I met a friend earlier and he was on crutches. It turns out that last week a "pit bull type dog" dragged him from his bike and then set about savaging his lower leg. He's a big strong bloke and repeatedly punched the dog's head but it was locked onto his leg. Somehow this ended and he spent 5 days in hospital and had 2 operations, including a skin graft. He is in some discomfort but should be OK once his wounds have healed. This got me thinking, cyclists get chased by dogs from time to time and I've had the odd nip. If I can, I try to put a bit of distance between myself and the dog. Sometimes stopping will make them lose interest because the chase is over. How could you defend yourself against an aggressive dog? Hitting it with a pump would be futile. Trying to kick it would be like feeding it another leg. Are there any legal sprays that work? Startle it with an AirZound? The dog in this incident has been impounded by the Police and I should think it's fate is certain.