The Gaps

 We know that at the end of October 1919 Landín tendered his resignation by telegram: "Circunstancias especiales que por correo explico, obliguanme suplicar a esta superioridad respetuosamente acepte mi renuncia como agente Consular en Columbus, NM." 

But what were the circunstancias especiales that forced him to leave? We don't have the letter he promised to send. At least, I haven't found it yet. 

Consular officials accepted his resignation and appointed him as a Consul in San Salvador. His superiors reported that his post in Columbus officially ended 23 January 1920, “por habérsele conferido otra comisión.” 

No word on why, though.

Copy of telegram from Andres Garcia, Visitador General, from Landín's personnel file