On Heat and Light as transmitted througli Glass. 467 



Copernicans who never expressed their opinion in print, and 

 it must be noted that Harriot had been styled a " profounde 

 mathematician" as early as 1593*. 



In Caxton's " Ymage or Myrour of the Worlde," printed 

 in 1482, the world and its inhabitants are compared to a large 

 apple surrounded with flies. I mention this, not that it has 

 any relation to the subject in hand, but because I met with 

 it while pursuing these researches, and because it ought al- 

 ways to be quoted in connexion with the most improbable and 

 absurd tale of Sir Isaac Newton and the gravitation apple, which 

 is gravely inserted in work after work. What a pity it is 

 that no such tale has been invented to commemorate the dis- 

 covery of Copernicus ! for notwithstanding the prophecy of 

 Rheinhold, his reputation requires it more than that of New- 

 ton: — " Tota posteritas grato animo Copernici nomen cele- 

 bravit, cujus labore et studio, doctrina ipsa coelestium motuum 

 propemodum collapsa iterum restituta est: et magna ejus 

 quoque lux, Dei beneficio accensa, inventis et patefactis ab 

 eo multis, quse ad banc usque setatem vel ignota vel ob- 

 scura." 



35, Alfred Place, London, March 7, 1840. 



LXIX. On certain Modifications of the Po'wers of Heat and 

 Light nxihen transmitted through Glass. By Charles T. 



CoATHUPE, Lsq. 



To the Editors of the Philosophical Magazine and Journal. 



Gentlemen, 



^HOULD the following observations " On certain modifi- 

 ^^ cations of the powers of heat and light when transmitted 

 through glass" appear to you to be a pertinent sequel to some 

 of the experiments of Professor Draper of New York, which 

 are recorded in the London and Edinb. Phil. Magazine for 

 February 1840, they are presented to you with the author's 

 best respects. 



In a room about 16 feet square, having a window about 

 6 feet square in its eastern side, a small stove in the centre 

 of its southern side, a door communicating with a passage at 

 the northern end of the western side, and a blank wall con- 

 stituting the north side, the following experiments were made. 



(«.) A small 4-ounce stoppered bottle containing a frag- 

 ment of camphor was placed upon a table near the centre of 

 the window that occupied the middle portion of the eastern 

 side of the room. 



* Pierce's Supererogation, by Gabriel Harvey, p. 190- 

 2l 2 



