Syon Park Great Conservatory
Designed by Charles Fowler. 35 ft diameter central dome, 65 ft high. The ironwork and brass glazing bars were made by Richards and Jones of Cheapside, Birmingham[1]
1828 'We feel pleasure in recording instances wherein our nobility encourage the manufactures of their country in the improvement and embellishment of their estates. — Messrs Richards and Jones, of the Hot House Manufactory, Cheapside, in this town, have been for some months engaged in the erection of the most splendid and extensive Botanical Range ever executed, for the Duke of Northumberland, and which is so far completed as to be nearly ready for removal to its final destination, Sion House. On Monday last, his Grace, accompanied by another nobleman, arrived in Birmingham, when he took opportunity of visiting the above manufactory, for the purpose of inspecting the progress in the execution of these conservatories, and their attached erections.' [2]
1829 'The splendid conservatory, alluded to in a London paper, is erecting at Sion House, the seat of his Grace the Duke of Northumberland was manufactured by Messrs. Richards and Jones, of Cheapside, in this town. In a short time we may give the particulars of this splendid piece of work, which, we understand, is not exceeded by any thing of the kind in Europe.'[3]
Details of Construction
The conservatory comprises a large central stone-faced structure which includes the distinctive parabolic iron and glass dome, and glazed quadrant wings with glazed pavilions at each end.
The bottom of the parabolic dome sits on a circular cast iron ring, which incorporates gutters and downpipes (Fig 2). This ring is in turn supported by square-section cast iron columns seated on an ornate cast iron ring which incorporates arches (Figs 3 - 7). The arches spring from cylindrical cast iron columns, these columns being in line with the square columns above.
Figs 7 - 10 hint at the method of construction of the arched ring, and indicate the quality of the foundry work. Fig 7 shows a joint at the crown of an arch. Within the space at this location will be seen a bolted joint, and also a vertical rod. The rod has a square head locating in the intrados of the arch, and presumably connects with the square column above. In Fig 8 we see how the 'interlocking circles' castings are bolted to the horizontal ring (note the square-headed nut). The heads of the corresponding bolts are just visible in Fig 7.
At the top of the dome is an ornate scalloped and fluted 'hat' (Fig 11) which can be raised for ventilation. Figs 12 & 13 show the internal arrangement. The operating ropes are just visible in Fig 12. An angle iron ring is visible in Fig 11, bolted to the main ribs. This is presumably used for an access ladder.
The glazing transitions from a cylindrical to a flat form, as can be seen in Fig 5.
Figs 14 - 18 show the elegant ironwork of the quadrant wings.