Crowmarsh Gifford Norman. A north transept with a pointed arch was added in about 1200. The building was restored in 1836 and 1868. In 1139 King Stephen built a wooden fort in Crowmarsh, the first of a series built in opposition to Wallingford Castle, which supported his cousin Matilda during the civil war known as The Anarchy. The forts were probably dismantled as a result of the Treaty of Wallingford of 1153. The castle at Crowmarsh consisted of a wide ditch surrounding an enclosure measuring . In 1701 agriculturist Jethro Tull invented his revolutionary seed drill here. In 1770 nearby Mongewell Park
Down-the-hole drill as the system basically relied on gravity. Debris from the hole was baled out using a baling tube with a clack valve, which was periodically dropped on a winch to capture the slurry, which was then brought to the top of the hole to be discharged. It was only when the DTH system came along that many of the problems associated with the other systems were overcome - with the DTH system the energy source is constantly behind the drill bit, the drill tubes (or drill string) are rigid being only slightly less in diameter than the drill bit, copious