White Sands NM Johnwill Farris 1940s Letter to Visitors Atomic History Ephemera

Description

This letter is from an central Indiana estate lot of paper ephemera.
Self explanatory - the letter describes conditions that 'guests' may encounter when trying to visit the White Sands National Monument in New Mexico during the 1940s when the US Army was using the White Sands Proving Grounds.
".. we must detain our visitors until we get the all clear signal".
Letter is from Johnwill Farris, an interesting character in the history of the White Sands National Monument. I have included an NPS document with a biography of Farris.
The letter is not signed, just a typed attribution to Farris as author.
The letter is not dated, but content suggests 1943 - 45.
Good condition, small smudge of ink on right side, seen in photos.