
Nothing to do with birding but I wasn't aware that in both world wars the US Navy had an appeal for people to lend their binoculars for war service. In the first world war 51,217 instruments were received and 31,000 were accepted for naval use. They were returned at the end of the war with a thank you letter, a certificate and $1 payment, only one pair was reported lost!
www.history.navy.mil
By the second world war they were more fussy and only wanted 6x30 or 7x50 Zeiss or Bausch and Lomb binoculars. Can't find as much detail as the WW1 scheme.
The British had a similar donation scheme for the army in the first world war, lots of information about it here https://www.greatwarforum.org/topic/256307-national-service-league-field-glasses-scheme/
Return Letter for Binoculars World War I
Title: Letter, Return of Binoculars, WWI Accession #: NHHC 2016.062 Circa: 1918 Size: 8 x 10.5
By the second world war they were more fussy and only wanted 6x30 or 7x50 Zeiss or Bausch and Lomb binoculars. Can't find as much detail as the WW1 scheme.

The British had a similar donation scheme for the army in the first world war, lots of information about it here https://www.greatwarforum.org/topic/256307-national-service-league-field-glasses-scheme/