Magnesia House

Reasons for Designation

Magnesia House is listed at Grade II for the following principal reasons:
* Architectural interest: a late-C18 house, possibly a remodelling of an earlier pair of houses of 1733, and a former committee room serving the pharmaceutical laboratories which stood to the E (demolished) retaining good-quality panelling with built-in shelves
* Historic interest: for close associations with the Apothecaries Hall and its role in the production of pharmaceuticals until the C20
* Group value: with the Grade I listed Apothecaries' Hall complex.

Details

627/0/10289 PLAYHOUSE YARD 21-FEB-11 6 Magnesia House

GV II Magnesia House comprises a late-C18 house, possibly a remodelling of a pair of house of 1733, and a small building of 1780-1 known as the Committee Room, now named the Counting House. Altered and extended in the C20, probably in the inter-war period, and again in 1982-85, forming a single office premises.

PLAN: The southern portion, a house of two storeys plus basement, raised to three storeys plus attic in the C20, faces E into Playhouse Yard, and abuts Apothecaries Hall to the W; its N elevation faces the Apothecaries' Hall yard. The northern part, the Counting House was originally one storey high, raised to four storeys in 1982-5. The ground floor is linked to the Counting House by a doorway. Above ground floor the buildings are conjoined to form one large room.

EXTERIOR: Front (E) elevation is of three bays and comprises two distinct parts demarcated by a straight joint in the brickwork. The two-bay house to the S is built in brown brick laid in Flemish bond. Areas of brickwork have been repaired, and the third floor is in red brick. The entrance is in the right-hand bay and has a pedimented doorcase with scrolled brackets and panelled reveals. Ground floor has a pair of blind oculi flanking the door and window. The S return into Playhouse Yard is curved, and is enclosed at ground floor level by a canted wall enclosing a yard, now roofed over. The first-floor window appears to have been lowered to form an entrance or loading bay. The single-bay northern section is also built in brown brick, red brick at upper levels, with a pitched roof. The ground floor is blind. All windows are multi-paned sashes, many reinstated in the C20.

The house's rear (N) elevation has been partly obscured by the 3-storey 1980s extension above the Counting House. The brickwork is C18 at lower levels and has a plat band between the ground and first floor. The ground floor has a tripartite sash window. The first-floor window opening has been re-formed. Windows are C20 replacements and have exposed sash boxes in the early-C18 style. The Counting House, now the ground floor of the 1980s extension, has a single sash window to the bowed W elevation and two on the N, one of which has been modified to form a door. Double-faced brass clock on N wall. Above this, the 1980s extension is built in rendered blockwork, bowed on the W side to follow the profile of the Counting House, while the N elevation is jettied over the ground floor, supported on pillars, and surmounted by a gable.

INTERIOR: The interior of the C18 house has been radically altered and retains no visible features of interest. The Counting House is the only interior with special interest. It has full-height late-C18 panelling with moulded cornices, incorporating shelves. Doorway to right of chimneybreast relocated from left-hand side in 1980s. The vaulted basement is accessed by stone steps from the yard, and also by a stair inserted in the Counting House.

HISTORY: The Society of Apothecaries was incorporated as a City Livery Company by royal charter from James I in 1617, and in 1632 acquired Cobham Hall, the former guest house of the Dominican Priory of the Black Friars. This was destroyed in the Great Fire of London, and the new Apothecaries' Hall, which stands today, was built in 1666-72. From 1672, the Society manufactured and sold medicinal and pharmaceutical products, a function which continued until 1922; its 'Elaboratory' for the first ever large-scale manufacture of drugs was located in the basement of the Great Hall. The business was operated as a joint stock venture, under the 'Proprietors of the Laboratory Stock'. A second company: the Navy Stock, was set in 1703 with a monopoly on the supply of drugs to the Navy, occupying premises to the S and W of the Hall. These were rebuilt 1780-81 and now form the SW return of the Hall complex. In 1822 the two Stock companies were merged into the United Stock, and from 1881 a committee managed the pharmaceutical trade.

The development of the land to the E of the Hall on which Magnesia House stands began c1667 when the Society acquired the site of the cloister, part of the estate of Gideon Delaune, former Master and benefactor of the Society. A row of four dwellings and shops was built in the early 1670s and a garden for the Society created to the N of this. A dwelling described as 'old' is shown on the site of Magnesia House on an early-C18 plan. It had fallen into a ruinous state by 1732, and in the December of that year Francis Hatt, carpenter, took a 72-year lease of the site from the on the understanding that he would replace it with one or more brick messuages at a cost of at least £200, by 24 June 1733. In 1780-81, the row of C17 houses, which stood to the NE of the 1733 houses, was replaced by a 2-storey chemical laboratory range for the Laboratory Stock; a further range was attached to this on the NE side along Church Court. The Committee Room, a single-storey building with a bow front facing W, was attached to the W end of the laboratory range, abutting part of the houses' N elevation.

The date of the rebuilding of the 1733 houses as a single dwelling is unclear, but it seems to have taken place after the construction of the laboratory and Committee Room. An unsubstantiated date of 1792 is suggested, while the original 72-year lease would have expired in 1804, although the rebuilding may have taken place before that date. Plans from the 1732 lease, Roque's map (1746), and plans from a lease of 25 March 1778 showing two separate dwellings as 'houses on lease to Mr Hagan' all show that the buildings had a canted south-eastern return, which is consistent with the property boundary that exists today, but not with the distinctive curved elevation of the present building. Morover, a series of leases of 1786 itemises 'two houses in Glasshouse Yard adjoining the Hall and Laboratory' as leased to the Navy Stock, while the Committee Room 'with stone steps down to the cellar' is leased to the Laboratory Stock. The lease plans of 1732 and 1778 show that the southern house had a cramped wedge plan, one room deep with a tiny yard behind; the northern one was larger and two rooms deep. The laboratory ranges to the E were demolished in inter-war period, and the site is now occupied by Nestor House.

The manufacture of magnesium compounds was an important component of the pharmaceutical industry, and the laboratory ranges of 1781-2 included a magnesia laboratory. It is unclear whether Magnesia House itself was ever used for this purpose, although it appears to have fallen out of domestic use by 1886 when an insurance plan labels the ground floor as the 'Magnesia Room', and shows it as interlinked with the Counting House, labelled as 'Office'. The doorway has been relocated from the left-hand to the right-hand side of the fireplace.

SOURCES: Greater London Council Historians' report, March 1981

REASON FOR DESIGNATION: Magnesia House is designated at Grade II for the following principal reasons: * Architectural interest: a late-C18 house, possibly a remodelling of an earlier pair of houses of 1733, and a former committee room serving the pharmaceutical laboratories which stood to the E (demolished) retaining good-quality panelling with built-in shelves * Historic interest: for close associations with the Apothecaries Hall and its role in the production of pharmaceuticals until the C20 * Group value: with the Grade I listed Apothecaries' Hall complex.

Legacy

The contents of this record have been generated from a legacy data system.

Legacy System number:

508565

Legacy System:

LBS

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