Page, Sir Thomas Hyde (1746–1821), military and consulting civil engineer, was born in Harley St., London, son of Robert Hyde Page and his wife Elizabeth, daughter of Francis Morewood. He was educated at the Royal Military Academy, Woolwich, and received the king's gold medal from George III. In 1769 he was commissioned sub-lieutenant in the Royal Engineers and promoted lieutenant in 1774. Although a military engineer, Page began on a civil engineering project at Langstone Harbour near Portsmouth; in 1770 he used closely-packed fascine poles (rather than traditional planking) and pile-driving to embank the harbour, and repaired a breached section of the existing works. He later extended his method to other sea-wall structures in Britain and Ireland, specialising in coastal currents and techniques of managing the flow of harbour water.
In 1775 he was engaged by the master-general of ordnance, Lord Townshend (qv), to examine the Bedford Level (fenland reclaimed in the seventeenth century between Lincolnshire and Cambridgeshire) for further reclamation by drainage. However, after the American revolution broke out, Page volunteered for service and in June 1775 lost a leg at the battle of Bunker Hill. Although pensioned and repatriated, he postponed joining the Royal Engineers’ invalid corps until 1784. As commanding engineer at Dover (1778–82) he established a local defence association there in 1779, one of many territorial volunteer forces raised against a French invasion. He undertook military and civil engineering works along England's south-eastern coasts and navigable waterways, particularly when promoted regional engineer-in-charge in 1782. He improved water supply and coastal protection at military defences, notably Sheerness in Kent overlooking the Thames estuary, and around Harwich and Felixstowe. In 1783 he was awarded the Society of Arts gold medal for his inland navigation and trademark fascine-based embankments, was elected FRS, and was knighted. In 1783–4 Page undertook new works at Dover, including harbour improvements and construction of a breakwater. Accordingly, he published Considerations upon the state of Dover Harbour (1784), one of several treatises on drainage and embankment dating from the mid 1770s. Page was an acknowledged expert, difficult when questioned and ready to criticise, as became plain when he went to Ireland in 1792.
He had travelled to assist Richard Evans (qv) in constructing the Royal Canal between the Liffey's north quays in Dublin and the River Shannon. In Dublin he began well, repairing a major dock breach and making plans for floating docks in the North Lotts area near the new Custom House by James Gandon (qv). However, an angry dispute arose between Evans and the canal's surveyor, John Brownrigg (qv), concerning expenditure and alleged errors in Brownrigg's measurements. While Page supported Brownrigg, the judgement of Solomon was left to William Jessop (qv), the respected English engineer who was already consultant to the rival Grand Canal Company. Page resented Jessop's report, which at best concluded that the project was good in parts, and at worst clashed with Page's views on how it should proceed. Page resigned in high dudgeon and moved north to Ulster. He was engaged in upgrading the dilapidated Newry Canal, built in 1741–2 as Ireland's first canal waterway. He also worked on the South Rock (or Kilwarlin) lighthouse, near Portavogie, Co. Down, constructed by Thomas Rogers in 1793–7.
Back in England, Page was involved through most of the 1790s in further extensive harbour works at Dover and at King's Lynn, Norfolk. He returned to Ireland in 1800 as consulting engineer to the newly established directors general of inland navigation, who temporarily took control of port improvements, normally the remit of the ballast board (Dublin's actual port authority since 1786). Page was commissioned to recommend improvements to the port area, extending his reach to include Howth at the north and Dalkey at the south of Dublin Bay, as well as Wicklow Harbour. He revisited the age-old problem of controlling the sandbar in the treacherous Liffey estuary. Page had approached it on his first Irish visit with the aim of isolating the bar as an island, which he again recommended in 1801. He worked on Capt. William Bligh's estuarine survey of 1800–01: although Page and Bligh recommended a north wall extending from the Liffey's north quays to the Spit Buoy (at the approximate site of the subsequent North Bull lighthouse), Scottish engineer John Rennie (qv) and Capt. Daniel Corneille opted for a barrier containing the North Bull sands behind what in the 1820s became the Bull Wall between Clontarf and the Spit Buoy. Nor had Page much success in 1800 with his practical harbour proposals at Dalkey, particularly for a breakwater, which were abandoned owing to cost. In the same year his proposals for ship canals between the city and Howth peninsula and from ‘Sandygo’ (Sandycove) near ‘Dunleary’ to the Grand Canal Docks at Ringsend met a similar fate, although a new Howth harbour began to develop seriously by 1807. Nor was Page's proposed breakwater at Sandycove adopted. His ill-fated recommendations, vividly reflecting public desire for greater safety and facilities in Dublin Bay, were published in 1801 as Reports relative to Dublin harbour and adjacent coast, made in consequence of orders from the Marquess Cornwallis, lord lieutenant of Ireland, in the year 1800. He also advised on water supply to the Pigeon House complex at Ringsend.
In 1801 he was assigned, in spite of past animosities, to examine the Royal Canal as far as Mullingar, but appears to have departed soon afterwards. Page's Irish experience may have been frustrating except for his receiving the freedom of the city of Dublin in August 1801 (an honour also bestowed on him by King's Lynn and Dover). He continued working on civil and military projects in south-eastern England and advised on harbour plans for Jamaica. He died 30 June 1821 at Boulogne, France.
He married first (1777) Susanna Bastard, widow, of Devonshire; secondly (1783) Mary Woodward of Kent, with whom he had five children; and thirdly (date unknown) Mary Everett, a navy widow.