Hi Hawknknife,
Hopefully, Feltwad and Joe Puleo will chime in. Both pistols likely were made in Birmingham, England. Neither is London made, although Ketland and Co sometimes labeled their export guns with London. The first is a 2 barrel turn-off pistol probably made in the late 1790s or shortly after 1800. The grooves in the muzzle are designed to accept the barrel wrench or key, which is used to unscrew them. They are export quality but certainly well made. The second was probably made by William Walsingham who worked in Birmingham from 1767-1783. It is a classic second quality turn-off pistol with a box lock. Many were made and exported as well as sold in England for pocket pistols. Your Walsingham pistols are certainly well made and the decoration is competently done, although the engraving is fairly crude. With repect to value, I would suggest you go to a number of antique gun auction sites and look at what Birmingham-made turnoff pistols are fetching these days. They are in pretty good condition.
dave