Silver Dial English Fusee Lever

A 19^th Century English silver dial fusee lever in silver open face case.  Full plate gilt keywind fusee movement with dust cover.  Harrison's maintaining power.  Chased and engraved cock with diamond endstone inscribed "Patent" on the foot, blue steel Bosley regulator.  Unusual plain three arm steel balance with blue steel spiral hairspring. English table roller lever escapement.  Silver dial engraved with an oriental scene in the centre, subsidiary seconds, applied gold Roman numerals, blue steel seconds hand, gold hands.  Plain silver open face case with faded ribbed middle, maker's mark "ILS & Co" in a rectangle.