Call me a pedant but I've always been puzzled by the word "jack", as in lazy or selfish. I assumed it came from "Fcuk you Jack, I'm alright", in which case if you were "Jack", you'd be the hard-done-by one!
And the Lynx Gem Engine mount, from the practice of calling Aircraft Engines "Donkeys" or "Donks". Other Lynx parts included the Bonk, Knife-edge, Dangleberry, Broom Cupboard, and a thousand other stupid made up names.
Nothing to do with the Indian Mutiny but in the pre-anaesthetic days,the practice of giving a wounded soldier a bullet to bite on prior to surgery.
Oddly enough, I'm in the middle of reading a book which quotes from The (American) Army Medical Journal ;
'The real reason that soldiers in the pre-anesthesia era were given a bullet to bite on was not to help them endure the pain but to quiet their screams'
Correct. IIRC the Indian Mutiny was about biting the top off small paper bags that held the powder charge. The bags were coated in animal fat to keep them dry and the origin animal (was it pigs or cows?) caused offence.
Again, could be bollocks but Primary School was a while ago for me.