Question: Who restored a nineteenth-century country house on the southern tip of the Cowal peninsula?

Context paragraphs:
Toward: Toward; (Scottish Gaelic: "Tollard" ) is a village near Dunoon at the southern tip of the Cowal peninsula with views down the Firth of Clyde, located in Argyll and Bute, of the UK country of Scotland.

Ardlamont House: Ardlamont House is a Georgian estate house lying at the tip of the Cowal peninsula, 5.5 km south of Kames, in Argyll, Scotland.  The house was built c.1820 for Major General John Lamont, 19th of Lamont.  It is designated as a Category B listed building by Historic Scotland.  The two-storey house is harled.  The main block has a piended (hipped) slate roof, while the single-storey wings have skew (sloping) gables.  A well-preserved obelisk sundial is located in the garden.

New Castle Lachlan: New Castle Lachlan, is an 18th-century baronial mansion or country house located at Strathlachlan, Cowal peninsula, Argyll and Bute, Scotland.  It was built in 1790 by Donald Maclachlan, 19th laird, to replace the 15th century Old Castle Lachlan, which stands nearby on the shores of Loch Fyne.  The building is protected as a category C(S) listed building.

Loch Tarsan: Loch Tarsan; is a freshwater loch and is an impounding reservoir located 13 kilometres Northwest of Dunoon, on the Cowal peninsula in Argyll and Bute, Scotland.  This three-armed Reservoir extends into both Glen Tarsan and Glen Lean.  It supplies water to the Striven Hydro-Electric Scheme (also known as the Cowal Hydro-Electric Power Scheme).  The larger of the two dams is 17.6 metres high and was completed in 1953.

Cowal Highland Gathering: The Cowal Highland Gathering (also known as the Cowal Games) is an annual Highland games event held in the Scottish town of Dunoon, on the Cowal peninsula in Argyll and Bute, over the final weekend in August.

Cowal Community Hospital: Cowal Community Hospital, formerly known as ""Dunoon General Hospital"", it is a Community Hospital in Dunoon on the Cowal peninsula, Argyll and Bute in the West of Scotland.  It is managed by NHS Highland.  This hospital provides cover for the Cowal peninsula population, numbering some fifteen thousand people.

Castle Toward: Castle Toward (Scottish Gaelic: "Caisteal an Toll Àird" ) is a nineteenth-century country house on the southern tip of the Cowal peninsula, overlooking Rothesay Bay in Argyll and Bute on the west-coast of Scotland.

Cowal Way: Cowal Way; is a waymarked footpath through the Cowal peninsula, in Argyll and Bute, between Portavadie on Cowal and Inveruglas on Loch Lomond side.  The way is fifty-seven miles long.

Auchenbreck Castle: Auchenbreck Castle; (or Auchinbreck) is located on the Cowal peninsula, in Argyll and Bute, Scotland.  Its remains are situated in Kilmodan parish, near the mouth of Glendaruel, 9 km north of Tighnabruaich on the Cowal peninsula.  Little remains of the castle, other than a flat rectangular platform, around 35 by , between Auchenbreck farmhouse and the Auchenbreck Burn.  This is partially bounded by a revetment wall up to 2.2 m high.

Francis William Deas: Francis William Deas (1862 –13 November 1951) was an important Scottish Arts and Crafts architect and landscape designer in the late 19th century and first half of the 20th century.  He was a keen amateur painter, largely of landscapes.  His most important work was probably the restoration of Castle Toward.

Supporting paragraphs: Francis William Deas Castle Toward
Answer: Francis William Deas