Task: Question Answering
Input (English): Passage: As a result of Henry's expansion, St Peter ad Vincula, a Norman chapel which had previously stood outside the Tower, was incorporated into the castle. Henry decorated the chapel by adding glazed windows, and stalls for himself and his queen. It was rebuilt by Edward I at a cost of over £300 and again by Henry VIII in 1519; the current building dates from this period, although the chapel was refurbished in the 19th century. Immediately west of Wakefield Tower, the Bloody Tower was built at the same time as the inner ward's curtain wall, and as a water-gate provided access to the castle from the River Thames. It was a simple structure, protected by a portcullis and gate. The Bloody Tower acquired its name in the 16th century, as it was believed to be the site of the murder of the Princes in the Tower. Between 1339 and 1341, a gatehouse was built into the curtain wall between Bell and Salt Towers. During the Tudor period, a range of buildings for the storage of munitions was built along the inside of the north inner ward. The castle buildings were remodelled during the Stuart period, mostly under the auspices of the Office of Ordnance. In 1663 just over £4,000 was spent building a new storehouse (now known as the New Armouries) in the inner ward. Construction of the Grand Storehouse north of the White Tower began in 1688, on the same site as the dilapidated Tudor range of storehouses; it was destroyed by fire in 1841. The Waterloo Block, a former barracks in the castellated Gothic Revival style with Domestic Tudor details, was built on the site and remains to this day, housing the Crown Jewels on the ground floor. 
Question: What did Henry add to St Peter ad Vincula?
Output (English): glazed windows.