TV & radio guide - Thursday

The Year 1901 (3.45 R4). Part four: Welfare and Reform.
The Material World (4.30 R4). Including Andrew Barnes (De Montfort) and dermatologist Susan Mayou on the skin's water content.
The Emerald in the Crown (8.00 R4). Declan Kiberd  (Dublin) on Anglo-Irish relations from the famine to Oscar Wilde - part of Radio 4's Victorian season.
The 1900 House Special (8.00 C4). Repeat of the opening programme of last year's series.
Costing the Earth (9.00 R4). Allergies - their causes and cures.
» Horizon : The Missing Link (9.00 BBC2; 9.30 in Wales). In the fossil record, there's a missing evolutionary link between fish and tetrapods. This is about the search for it in the rocks of the Devonian era. An informative journey, apart from a perhaps unnecessary detour featuring an American creationist.
Music Masters (9.00 BBC Knowledge). Profile of the composer » Peter Maxwell Davies .
The Riddle of Pompeii (9.00 C4). First of two Secrets of the Dead specials centres on volcanologist Haraldur Sigurdsson's new theory about the 79 AD eruption of Vesuvius. Pity it clashes with Horizon .
I, Claudius (9.00 UK Drama). The Roman empire, as first seen in the autumn of 1976. Classic drama serial that is perhaps ultimately responsible for all the programmes about Rome we're now getting.
» Planets  - Brief Encounters (9.50 BBC2, 10.20 in Wales). Saturn.
Clive Anderson's Conspiracies (10.30, also 12.15 am BBC Choice). Satanic panics.
» Open Science  (from 12.30 am BBC2). Open University science-night programmes begin with Final Frontier - a Mars special, with the latest discoveries and news of the British Beagle 2 mission to the red planet.