Very interesting, long letter regarding Scotland, with two different bishop marks

This is an outer sent by the Metropolitan Life Assurance Society, with a fair CORNHILL 3D PAID cachet and a red octagonal PD mark. The Metropolitan Life cachet is scarce. Interesting item.

This is an entire sent in 1820 from Milk Street to Greenwich. Originally charged 2d, the original charge mark has a red erasure mark through it because, as it was going to Greenwich, it was in the 3d post area. A new 3d charge mark was added alongside.