LEA (THE), a river of Beds, Herts, Essex, and Middlesex. It rises in Beds, near Houghton-Regis; runs south-eastward, past Luton, into Herts; goes across that county, windingly, but chiefly in an easterly direction, past Wheathampstead, Hatfield, Hertford, and Ware, to the neighbourhood of Hoddesdon; runs thence southward, on the boundary between Essex on the left and Herts and Middlesex on the right, past Waltham-Abbey, Chingford, and Stratford; and falls into the Thames a little below Blackwall. Its length of course is about 46 miles; and its chief tributary is the Stort. It was known to the ancient Britons as Logodunum or Logrodunum; and it gave the name of Leamouth or Leymouth to the place at its embouchure now called Limehouse. The navigation of its lower reaches was a subject of litigation, in the time of Henry V., between the Corporation of London and the Abbot of Waltham; it was regulated or protected and improved, by various charters in succeeding reigns; and it underwent special improvement, by embankments and by the construction of locks, under an act of parliament passed in 1855.

(John Marius Wilson, Imperial Gazetteer of England and Wales (1870-72))