As a boy, Murdoch struggled with dyslexia, making school difficult. But his aptitude for chemistry and engineering kept him at it, and by age 10 he had made his own gunpowder and a gun; he used it to hunt rabbits in his native New Zealand.
He kept up his studies and first became a pharmacist and later a veterinarian, and saw that reusable glass syringes were spreading disease, so he invented the disposable syringe. He also invented the tranquilizer gun, the childproof pill bottle, the silent burglar alarm, and more — he was awarded 46 patents in all. He received the New Zealand Order of Merit, but not much money: he was satisfied that his inventions improved the lives of millions, and decided not to sue the companies who violated his patents.
Murdoch was diagnosed with cancer of the sinuses in 1991; it spread to the roof of his mouth, part of his jaw, and one eye; they were all removed. He died in Timaru, New Zealand, on May 4. He was 79.