city, since healthfulness is, as we
have said, the first requisite.
9. I cannot too strongly insist upon the need of a return to
the method of old times. Our ancestors, when about to build a town
or an army post, sacrificed some of the cattle that were wont to
feed on the site proposed and examined their livers. If the livers
of the first victims were dark-coloured or abnormal, they
sacrificed others, to see whether the fault was due to disease or
their food. They never began to build defensive works in a place
until after they had made many such trials and satisfied themselves
that good water and food had made the liver sound and firm. If they
continued to find it abnormal, they argued from this that the food
and water supply found in such a place would be just as unhealthy
for man, and so they moved away and changed to another
neighbourhood, healthfulness being their chief object.
10. That pasturage and food may indicate the healthful
qualities of a site is a fact which can be observed and
investigated in the case of certain pastures in Crete, on each side
of the river Pothereus, which separates the two Cretan states of
Gnosus and Gortyna. There are cattle at pasture on the right and
left banks of that river, but while the cattle that feed near
Gnosus have the usual spleen, those on the other side near Gortyna
have no perceptible spleen. On investigating the subject,
physicians discovered on this side a kind of herb which the cattle
chew and thus make their spleen small. The herb is therefore
gathered and used as a medicine for the cure of splenetic people.
The Cretans call it [Greek: hasplênon]. From food and water, then,
we may learn whether sites are naturally unhealthy or
healthy.
11. If the walled town is built among the marshes themselves,
provided they are by the sea, with a northern or north-eastern
exposure, and are above the level of the seashore, the site will be
reasonable enough. For ditches can be dug to let out the water to
the shore, and also in times of storms the sea swells and comes
backing up into the marshes, where its bitter blend prevents the
reproductions of the usual marsh creatures, while any that swim
down from the higher levels to the shore are killed at once by the
saltness to which they are unused. An instance of this may be found
in the Gallic marshes surrounding Altino, Ravenna, Aquileia, and
other towns in places of the kind, close by marshes. They are
marvellously healthy, for the reasons which I have
given.
12. But marshes that are stagnant and have no outlets either
by rivers or ditches, like the Pomptine marshes, merely putrefy as
they stand, emitting heavy, unhealthy vapours. A case of a town
built in such a spot was Old Salpia in Apulia, founded by Diomede
on his way back from Troy, or, according to some writers, by Elpias
of Rhodes. Year after year there was sickness, until finally the
suffering inhabitants came with a public petition to Marcus
Hostilius and got him to agree to seek and find them a proper place
to which to remove their city. Without delay he made the most
skilful investigations, and at once purchased an estate near the
sea in a healthy place, and asked the Senate and Roman people for
permission to remove the town. He constructed the walls and laid
out the house lots, granting one to each citizen for a mere trifle.
This done, he cut an opening from a lake into the sea, and thus
made of the lake a harbour for the town. The result is that now the
people of Salpia live on a healthy site and at a distance of only
four miles from the old town.
CHAPTER V
THE CITY WALLS
1. After insuring on these principles the healthfulness of
the future city, and selecting a neighbourhood that can supply
plenty of food stuffs to maintain the community, with good roads or
else convenient rivers or seaports affording easy means of
transport to the city, the next thing to do is to lay the
foundations for the towers and walls. Dig down to solid bottom, if
it can be found, and lay them therein, going as deep as the
magnitude of the proposed work seems to require. They should be
much thicker than the part of the walls that will appear above
ground, and their structure should be as solid as it can possibly
be laid.
2. The towers must be projected beyond the line of wall, so
that an enemy wishing to approach the wall to carry it by assault
may be exposed to the fire of missiles on his open flank from the
towers on his right and left. Special pains should be taken that
there be no easy avenue by which to storm the wall. The roads
should be encompassed at steep points, and planned so as to
approach the gates, not in a straight line, but from the right to
the left; for as a result of this, the right hand side of the
assailants, unprotected by their shields, will be next the wall.
Towns should be laid out not as an exact square nor with salient
angles, but in circular form, to give a view of the enemy from many
points. Defence is difficult where there are salient angles,
because the angle protects the enemy rather than the
inhabitants.
3. The thickness of the wall should, in my opinion, be such
that armed men meeting on top of it may pass one another without
interference. In the thickness there should be set a very close
succession of ties made of charred olive wood, binding the two
faces of the wall together like pins, to give it lasting endurance.
For that is a material which neither decay, nor the weather, nor
time can harm, but even though buried in the earth or set in the
water it keeps sound and useful forever. And so not only city walls
but substructures in general and all walls that require a thickness
like that of a city wall, will be long in falling to decay if tied
in this manner.
4. The towers should be set at intervals of not more than a
bowshot apart, so that in case of an assault upon any one of them,
the enemy may be repulsed with scorpiones and other means of
hurling missiles from the towers to the right and left. Opposite
the inner side of every tower the wall should be interrupted for a
space the width of the tower, and have only a wooden flooring
across, leading to the interior of the tower but not firmly nailed.
This is to be cut away by the defenders in case the enemy gets
possession of any portion of the wall; and if the work is quickly
done, the enemy will not be able to make his way to the other
towers and the rest of the wall unless he is ready to face a
fall.
5. The towers themselves must be either round or polygonal.
Square towers are sooner shattered by military engines, for the
battering rams pound their angles to pieces; but in the case of
round towers they can do no harm, being engaged, as it were, in
driving wedges to their centre. The system of fortification by wall
and towers may be made safest by the addition of earthen ramparts,
for neither rams, nor mining, nor other engineering devices can do
them any harm.
6. The rampart form of defence, however, is not required in
all places, but only where outside the wall there is high ground
from which an assault on the fortifications may be made over a
level space lying between. In places of this kind we must first
make very wide, deep ditches; next sink foundations for a wall in
the bed of the ditch and build them thick enough to support an
earth-work with ease.
7. Then within this substructure lay a second foundation, far
enough inside the first to leave ample room for cohorts in line of
battle to take position on the broad top of the rampart for its
defence. Having laid these two foundations at this distance from
one another, build cross walls between them, uniting the outer and
inner foundation, in a comb-like arrangement, set like the teeth of
a saw. With this form of construction, the enormous burden of earth
will be distributed into small bodies, and will not lie with all
its weight in one crushing mass so as to thrust out the
substructures.
8. With regard to the material of which the actual wall
should be constructed or finished, there can be no definite
prescription, because we cannot obtain in all places the supplies
that we desire. Dimension stone, flint, rubble, burnt or unburnt
brick,—use them as you find them. For it is not every neighbourhood
or particular locality that can have a wall built of burnt brick
like that at Babylon, where there was plenty of asphalt to take the
place of lime and sand, and yet possibly each may be provided with
materials of equal usefulness so that out of them a faultless wall
may be built to last forever.
CHAPTER VI
THE DIRECTIONS OF THE STREETS; WITH REMARKS ON THE
WINDS
1. The town being fortified, the next step is the
apportionment of house lots within the wall and the laying out of
streets and alleys with regard to climatic conditions. They will be
properly laid out if foresight is employed to exclude the winds
from the alleys. Cold winds are disagreeable, hot winds enervating,
moist winds unhealthy. We must, therefore, avoid mistakes in this
matter and beware of the common experience of many communities. For
example, Mytilene in the island of Lesbos is a town built with
magnificence and good taste, but its position shows a lack of
foresight. In that community when the wind is south, the people
fall ill; when it is northwest, it sets them coughing; with a north
wind they do indeed recover but cannot stand about in the alleys
and streets, owing to the severe cold.
2. Wind is a flowing wave of air, moving hither and thither
indefinitely. It is produced when heat meets moisture, the rush of
heat generating a mighty current of air. That this is the fact we
may learn from bronze eolipiles, and thus by means of a scientific
invention discover a divine truth lurking in the laws of the
heavens. Eolipiles are hollow bronze balls, with a very small
opening through which water is poured into them. Set before a fire,
not a breath issues from them before they get warm; but as soon as
they begin to boil, out comes a strong blast due to the fire. Thus
from this slight and very short experiment we may understand and
judge of the mighty and wonderful laws of the heavens and the
nature of winds.
3. By shutting out the winds from our dwellings, therefore,
we shall not only make the place healthful for people who are well,
but also in the case of diseases due perhaps to unfavourable
situations elsewhere, the patients, who in other healthy places
might be cured by a different form of treatment, will here be more
quickly cured by the mildness that comes from the shutting out of
the winds. The diseases which are hard to cure in neighbourhoods
such as those to which I have referred above are catarrh,
hoarseness, coughs, pleurisy, consumption, spitting of blood, and
all others that are cured not by lowering the system but by
building it up. They are hard to cure, first, because they are
originally due to chills; secondly, because the patient's system
being already exhausted by disease, the air there, which is in
constant agitation owing to winds and therefore deteriorated, takes
all the sap of life out of their diseased bodies and leaves them
more meagre every day. On the other hand, a mild, thick air,
without draughts and not constantly blowing back and forth, builds
up their frames by its unwavering steadiness, and so strengthens
and restores people who are afflicted with these
diseases.
4. Some have held that there are only four winds: Solanus
from due east; Auster from the south; Favonius from due west;
Septentrio from the north. But more careful investigators tell us
that there are eight. Chief among such was Andronicus of Cyrrhus
who in proof built the marble octagonal tower in Athens. On the
several sides of the octagon he executed reliefs representing the
several winds, each facing the point from which it blows; and on
top of the tower he set a conical shaped piece of marble and on
this a bronze Triton with a rod outstretched in its right hand. It
was so contrived as to go round with the wind, always stopping to
face the breeze and holding its rod as a pointer directly over the
representation of the wind that was blowing.
5. Thus Eurus is placed to the southeast between Solanus and
Auster: Africus to the southwest between Auster and Favonius;
Caurus, or, as many call it, Corus, between Favonius and
Septentrio; and Aquilo between Septentrio and Solanus. Such, then,
appears to have been his device, including the numbers and names of
the wind and indicating the directions from which particular winds
blow. These facts being thus determined, to find the directions and
quarters of the winds your method of procedure should be as
follows.
6. In the middle of the city place a marble amussium, laying
it true by the level, or else let the spot be made so true by means
of rule and level that no amussium is necessary. In the very centre
of that spot set up a bronze gnomon or "shadow tracker" (in Greek
[Greek: skiathêras]). At about the fifth hour in the morning, take
the end of the shadow cast by this gnomon, and mark it with a
point. Then, opening your compasses to this point which marks the
length of the gnomon's shadow, describe a circle from the centre.
In the afternoon watch the shadow of your gnomon as it lengthens,
and when it once more touches the circumference of this circle and
the shadow in the afternoon is equal in length to that of the
morning, mark it with a point.
7. From these two points describe with your compasses
intersecting arcs, and through their intersection and the centre
let a line be drawn to the circumference of the circle to give us
the quarters of south and north. Then, using a sixteenth part of
the entire circumference of the circle as a diameter, describe a
circle with its centre on the line to the south, at the point where
it crosses the circumference, and put points to the right and left
on the circumference on the south side, repeating the process on
the north side. From the four points thus obtained draw lines
intersecting the centre from one side of the circumference to the
other. Thus we shall have an eighth part of the circumference set
out for Auster and another for Septentrio. The rest of the entire
circumference is then to be divided into three equal parts on each
side, and thus we have designed a figure equally apportioned among
the eight winds. Then let the directions of your streets and alleys
be laid down on the lines of division between the quarters of two
winds.
8. On this principle of arrangement the disagreeable force of
the winds will be shut out from dwellings and lines of houses. For
if the streets run full in the face of the winds, their constant
blasts rushing in from the open country, and then confined by
narrow alleys, will sweep through them with great violence. The
lines of houses must therefore be directed away from the quarters
from which the winds blow, so that as they come in they may strike
against the angles of the blocks and their force thus be broken and
dispersed.
9. Those who know names for very many winds will perhaps be
surprised at our setting forth that there are only eight.
Remembering, however, that Eratosthenes of Cyrene, employing
mathematical theories and geometrical methods, discovered from the
course of the sun, the shadows cast by an equinoctial gnomon, and
the inclination of the heaven that the circumference of the earth
is two hundred and fifty-two thousand stadia, that is, thirty-one
one million five hundred thousand paces, and observing that an
eighth part of this, occupied by a wind, is three million nine
hundred and thirty-seven thousand five hundred paces, they should
not be surprised to find that a single wind, ranging over so wide a
field, is subject to shifts this way and that, leading to a variety
of breezes.
10. So we often have Leuconotus and Altanus blowing
respectively to the right and left of Auster; Libonotus and
Subvesperus to the right and left of Africus; Argestes, and at
certain periods the Etesiae, on either side of Favonius; Circias
and Corus on the sides of Caurus; Thracias and Gallicus on either
side of Septentrio; Supernas and Caecias to the right and left of
Aquilo; Carbas, and at a certain period the Ornithiae, on either
side of Solanus; while Eurocircias and Volturnus blow on the flanks
of Eurus which is between them. There are also many other names for
winds derived from localities or from the squalls which sweep from
rivers or down mountains.
12. If he was wrong, the only result will be that the
individual winds may blow, not with the scope expected from his
measurement, but with powers either more or less widely extended.
For the readier understanding of these topics, since I have treated
them with brevity, it has seemed best to me to give two figures,
or, as the Greeks say, [Greek: schêmata], at the end of this book:
one designed to show the precise quarters from which the winds
arise; the other, how by turning the directions of the rows of
houses and the streets away from their full force, we may avoid
unhealthy blasts. Let A be the centre of a plane surface, and B the
point to which the shadow of the gnomon reaches in the morning.
Taking A as the centre, open the compasses to the point B, which
marks the shadow, and describe a circle. Put the gnomon back where
it was before and wait for the shadow to lessen and grow again
until in the afternoon it is equal to its length in the morning,
touching the circumference at the point C. Then from the points B
and C describe with the compasses two arcs intersecting at D. Next
draw a line from the point of intersection D through the centre of
the circle to the circumference and call it E F. This line will
show where the south and north lie.