This beautiful and rare soft paste porcelain tea cup and saucer with the "London" handle was made by the S. & J. Rathbone firm of Tunstall, Staffordshire. This particular pattern is pictured on page 139 of Howard Davis' book "Chinoiserie: Polychrome Decoration on Staffordshire Porcelain".
Davis writes: "The style of decoration is characterized by well drawn bold designs...using deep, vivid enamel colors, which can be regarded as a "trademark" of the factory."
The "Tea-house" cup and saucer which he shows are marked only on the saucer with the pattern number 508, the same as this set. He knew of a matching bowl with the factory mark of "the "R" in a sunburst". The S. & J. Rathbone company operated from 1812 to 1835. Information about this company is so recent that it is not mentioned in Godden's marks book.
The cup is 6 cm (2-3/8") high, the saucer diameter is 14.2 cm (5-5/8"). The saucer is in perfect condition. The cup has a tiny chip on the foot rim which is hardly noticeable. Both pieces ring when tapped.
Note: I also have available a matching Rathbone cup and saucer in pristine condition. And another set in the same "Tea House" pattern by an unknown maker, which is marked with a pseudo-Chinese mark.