FRIDAY is the anniversary of an important medical breakthrough. On March 18, 1718 the baby son of Lady Mary Wortley Montagu was inoculated against smallpox. That will come as a surprise to anyone who knows that Edward Jenner invented vaccination in 1796. But Jenners discovery was different. He found that injecting patients with the cattle disease cowpox protected them against the deadly human ailment of smallpox. Dr Jenner called his treatment vaccination from the Latin word vacca for cow, and it went on to rid the world of smallpox. In the 18th century most people living in British towns and cities could expect to catch smallpox and 20 per cent of those who caught it died. The disease was declared eradicated from the world in 1979. Eighty years before Dr Jenner, Lady Mary used a different method. Her husband was the British ambassador to Turkey and she noticed that the Turks inoculated their children against smallpox, not by using cowpox but by deliberately injecting them with smallpox itself. That was risky about one in 200 died. But the other 199 had lifelong immunity. Lady Mary took the risk with her son and went on to introduce inoculation in England when she returned there. The treatment became quite widespread until Dr Jenner discovered a safer way. So what did Lady Marys son Edward Wortley Montagu do with the life preserved for him by this bold medical experiment? Almost everything you could think of. He spent money like water and was often imprisoned for debt. He married almost as often, but several of his marriages were bigamous so its hard to say exactly how many legal wives he had. He joined the army and was mentioned in dispatches. Then he became a diplomat. Then he persuaded his cousin, our old friend the Earl of Sandwich, to get him elected as MP for Huntingdonshire. (In those days democracy in Huntingdonshire consisted of about 1,500 voters doing what the Earl of Sandwich told them to). Montagu didnt bother visiting his constituency or going to the House of Commons - he was busy elsewhere. He spent most of his time as our MP living in France as a professional gambler, and was jailed in Paris for cheating at dice. His fellow conspirator, jailed with him, was the Honourable Member for Arundel. It makes fiddling expenses seem rather tame, doesnt it?