A list of Roman officials, civil and military, throughout the empire has come down to us; in this list—­Notitia Dignitatem et Administratem, tam civilium quam militarium in partibus orientis et occidentis—­the portion which relates to the Wall is headed, Item per lineam Valli—­“Also along the line of the Wall.”  The following is a copy of this portion, as given by Dr. Bruce in his Handbook to the Roman Wall.

  The Tribune of the fourth cohort of the Lingones at Segedunum.

  The Tribune of the first cohort of Cornovii at Pons Aelii.

  The Prefect of the first ala of the Asturians at Condercum.  The
  Tribune of the first cohort of the Frixagi (Frisii) at Vindobala.

  The Prefect of the Savinian ala at Hunnum.

  The Prefect of the second ala of the Asturians at Cilurnum.

  The Tribune of the first cohort of the Batavians at Procolitia.

  The Tribune of the first cohort of the Tungrians at Borcovicus.

  The Tribune of the fourth cohort of the Gauls at Vindolana.

  The Tribune of the first cohort of Asturians at Aesica.

  The Tribune of the second cohort of Dalmatians at Magna.

  The Tribune of the first cohort of Dacians, styled Aelia, at Amboglanna.

  The Prefect of the ala called “Petriana,” at Petriana.

  The Prefect of a detachment of Moors, styled Aureliani, at Aballaba.

  The Tribune of the second cohort of the Lingones at Congavata.

  The Tribune of the first cohort of Spaniards at Axelodunum.

  The Tribune of the second cohort of the Thracians at Gabrosentum.

  The Tribune of the first marine cohort, styled Aelia, at Tunnocelum.

  The Tribune of the first cohort of the Morini at Glannibanta.

  The Tribune of the third cohort of the Nervians at Alionis.

  The Cuneus of men in armour at Bremetenracum.

  The Prefect of the first ala, styled Herculean, at Olenacum.

  The Tribune of the sixth cohort of the Nervians at Virosidum.

Of these stations, with their officers and troops, only those as far as Magna are in Northumberland; the rest continue the chain of defences across Cumberland to the Solway Firth.  Besides these stations, there were castella at the distance of every Roman mile (seven furlongs) along the Wall, from which circumstance they are known as “mile-castles.”  They provided accommodation for the troops necessary between the stations, which were at some distance from each other; and between each two castella there were also erected two turrets, so that communication from one end of the Wall to the other was speedy and certain.