Double-breasted tailcoat of blue superfine wool belonging to sub-lieutenant Ralph Williams Inigo Jones (1851-1930). The collar is cut with the fashionable V notch and still retains an echo of the dandyish styles of the 1820s with slightly gathered shoulders. On the shoulders are a very heavy brass clips which would have been used to secure the epaulettes. These had steadily grown in weight and mass from their introduction in the 18th century. The sleeves terminate in three gilt brass buttons above blue twist embroidery. The cuffs feature three gilt brass domed buttons above blue-twist embroidery above the buttons on each sleeve is a single, narrow stripe of gold lace with a curl. The coat fastens with eight gilt brass domed buttons which feature the crown and fouled anchor.

The breast of the coat is lined with wadding which is held in place with widely spaced rows of running stitch. There is padding under the arms which is covered with black silk twill and quilted. The tails are lined with blue wool. The back of the coat features a pair of hip buttons. Two three-point pocket flaps with blue twist buttonholes and three corresponding gilt brass buttons. The pocket bags are of white cotton and accessed through the tails. There are gilt brass buttons at the bottom of each tail.

To indicate the rank of sub-lieutenant, there is a narrow strip of gold lace with the 'curl'. The rank of sub-lieutenant was introduced in 1861 and replaced that of mate and Assistant Engineers, 1st Class. This marked an important change in these two ranks of warrant officers as they became commissioned officers. Initially, he wore a single strip of gold laceon his cuff with a curl.