(508 FORT! F 
fhod with iron in the water before the fort ; or by fixing 
along the battery a kind of fhed made with planks that 
are mufket-proof, and covered with raw hides or earth, 
that they may not be let on fire by combuftibles thrown 
from the fhips. 
When a harbour, being a bay, has a flioal or fmall 
ifland lying before its entrance, it may be fortified by 
building a thong fort on the ifland, in a place where it 
can command the entrance on both fides, where the fize 
of the ifland is not too large for this purpofe ; but when 
the mouth of the harbour, and the extent of the ifland, 
are fuch that one fort cannot guard the entrance, then two 
or more forts fhould be raifed in the moft commodious 
fituations to command the avenues to the bay. Arid be- 
fides the forts raifed on fuch an ifland or flioal, there 
fhould be others raifed on the mod: convenient points of 
land forming the mouth of the bay ; which will render 
the defence of the paflage more fecure ; as is the cafe 
with the blockhoufe or battery eredted oppofite the Point 
at the entrance into Portfmouth harbour ; of Brownfea 
cafile, at the entrance by the Needles near the weftern ex- 
fremity of the Ifle of Wight. 
As there may be feveral fpots or points proper to ereft 
fuch defences upon, and which may command the entrance 
of the harbour in the manner deferibed above, yet it is 
of importance to know which will have the moft advan¬ 
tages, and feweft difadvantages; for both circumftances 
are to be duly contemplated, and that chofen which lias 
mod: of the former, and feweft of the latter. Thus the 
foil fhould be the firmed, and the ground of a height 
fufficient to be out of the reach of tides and floods, and 
not much higher than is barely neceflary to avoid thofe 
■inconveniences ; for the cannon are more readily brought 
to point-blank (hot, and thus infure deciflve execution, 
when near the water’s level. The place fhould be diffi¬ 
cult for an enemy to land in its neighbourhood ; and if 
landed, where they may be moft impeded in their march 
to the fort—where fuccours may eafily approach—where 
the troops on duty may without much trouble obtain the 
necelfaries of life—and where there are the feweft noxious 
exhalations, to render it unhealthy within. 
It may frequently happen, that in fuch fituations the 
paffiige between the ifland and main is rather too wide 
for cannon to command acrofs; therefore, if the place is 
of fufficient importance, there may be many ways con¬ 
trived to remedy this defect, when it is poffible to be 
avoided. The beft are thofe which oblige (hipping to 
keep in one regular tra£t or channel ; and when this can 
i>e accompliflied, either by finking old (hipping, running 
out moles, or contriving to form land-banks or flioals, or 
by any other means that the fituation of the place can fur- 
nifit, it fhould always be done. Forts alfo or batteries 
may be advanced fo far into the water, as to command 
the channel ; as is the cafe, at high water, with Calfliot 
caftle, at the entrance of the Southampton water, on the 
eaftern extremity of the New Foreft. But where the 
paffiage cannot be reduced to lefsthan two channels, then 
a fort fhould be eredted, if poffible, between them. 
When the harbour is in a bay, and the points which 
form the entrance ftretch into the fea, and approach one 
another within cannon-(hot, it fhould be fortified by 
building on both (ides of its entrance one or more forts ; 
and if it is poffible, a fort fhould alfo be built within the 
harbour’s mouth, in fuch a (ituation, that its cannon can 
rake the (hipping fore and aft as they come in ; and this 
would be a noble referve, fhould an enemy’s fleet force 
their way between the forts which command the entrance. 
If there is no proper fpot for f'ucli a fort, let others be 
erected on the moft convenient points, that command the 
turning to the right and left within the month of the 
bay ; for by tliefe meafures an enemy will be obliged to 
endure a running fire, which, if the forts be well con- 
ftiudted, be will fcarcely be able to fuftain. 
When a harbour is formed by a duller of iflands, it is 
eafily fortified, particularly when the channel between 
I C A T I O N. 
the iflands is not-too wide for the command of cannon 
from one or both fhores, the directions how to place the 
forts in the foregoing cafes being alike applicable to this. 
And in places where the channel is more than cannon-fhot 
from either fliore, the (hipping that can ride there muft 
depend upon the batteriesafhore, as in the firft cafe, when 
the fliore is bold enough for the (hips to run under the 
cannon. 
When the harbour lies in an inlet or river fome miles 
above its mouth, and the paffage to the port lies ftraight, 
and can be commanded from tide to fide, a fort built at 
each point of the entrance, and two others between them 
and the harbour, but not oppofite to one another, unlefs 
the width of the channel requires it, will, in moft cafes, 
be a proper fecurity to the (hipping in fuch a harbour. 
When the channel or river is winding, the forts fhould be 
built where they can command a reach at leaft ; or be fo 
placed at the bends, as to command two adjacent reaches ; 
for as vefiels muft tack near the forts fo placed, they will 
at thofe times be more under the command of the bat¬ 
teries, than they would be when palling them on a diredt 
courfe. 
It is not always neceflary, or even convenient, to make 
tliefe forts on figures perfedtly regular; for the fituation 
may require fome of its fides to be fliorter than others : 
neither is it neceflary that the figures fhould be fortified 
with baftions, or half-bafiions, at the angles; for there 
are many cafes, in which it will anfwer the purpofe 
equally well, or even better, to make a baftion on the fide 
of a figure toward the middle; but then the faces of the 
baftion fhould be fo conftrudied, that they may be raked 
from the extremities of that fide, by a defence of at leaft 
ten or twelve yards. 
If the place on which the fort is to be built is furround- 
ed with water, forming a channel on both fides, the figure 
is to be difpofed fo as to have one or two of its fronts 
turned toward each channel, by which means the batteries 
in the flanks will fcour both up and down the ftream, 
while thofe in the faces and curtains command the paf¬ 
fage diredtly before them. That part to feaward may 
either have a front extended along it, or have one of the 
points of the figure directed that way, according as it may 
be judged moft convenient: and if before tliefe fronts 
there be any place at which an enemy can land, then one 
or more batteries fhould be fo formed, that their guns 
may be brought to bear on fuch landing place; and if 
this be not fufficient, a fmall outwork fhould be built 
near the fpot, to make the landing more difficult and dan¬ 
gerous ; and on this account the fort fhould be furtfifhed 
with a ditch, covered-way, and glacis ; but the part next 
the harbour will be fufficiently lecured by a line thrown 
up, and properly flanked. Should the fituation be on a 
rock, where there is no danger of an enemy’s landing, a 
ftrong line, capable of covering the troops and cannon, 
w ill luffice. If there be only a channel on one fide fit for 
(hipping to pafs through, that fide fhould be fortified as 
in the former cafe ; and left the enemy’s boats fhould get 
through on the oppofite fide, it fhould alfo be put in a 
(late of defence : but here a (light redan, furnifhed with 
a few pieces of fmall cannon, may be found a fufficient 
defence. 
When a fort is built on a point of the main, the kind of 
difpofition ufed in the foregoing cafe, next to the chan¬ 
nel, will alfo obtain in this: but it is neceflary to take 
proper care of the land fide, which in this cafe is more 
liable to be attacked than in the former. In the fortify¬ 
ing of the land fide, the works lliould be proportioned to 
the ftrength of the enemy that may probably appear be¬ 
fore it. For there are many places where there is no like¬ 
lihood of ever feeing an enemy with a (Ironger force than 
can be exerted by a fleet of three or four (hips of war; 
and as thefe cannot be furniftied fufficiently for under¬ 
taking a regular land-fiege, a well-flanked line, with a 
ditch, if properly defended, will fecure the place againft 
the attacks of Tailors or marines unprovided with artil- 
