He was first buried in the Alter St.-Matthäus-Kirchhof in Schöneberg, but then his remains were transferred to a newly built family mausoleum in Stahnsdorf South-Western Cemetery in 1935.

Together with Charles Toussaint Langenscheidt developed a self-learning method, which he published in 1856 under the title Unterrichtsbriefe zur Erlernung der französischen Sprache ("Teaching letters for learning the French language").

In 1861, together with Carl Dalen and Henry Lloyd, Langenscheidt published "English lessons letters" (similar in structure to the French).

From 1869 Langenscheidt worked with Karl Sachs and Césaire Villatte on the Encyklopädisches französisch-deutsches und deutsch-französisches Wörterbuch ("Encyclopedic French–German and German–French dictionary") and was finally able to publish it in 1880.

In 1891, in close collaboration with Eduard Muret and Daniel Sanders, he started working on the English equivalent, the Encyklopädisches englisch-deutsches und deutsch-englisches Wörterbuch ("Encyclopedic English–German and German–English dictionary").