1Mountains; others damp and waſhy, as are
thoſe which lie near Seas or Lakes, or in Bot
toms between Hills. Others are ſo ſituated as
to be neither always dry nor always wet, which
is the Nature of caſy Aſcents, where the
Water does not lie and ſoak, but runs gently
off. We muſt never truſt too haſtily to any
Ground, tho' it does reſiſt the Pick-axe, for
it may be in a Plain, and be infirm, the Con
ſequence of which might be the Ruin of the
whole Work. I have ſeen a Tower at Meſtri,
a Place belonging to the Venetians, which in
a few Years after it was built, made its Way
thro' the Ground it ſtood upon, which, as
the Fact evinced, was a looſe weak Soil, and
bury'd itſelf in Earth, up to the very Battle
ments. For this Reaſon they are very much
to be blamed, who not being provided by Na
ture with a Soil fit to ſupport the Weight of
an Edifice, and Lightning upon the Ruins or
Remains of ſome old Structure, do not take
the Pains to examine the Goodneſs of its Foun
dation, but inconſiderately raiſe great Piles of
Building upon it, and out of the Avarice of
ſaving a little Expence, throw away all the
Money they lay out in the Work. It is there
fore excellent Advice, the firſt Thing you do
to dig Wells, for ſeveral Reaſons, and eſpeci
ally in order to get acquainted with the Strata
of the Earth, whether ſound enough to bear
the Superſtructure, or likely to give way. Add,
likewiſe, that the Water you find in them, and
the Stuff you dig out, will be of great Service
to you in ſeveral Parts of your Work; and
moreover, that the Opening ſuch Vents will be
a great Security to the Firmneſs of the Build
ing, and prevent its being injured by ſubter
rancous Exhalations. Having therefore, either
by digging a Well, or a Ciſtern, or a Shoar, or
any other Hole of that Nature, made yourſelf
thoroughly acquainted with the Veins or
Layers of the Earth, you are to make Choice
of that which you may moſt ſafely truſt with
your Superſtructure. In Eminences, or where
ever elſe the Water is running down waſhes
away the Ground, the deeper you make your
Trench, the better. And that the Hills are
actually eaten and waſh'd away, and waſted
more and more daily by continual Rains, is
evident ſrom the Caverns and Rocks which
every Day grow more viſible, whereas at firſt
they were ſo cover'd with Earth that we could
hardly perceive them. Mount Morello, which
is about Florence, in the Days of our Fathers
was all over cover'd with Firs; and now it is
quite wild and naked; occaſion'd, as I ſup
poſe, by the Waſhing of the Rain In Situ
ations upon Slopes, Columella directs us to be
gin our Foundations at the loweſt Part of the
Slope firſt; which is certainly very right, for
beſides that whatever you lay there will always
ſtand firm and unmoveable in its Place, it will
alſo ſerve as a Prop or Buttreſs, to whatever
you add to the upper Parts, if you aftewards
think fit to enlarge your Structure. You will
alſo thereby diſcover and provide againſt thoſe
Defects which ſometimes happen in ſuch Tren
ches by the cracking or falling in of the Earth. In
marſhy Grounds, you ſhould make your Trench
very wide, and fortify both Sides of it with
Stakes, Hurdles, Planks, Sea-weeds, and Clay,
ſo ſtrongly that no Water may get in; then
you muſt draw off every drop of Water that
happens to be left within your Frame-work,
and dig out the Sand, and clear away the Mud
from the Bottom till you have firm dry Ground
to ſet your Foot upon. The ſame you are to
do in ſandy Ground, as far as Neceſſity requires.
Moreover, the Bottom of the Trench
muſt be laid exactly level, not ſloping on
either Side, that the Materials laid upon it may
be equally balanced. There is a natural in
ſtinct in all heavy Bodies to lean and preſs
upon the loweſt Parts. There are other
Things which they direct us to do in marſhy
Situations, but they belong rather to the Wal
ling than to the Foundations. They order us to
drive into the Ground a great Number of
Stakes and Piles burnt at the End, and ſet
with their Heads downwards, ſo as to have
a Surface of twice the Breadth that we intend
for our Wall; that theſe Piles ſhould never be
leſs in length than the eighth Part of the
Heighth of the Wall to be built upon them,
and for their Thickneſs, it ſhould be the
twelſth Part of their Length, and no leſs. Laſtly
they ſhould be drove in ſo cloſe that their is
not room for one more. The Inſtrument we
uſe for driving in theſe Piles, whatever Sort it
it is of, ſhould do its Buſineſs by a great many
repeated Strokes; for when it is too heavy,
coming down with an immenſe and intolerable
Force, it breaks and ſplits the Timber; but the
continual Repetition of gentle Strokes wearies
and overcomes the greateſt Hardneſs and Obſti
nacy of the Ground. You have an Inſtance of this
when you go to drive a ſmall Nail into a hard
Piece of Timber; if you uſe a great heavy
Hammer, it won't do; but if you work with
a manageable light one, it penetrates imme-
thoſe which lie near Seas or Lakes, or in Bot
toms between Hills. Others are ſo ſituated as
to be neither always dry nor always wet, which
is the Nature of caſy Aſcents, where the
Water does not lie and ſoak, but runs gently
off. We muſt never truſt too haſtily to any
Ground, tho' it does reſiſt the Pick-axe, for
it may be in a Plain, and be infirm, the Con
ſequence of which might be the Ruin of the
whole Work. I have ſeen a Tower at Meſtri,
a Place belonging to the Venetians, which in
a few Years after it was built, made its Way
thro' the Ground it ſtood upon, which, as
the Fact evinced, was a looſe weak Soil, and
bury'd itſelf in Earth, up to the very Battle
ments. For this Reaſon they are very much
to be blamed, who not being provided by Na
ture with a Soil fit to ſupport the Weight of
an Edifice, and Lightning upon the Ruins or
Remains of ſome old Structure, do not take
the Pains to examine the Goodneſs of its Foun
dation, but inconſiderately raiſe great Piles of
Building upon it, and out of the Avarice of
ſaving a little Expence, throw away all the
Money they lay out in the Work. It is there
fore excellent Advice, the firſt Thing you do
to dig Wells, for ſeveral Reaſons, and eſpeci
ally in order to get acquainted with the Strata
of the Earth, whether ſound enough to bear
the Superſtructure, or likely to give way. Add,
likewiſe, that the Water you find in them, and
the Stuff you dig out, will be of great Service
to you in ſeveral Parts of your Work; and
moreover, that the Opening ſuch Vents will be
a great Security to the Firmneſs of the Build
ing, and prevent its being injured by ſubter
rancous Exhalations. Having therefore, either
by digging a Well, or a Ciſtern, or a Shoar, or
any other Hole of that Nature, made yourſelf
thoroughly acquainted with the Veins or
Layers of the Earth, you are to make Choice
of that which you may moſt ſafely truſt with
your Superſtructure. In Eminences, or where
ever elſe the Water is running down waſhes
away the Ground, the deeper you make your
Trench, the better. And that the Hills are
actually eaten and waſh'd away, and waſted
more and more daily by continual Rains, is
evident ſrom the Caverns and Rocks which
every Day grow more viſible, whereas at firſt
they were ſo cover'd with Earth that we could
hardly perceive them. Mount Morello, which
is about Florence, in the Days of our Fathers
was all over cover'd with Firs; and now it is
quite wild and naked; occaſion'd, as I ſup
poſe, by the Waſhing of the Rain In Situ
ations upon Slopes, Columella directs us to be
gin our Foundations at the loweſt Part of the
Slope firſt; which is certainly very right, for
beſides that whatever you lay there will always
ſtand firm and unmoveable in its Place, it will
alſo ſerve as a Prop or Buttreſs, to whatever
you add to the upper Parts, if you aftewards
think fit to enlarge your Structure. You will
alſo thereby diſcover and provide againſt thoſe
Defects which ſometimes happen in ſuch Tren
ches by the cracking or falling in of the Earth. In
marſhy Grounds, you ſhould make your Trench
very wide, and fortify both Sides of it with
Stakes, Hurdles, Planks, Sea-weeds, and Clay,
ſo ſtrongly that no Water may get in; then
you muſt draw off every drop of Water that
happens to be left within your Frame-work,
and dig out the Sand, and clear away the Mud
from the Bottom till you have firm dry Ground
to ſet your Foot upon. The ſame you are to
do in ſandy Ground, as far as Neceſſity requires.
Moreover, the Bottom of the Trench
muſt be laid exactly level, not ſloping on
either Side, that the Materials laid upon it may
be equally balanced. There is a natural in
ſtinct in all heavy Bodies to lean and preſs
upon the loweſt Parts. There are other
Things which they direct us to do in marſhy
Situations, but they belong rather to the Wal
ling than to the Foundations. They order us to
drive into the Ground a great Number of
Stakes and Piles burnt at the End, and ſet
with their Heads downwards, ſo as to have
a Surface of twice the Breadth that we intend
for our Wall; that theſe Piles ſhould never be
leſs in length than the eighth Part of the
Heighth of the Wall to be built upon them,
and for their Thickneſs, it ſhould be the
twelſth Part of their Length, and no leſs. Laſtly
they ſhould be drove in ſo cloſe that their is
not room for one more. The Inſtrument we
uſe for driving in theſe Piles, whatever Sort it
it is of, ſhould do its Buſineſs by a great many
repeated Strokes; for when it is too heavy,
coming down with an immenſe and intolerable
Force, it breaks and ſplits the Timber; but the
continual Repetition of gentle Strokes wearies
and overcomes the greateſt Hardneſs and Obſti
nacy of the Ground. You have an Inſtance of this
when you go to drive a ſmall Nail into a hard
Piece of Timber; if you uſe a great heavy
Hammer, it won't do; but if you work with
a manageable light one, it penetrates imme-
zoom in
zoom out
zoom area
full page
page width
set mark
remove mark
get reference
digilib