Gold Pair Cased English Ruby Cylinder

An early 19^th Century English ruby cylinder in gold pair cases.  Full plate gilt keywind fusee movement with Harrison's maintaining power. Unusually shaped engraved cock with diamond endstone, the signed gilt dust cover pierced to reveal the table.  Plain three arm flat polished steel balance with blue steel spiral hairspring, silver regulator disc.  Ruby cylinder, large steel escape wheel, pivots with endstones. White enamel dial with subsidiary seconds, Roman numerals, gold hands. Lateral steel stop lever.  Substantial matching plain 18 carat gold pair cases, gold pendant and bow, maker's mark "IR".