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JOURNEY FROM 
We may observe with regard to the structure of these forts, that 
some of them have the habitable part of the building (which is 
always of a quadrangular form, and placed in the centre) surrounded 
by a double wall of very solid work ; leaving a space between the 
walls, of ten, twenty, and thirty feet, sometimes of more, in which 
wells are occasionally found, and which may have served for the 
accommodation of the horses, sheep, or cattle of the garrison. 
Others have been built in one sohd mass, with sloping sides, resem- 
bling the base of a pyramid, having only a square space left in the 
centre for the accommodation of the troops and the stowage of 
stores and provision. On these there is always a platform, and 
sometimes two, the sides of which form a glacis at a slope of from 
thirty to forty-five degrees, some of them being steeper than others : 
it seems probable that a parapet originally existed on the platforms 
of some of the forts, behind which the troops might more securely 
encounter their enemies ; but on most of them there are now no 
traces of any defence of this nature, and the platform is left exposed. 
The lower platform is usually raised about ten and fifteen feet from 
the ground, and the upper one about eight or twelve feet above that. 
Trenches are rarely seen round the last mentioned buildings, but 
those enclosed within walls usually possessed that additional defence. 
Both are constructed with stone found in the neighbourhood, gene- 
rally without any cement, particularly the sloping ones, although a 
very good cement may sometimes be observed in them : the most 
considerable forts are built with large and regularly-shaped stones, 
while the more unimportant are composed of stones of unequal forms 
