B. 4.--Amid all these snares the most certain identification of a Roman site is furnished by the discovery of inscriptions relating to the special troops with which the name is associated in historical documents. When, for example, we find in the Roman station at Birdoswald, on the Wall of Hadrian, an inscription recording the occupation of the spot by a Dacian cohort, and read in the 'Notitia' that such a cohort was posted at _Amboglanna per lineam Valli_, we are sure that Amboglanna and Birdoswald are identical. This method, unfortunately, helps us very little except on the Wall, for the legionary inscriptions elsewhere are found in many places with which history does not particularly associate the individual legions thus commemorated.[204] However, the special number of such traces of the Second Legion at Caerleon, the Twentieth at Chester, and the Sixth at York, would alone justify us in certainly determining those places to be the Isca, Deva, and Eboracum given as their respective head-quarters in our documentary and historical evidence. B. 5.--In the case of York another proof is available; for the name, different as it sounds, can be traced, by a continuous stream of linguistic development, through the Old English Eorfowic to the Roman _Eboracum_. In the same way the name of _Dubris_ has unmistakably survived in Dover, _Lemannae_ in Lympne, _Regulbium_ in Reculver. _Colonia, Glevum_, _Venta, Corinium, Danum_, and _Mancunium_, with the suffix "chester,"[205] have become Colchester, Gloucester, Winchester, Cirencester, Doncaster, and Manchester. Lincoln is _Lindum Colonia_, Richborough, _Ritupis_; while the phonetic value of the word London has remained absolutely unaltered from the very first, and varies but slightly even in its historical orthography. B. 6.--With names of this class, of which there are about thirty, for a starting-point, we can next, by the aid of our various lists (especially Ptolemy's, which gives the tribe in which each town lies, and the 'Itinerary'), assign, with a very high degree of probability, some thirty more--similarity of name being still more or less of a guide. For example, when midway between _Venta_ (Winchester) and _Sorbiodunum_ (Sarum) the 'Itinerary' places _Brige_, and the name _Broughton_ now occupies this midway spot, _Brige_ and _Broughton_ may be safely assumed to be the same. This method shows Leicester to be the Roman _Ratae_, Carlisle to be _Luguvallum_, Newcastle _Pons Aelii_, etc., with so much probability that none of these identifications have been seriously disputed amongst antiquaries; while few are found to deny that Cambridge represents _Camboricum_,[206] Huntingdon (or Godmanchester) _Durolipons_, Silchester _Calleva_, etc. A list of all the sites which may be said to be fairly certified will be found at the end of this chapter.