JAa saw these as well as fireworks at the Sydney Gardens Gala to celebrate the King's Birthday.

They were quite different entities( especially for you,Reeba!LOL)

Basically they were small bowls of clear or coloured glass suspended on wires from buildings, trees,garlands or special temporary structures.

Inside the bowls was a quantity of lamp oil which and a wick which was then lit. They were rather like our modern tea light holders, if you like.

Vauxhall Gardens were very famous for their illuminations and this picuter shows how the Bandstand there was occasionally illuminated.

Here is an example of a temporary strucure,albeit a grand one, which was designed by Robert Adam for an illumination to celebrate George III's birthday in 1763.

The design is still in the collection owned by teh British Royal fmaimly, and was recently part of the exhibition held at teh Queen's Gallery,Buckingham Palace entitled George III and Queen Charlotte: Patronage, Collecting and Court Taste.

This is what the exhibiton catalogue has to say about it:

This design is the more elaborate of the two proposals submitted by Adam for a temporary structure to be erected in the garden of Buckingham House in June 1763 at the time of the celebrations to mark the start of royal occupation of the house, purchased in the previous year.

In the event Adam’s other design(also Royal Collection), for a much simpler structure, was used.

A detailed description of the party, which took place at night and employed 4,000 lamps, is included in the Gentleman’s Magazine.

It was arranged by Queen Charlotte as a surprise for the King, at the time of his twenty-fifth birthday.

Adam also made perspective views of both versions of the screen (Sotheby’s, London, 27-28 April 1988, lots 416-17), which clarify the importance of the ‘transparencies’ (large back-lit pictures, within the main architectural features) in the design.

The subject of the transparencies alluded to the King’s role as peace-maker - following the signing of the Treaty of Paris and the end of the Seven Years War in the same year.

This style of decoration had been popular on the continent for many years: in France, Rome and also in Mecklenburg, where a small-scale ‘illumination’ had been staged to celebrate the forthcoming marriage of the future Queen Charlotte in 1761.

It appears that some of the materials used in Adam’s 1763 screen were reused by Chambers in 1768, for the pavilion erected in Richmond at the time of the visit of the King’s brother-in-law, Christian VII of Denmark.