SANDY, an 18 month old Golden Retriever, is placidly homeward bound as he is photographed here, teeth clamped into the wicker basket which contains the family joint. Owned by Mr F C Clarke of Bedminster, Bristol, the dog is uniquely tempttion-resistant. mr Clarke sends him half a mile to the butcher shop, unaccompanied, for the family meat rations. And, although the succulent smell of raw meat hovers only an inch below his nostrils, Sandy has never yet stopped for refreshment on the homeward journey.