There may be a gap between what was written in WW1 and what sailors actually sang.

A quick glance through "Naval Occasions" a 1914 collection of sketches of naval life, includes reference to the singing of "comic songs," Kipling's Recessional, "Spanish Ladies," "Sailors Wives" as mentioned above, and "I know of two bright eyes."

"
I KNOW OF TWO BRIGHT EYES - Clutsam

I know of two bright eyes watching for me,
I know of two white arms waiting for me,
I know of cheeks that bum
To greet me when I return.
Oh, Myra! Oh, Myra, I soon will come to thee!

I know a tender heart weeping for me,
I know of two red lips praying for me,

I know a paradise,

A haven from tears and sighs.
Oh, Myra! Oh, Myra, I soon will come to thee!

Victor Record 18021
Copyright 1901 by Hatfield & Co., London, England"