ROMAN CAMPS AND STATIONS. 245 



pose that for retaining and defending with fewer troops the coun- 

 try which had been long before conquered by large armies, many 

 detached posts might be occupied by small bodies of men, and 

 that these forts might be often chosen so as to be guarded as 

 much by difficult ground as by artificial works. And this agrees 

 with what is said by Vegetius (De Re Militari, i. 23) writing in 

 the days of Valentinian (A.D. 385), that Roman camps were 

 made square, round, or triangular, to suit the nature of the 

 ground, the most approved form being the oblong, with the 

 length one-third greater than the breadth*. 



It may be doubted, therefore, whether even such posts as 

 those at Langton and Hutton Ambo can be proved to be of 

 British work, by the irregularity of their figure. In the latter 

 case, however, the inequality of the height of the bank, and its 

 rising into tumulary mounds as at Arbelow, increase the pro- 

 bability, and in the former we may appeal with some confidence 

 to the proximity of the ' double dikes/ 



The essential parts of the defence are always the external 

 ditch and the internal rampart or wall. The Greek wall (-m^o?) 

 which stood ' while Hector and Achilles raged/ was flanked 

 by lofty towers (irvpyot,) furnished with a pair of gates (TrvXai), 

 and surrounded by a deep, broad and great palisaded ditch 

 (ra<f)pov), II. vii. 436. It was constructed near the great tumulus 

 raised over the slain (ib. 435). The gates being burst open, the 

 entrance was unimpeded. 



The Roman temporary camp has only one such ditch (fossa) 

 and one bank (vallum, agger) ; but the permanent station at 

 Cawthorne has two fossa? and two aggera, across which the road 

 entrance is level. For camps, whether intended to hold a cohort 

 or a legion, four gates are usually assigned : greater camps of 

 the age of Agricola have six gates ; there are camps with a still 

 greater number of gates, but their age is not certain (Rey 

 Cross, p. 18, and Kirby Thure). Small posts have sometimes 

 only one opening (Roy, pi. 31). 



* Diet, of Gr. and Rom. Antiq. p. 205. 



