FORTIFICATION. 
stances, where A must he completely 
screened from the exterior, be proper to 
sink the terre-pleine of B so very low, that 
its cannon may just graze the terre-pleine 
of the raveline, C ; making the parapet of a 
due height, and forming a substantial shed 
of three inch boards, &c. nearly flat, over 
the banquette, at a foot above the crest of 
the parapet. This prevents the enemy from 
commanding the terre-pleine of the redoubt, 
while, at the same time, those defending it, 
would do ample execution through the nar- 
row slit, or opening, between the crest and 
the shed. The latter would effectually 
keep off grenades, &c. and give the defend- 
ers great confidence. The dotted lines 
above the rampart, A, shew the height to 
which its parapet would necessarily be 
raised, if B were elevated even afoot and a 
half only above C. The dotted line from 
C towards B, shews the level to which 
the genouliere, or crest of the lower slope 
of tiie embrasure, may be brought, so as to 
allow the fire from B to graze the terre- 
pleine of C, and to drive the enemy from 
the raveline. 
Relinquishing the explanation of what 
relates to the more scientific parts of the 
topic, we must now enter upon the descrip- 
tion of many other matters, indispensably 
necessary on this occasion. We have al- 
ready spoken of bomb-proofs. These are 
vaulted chambers, either running under long 
arches, or groined, and standing on substan- 
tial walls and pillars. The term very pro- 
perly implies, that the arches should be suffi- 
ciently strong to resist the fall of shells, or, 
at least, to prevent their penetrating into 
the chambers. It generally demands, at 
least, a yard in thickness to produce such a 
firm resistance ; the masonry should be of 
the very best materials, and put together in 
a workmanlike manner. The casemates, 
thus arched over, should be further covered 
with three or four feet of soil, where such 
an addition would not raise the terre-pleine 
too high ; for, by allowing a shell to bury 
itself completely, its splinters do not occa- 
sion half so much mischief, as when the 
explosion is more superficial ; although a 
quantity of soil may be thrown out. Per- 
haps the best contrivance for small case- 
mates, defended by breast-works, is the 
giving them such a slope, as may cause 
Shells to fall into pits, &c. so as to do no 
damage. Such pits answer well in the cen- 
tres of round or polygon redoubts, where 
only a parapet is left around the top, and 
might, perhaps, be advantageously made in 
the centre of block-houses, &c. 
In the formation of magazines, for ammu- 
nition, the arches are usually made double* 
that is, one greater arch covers two smaller 
ones ; the latter resting on a central pier* 
as seen in fig. 5. In this case every arch 
should be bomb proof, and the roof should 
be pitched ; the end falling off by a gradu- 
ally rounding, and the whole well supported 
by buttresses. The walls of magazines are 
generally double ; the buttresses are some- 
times pierced at their sides with small loop- 
holes for the admission of air and of light to 
the surrounding passage. All the fastenings 
should be of brass or of copper, and no 
wood or iron allowed in any part what- 
ever. 
The ramparts are ascended by means of 
long slopes, called ramps, laying in general 
parallel with, and leaning against them; 
these ought always to be broad enough to 
admit a gun passing up and down, mounted 
on its carriage. The ramps into solid bas- 
tions sometimes diverge into three branches* 
of which two lay along the insides of the 
adjoining curtains, while the third runs 
straight up in a line with the capital, i. e. 
w ith the centre of the gorge, pointing to- 
wards the saliant angle. Thus H C is the 
capital of the bastion 4, fig. 1. Horse- 
shoe cavaliers have usually but one ramp, 
placed in the centre of the rear, as shewn 
by the two parallel lines proceeding from 
that in the bastion, C, of the crown work, 
M, fig. 1. 
The proper arrangement of streets, with- 
in fortified towns, is of the utmost im- 
portance, by contributing essentially to the 
ready resort of troops to their posts, and 
facilitating the supply of stores. Every 
avenue ought to have a barrier, both to keep 
the inhabitants under proper controul, and 
to prevent the effects of various stratagems 
in behalf of a surprise. Those houses which 
command the interior of the works should 
be always reserved for the habitations of the 
garrison, and should likewise be supplied 
with small quantities of ammunition. The 
arsenals should be completely covered from 
the fire of the enemy’s batteries ; and, toge- 
ther with every building appropriated to 
the lodgment of troops, or of stores, &c. 
should be covered in with bomb proofs. 
The magazines should not be too large, but 
commodiously situated for the distribution 
of ammunition, and every precaution should 
be taken to keep all combustible stores, as 
