The following record is taken from 'The Maritime Archaeology of the South Wales Coal Trade Final Report' [1060]   [1061]  [122]

The Dalserf was a one year old single deck steel screw steamship of the port of Glasgow, official number 129439, owned at the time of loss by James Campbell of Middlesbrough. Built in 1909 at Stockton-on-Tees by Richardson, Duck and Company, the vessel was 1,849 and 1,017 gross and net register tons respectively. Length was 260.2ft (79.2m), breadth 40ft (12.2m) and depth 17.7ft (5.5m). Power was supplied by a set of vertical direct acting triple expansion three-cylinder engines, generating 209 nhp from steam supplied by two steel boilers.

The vessel left Penarth in the evening of 9th July 1910, bound for Oban, Scotland with 2,652 tons of coal for the Admiralty. The vessel was under the command of Evan Williams, one of 19 crew. The vessel proceeded down the Bristol Channel in good conditions. However, by 04:00 when the vessel was off the Pembrokeshire coast it was enveloped by thick fog. Just after 08:00 on the 11th, the ship ran onto rocks on the southern side of Grassholm Island, about 9 miles off the Pembrokeshire coast, as a result of navigational errors made by the master. Although the engines were put full astern, the ship remained fast on the rocks and began to fill with water.

The subsequent action of the strong tides experienced in the locality caused the Dalserf to work further onto the rocks and although salvage operations were commenced on the same day and continued until 22nd August, the vessel was eventually declared a total loss and abandoned in a grounded and partially submerged condition. A photograph of the ship taken during the salvage operations exists in the collection of Trevor Owens (Bennett, 1992: 29).

The master was severely censured by the subsequent Court of Inquiry. However, owing to his previous unblemished record, his certificate was not suspended.

The UKHO wreck report, number 12051, describes the wreck as being well broken up in a general depth of 26m, with its bow in 10m of water, the stern in 30m and a boiler (2m in height) in 26m. The seabed is described as rocky with small stones. The wreck description is dated 1979 and the site appears to have been reported to the UKHO by divers in 1968. Bennett describes the wreck as being in 17-23m on a “rock and small stone” seabed, scoured by currents of up to 4.5 knots (2.32 m/s). Bennett describes the position as being 150m south of East Trump, although the accompanying diagram shows it to be west-south-west (Bennett 1992: 30). Visibility is described as being good. Grassholm Island is home to an important gannet colony.