KOtJN IN PLANO. Vl 



and a piano-forte. Any question asked into one of the trum- 

 pets, will be immediately reflected back to the orifice of the 

 tube, and distinctly heard by a person in the funnel, and 

 the answer utteced by them, era song or tune Irom the piano- 

 forte will be distinctly heard at the mouths of the trumpets, 

 but no where else, and there it will seem to come precisely 

 from the interior of the globe. A small hole closed with 

 glass is ^eft through the funnel and side wall of the room, as 

 Sit w, by means of which the concealed person has an oppor-r 

 lunity of observing and commenting upon any circumstance 

 which may take place in the room. 



VIII. 



Mr. William Russel. of Neuman Street, has offered Pro- 

 posals for publishing, by Subscription, two Engravings of tlie 

 Moon in Plano. By the late John R«§sel, ^5y. R,A. 

 with the following adress, 



JL HE late Mr. Russel^ celebrated amongst men of science 

 for the production of the Lunar Globe, left, at his death, 

 two Lunar Planispheric Drawings, the result of numberless 

 telescopic observations scrupulously measured by a micrometer: 

 one of which Drawings exhibits the Lunar Disk in a atate of 

 direct opposition to the sun, when the eminences and depres- 

 sions-are undetermined, and every intricate part, arising trom 

 colour, form, or inexplicable causes, is surprisingly developed 

 and exquisitely delineated ; and the other, of precisely the 

 same proportion, represents the eminences and depressions of 

 the moon determined as to their form with the utmost accuracy, 

 producing thpir shadows when the sun is only a few degrees 

 above the horizon of each part. The former of these was 

 beautifully and most correctly engraved by Mr. Russell, who 

 had likewise very considerably advanced in the engraving of 

 the latter, when death terminated his labours ; it is, however, 

 left in such a forward state, that it will be finished with the 

 greatest exactness, and all possible dispatch, 



Mr. William Russell, son of the late Mr. Russell, proposes 

 to publish, by subscription, these lunar plates, which have been 



