A diamond-set platinum fob watch by Cartier

A diamond-set platinum fob watch by Cartier, c.1915, the guilloche decorated dial with black Roman numerals and signed 'Cartier Paris', rose-cut diamond borders each side and with larger diamond winder, the movement signed 'Cartier Paris', 18 eighteen jewels, 8 Eight Adjustments, the case back numbered internally 6946 and with French control mark, on black silk soutoir, fittings millegrain-set with diamonds, the central hexagonal link signed 'Cartier Paris Londre 4088' with repeated inventory number to another hexagonal link, missing hour hand, the watch 3cm wide, 39cm total length