LONDON.- The only surviving privately owned example of a Victorian Lion treadle lock-stitch sewing machine is for sale at Bonhams Fine Mechanical Music and Scientific Instruments auction at Knightsbridge on Wednesday 21 April. This dramatic looking machine was made in 1868 for the American market by Kimball and Morton, a Glasgow based manufacturer. In the shape of a noble but friendly looking lion the machine has all its original parts and is so well preserved that it could easily be made to work again. For the past forty years the lion has occupied pride of place in a private house. Only three other machines of this type are known to have survived and they are housed in museums and are either incomplete or restored. It is estimated to sell for between £20,000 30,000. Also featured in the sale is a stunning gold, enamel and split-seed pearl oiseau chantant (singing bird) box (£80,00