The investigations made by Dr Walter Lehmann in Central America (1907-1909), prove that these Mexican elements were extended through Guatemala, Salvador, a small part of Nicaragua (the territory of the Nicaraos) and on several places in the peninsula of Nicoya (Costa Rica) amongst the autochthonous Chorotega or Mangue.
The barbarians belonged to the great family of the SumoMisquito Indians, the civilized race was that of the Chorotega or Mangue (Dirian, Orotinan, &c.).
The Chorotega or Mangue language, so closely affiliated to the Chiapanec, is now extinct, but its former extension is to be recognized by many Indian local names.
Another improvement was the completion and embellishment of the Mangue canal, originally designed as an entrance to a central market for the boats plying on the bay, but now destined for drainage purposes and as a public pleasure ground.
In the work of improving the city, the national government assumed the expense of the commercial quays, the filling of the Sao Christovao bay, the opening of the Mangue canal and its embellishment, the opening of the Avenida Central, the extension of the sewage system and the addition of new sources to the water supply, while the city was responsible for the Avenida Beira-Mar, the opening of a new avenue from the Largo da Lapa westward to Rua Frei Caneca, the removal of the Morro do Senado, the widening of some streets crossing the Avenida Central and the opening and straightening of other streets.