Long eyelashes have been a symbol of beauty since records began.
It's almost a Golden Ratio thing. Long eyelashes create a contrast between the eye and the eyelid, making eyes visibly larger and thus more attractive. Biologically, eyelashes protect eyes from debris and other air particles. So, the longer ones have a health function, too.
I had never heard about eyelash trimming. Surely everyone wants their eyelashes to be as long and thick as plausibly possible?
Yet it crops up, a forthcoming mini-masterpiece of a memoir by Gill Johnson (sister of wine writer Hugh), the nonagenarian author. She describes how an impulse visit to Universal Aunts, the upmarket staff bureau, in 1957 landed her a job as governess to two exquisite boys.