Holy Trinity

Holy Trinity Parish Church, Dorchester. Lead author: KJH

Holy Trinity Church lies on the northern side of High West Street and is the town's Catholic Parish Church. Holy Trinity has origins as far back as the 11th Century but the present building is a 19th Century Grade II listed church. Holy Trinity is named in the 11th Century Domesday Book. It is now a Roman Catholic Church, formerly Anglican, dating from 1875-6, in the Gothic Revival style and designed by Benjamin Ferrey. The present Church opened for worship in 1876. Its south side flanks the street, and it is hemmed in by buildings to the east and the narrow Grey School Passage to the west.

1. The south frontage on High West Street.

2. The northern elevation of the church from the garden at its rear.

Exterior
Holy Trinity Church is largely built of Portland Limestone, and some Purbeck Cypris Freestone, with dressings of Box Ground Bath Stone, and a slate roof. Some sources describe the Portland Stone as ashlar but most is freestone with mortar cement. The Purbeck limestone can be seen in the lowest courses (3). It has also been used, almost exclusively, in the Sacristy/Hall extension shown in Image 2.

3. Cypris Freestones at the base, with Portland Stone above.

4. War memorial in Portland Stone on the south side.

Beneath the nave window is a plaque of Portland Stone that bears a carved winged angel in relief and commemorates members of the church and the parish who died in the First World War (4). Windows, tracery, quoins and string-courses are of Bath Stone, an oolitic limestone of Middle Jurassic age, (5,6).

5. Quoin of Bath Stone contrasted with whiter-coloured Portland Stone.

6. Bath Stone close-up with oolitic texture.

Bath Stone varies in texture and is sometimes quite shelly, with an abundance of crushed bivalve material (7). This is a medium grained, well sorted, hard, oolitic limestone with fragments of fossil shell. It is described as soft and warm yellow in colour when freshly quarried, but it will harden and may turn whiter in colour when exposed to the atmosphere. Image 8. shows a burrow in the Bath Stone. This is a single burrow (termed Skolithos) formed by an animal burrowing into the sediment while it was still soft. The animal may have been a worm or crustacean. This is a trace fossil and another piece of evidence to suggest the environment of deposition was fairly shallow and well-oxygenated.

7. Bath Stone with shelly texture.

8. Bath Stone with Skolithos burrow.

The northern section of the building containing the Sacristy and Hall (9) is built primarily of Purbeck Cypris Freestone (10). These white to creamy limestones are seen in many buildings and walls in Dorchester. They date from the Upper Jurassic/Lower Cretaceous Periods and are known as Cypris Freestones. Cypris is a tiny ostracod (crustacean) fossil, common in the shallow, salty to freshwater lagoons the rock was deposited in. The stone weathers into thin laminations as the main body of the stone is more resistant and the thin separating layers are softer. The Cypris Freestone, (also referred to as Purbeck limestone) was quarried for building limestone in the area of outcrop from Portesham, through Upwey to Coombe valley/Chalbury Camp and Poxwell and is sometimes called ‘Ridgeway Stone’.

9. Entrance to the Hall showing construction of Cypris Freestone with Bath Stone door frame and windows.

10.Close-up of the laminated Cypris Freestone blocks.

The Interior
Bath Stone from Corsham Down is used internally. The interior of the church is not open to casual visitors but has a beautiful font of Devonshire Marble and a pulpit of alabaster. The altar is of marble with travertine panels. The arcade pillars have been whitewashed so it is difficult to determine whether they are Corsham Down Bath Stone or Portland Stone.

11. The interior looking east.

12. Interior looking west.

A beautiful reredos of carved and gilded woodwork is the dominant feature of the interior at the east end above the high altar. Carved at Oberammergau, it was installed in the church in 1897. (13) The lower altar (14) is of marble with travertine panels. It has a marble plinth. The central panel shows the Virgin Mary flanked by angels.

13. The high altar with reredos.

14. The lower altar.

15.The High Altar with its marble surround and travertine panelling.

16. High Altar detail showing marble top.

A number of fittings were installed from the original Roman Catholic church (now the Tutankhamun Museum), including the altar and the Stations of the Cross. The high altar (15,16) has a marble top and beautiful travertine panels. Some sources refer to this as onyx marble but we feel it is travertine! The nave and chancel is divided by shafts of black-polished Devonshire Marble (17,18).

17. Arch dividing the chancel from the nave.

18. Detail of a shaft of Devonshire Marble.

The alabaster pulpit and the marble font are well-executed examples of Gothic Revival architecture in the Early English style with good detailing and use of materials. The pulpit dates from the late-19th century and is made of translucent alabaster. It has a carved figure in relief to the front panel and rests on a stone base. The font is octagonal with an oval marble bowl carried on clustered marble columns.

19. The marble font.

20. The alabaster pulpit.

Acknowledgements
Photography: SA, AG ,KJH ,JS.
Fr. Babu Francis (Priest in Charge), for allowing access to this beautiful church.
References
The Story of Holy Trinity Church by James Pellow
DBS website
Roman Catholic Church of the Holy Trinity, Dorchester - 1119072 | Historic England
Holy Trinity Catholic Church Dorchester
Holy Trinity Church, Dorchester - Wikipedia
Dorchester | British History Online