H2 Management of Light in Illumination. 



of those who were seated round the table were de- 

 fended from those direct rays by the hoop of gauze 

 just described. The room was lighted quite suffi- 

 ciently, and in a most agreeable manner, by the 

 luminous dome and the hoop of gauze below it. It 

 was on these principles that the illuminator was con- 

 structed which I presented to the first class of the 

 National Institute of France, on the 24th March, 1806. 



A description of it was published in the Memoirs of 

 the Institute for the next year, and a short account of 

 it was also published by Mr. Nicholson in his Journal 

 of Natural Philosophy ; but as its usefulness has now 

 been sufficiently established by the experience of sev- 

 eral years, and as it is getting fast into general use on 

 the Continent, I have thought it right not to postpone 

 any longer the publication of such a particular descrip- 

 tion of it as may make it better known in England, 

 where I am very desirous that it should be found 

 useful. 



As lamps in general have hitherto been so filthy, 

 and liable to so many disagreeable accidents, that the 

 name can hardly be pronounced or heard without call- 

 ing up several disgusting ideas, on that account I am 

 desirous that my new illuminator may be called an 

 Illuminator. 



As a description of it would be of little use, unless 

 it were sufficiently detailed and precise to enable an 

 intelligent workman to execute it, even without having 

 seen it, I must take the liberty to be very particular in 

 my account of it. The reader will pass over such of 

 the details as may appear to him to be tiresome. 



As one of the objects principally had in view in con- 

 triving this illuminator was to light a room sufficiently 



