M. MELLONI ON THE POLARIZATION OF HEAT. 



335 



Table II. Source of Heat, Jiame of a Locatelli lamp. 



NAMES 



of the 



substances interposed 



before the introduction 



of the 



calorific radiation 



into the 



tourmalines. 



Calorific transmissions 



through each interposed layer, and 



the same pair of tourmalines 



(No. 9 of the preceding table) 



in the position of the axes. 



Perpendicular. 



Arcs 

 of impul- 

 sion 



Forces. 





3 O"^ -Z, 



■a c3 "c — c 



No screen 



Glass colourless 



coloured (red) 



(orange) 



( yellow) 



(blue) 



(indigo) 



(violet) 



coloui'ed (bluish 



Glasi 



green*) 



Ditto 



Glass (opake black) 



Ditto 



Sulphate of barytes 

 of lime .... 



Oil of colza 



Tartrate of potash and 



soda 



Water saturated with 



saltt 



with 



alum 



with 



tartaric acid .. 



Ditto 



Water (distilled) 



Ditto 



Amber (yellow).. 

 Alum 



mm 

 0-00 

 1-85 

 1-80 

 1-87 

 1-79 

 1-83 

 1-78 

 1-81 



0-74 

 1-93 

 0-81 

 1-98 

 2-60 

 2-71 

 8-49 



2-50 



8-49 



8-49 



8-49 

 0-74 

 8-49 

 0-74 

 3-08 

 2-58 



13-47 

 13-94 

 13-04 

 13-31 

 13-84 

 13-66 

 13-44 

 13-02 



15-95 

 16-85 

 16-76 

 17-52 

 13-18 

 10-54 

 10-40 



9-49 



5-78 

 5-81 



5-76 

 10-76 



5-54 

 10-91 



8-35 

 0-58 



11-76 

 12-15 

 11-40 

 11-66 

 12-07 

 11-92 

 11-74 

 11-39 



13-86 

 14-62 

 14-55 

 15-19 

 11-52 

 9-18 

 9-05 



8-26 



5-06 



5-08 



5-04 

 9-38 

 4-85 

 9-50 

 7-29 

 0-52 



21-91 

 21-79 

 21-57 

 21-90 

 21-89 

 21-78 

 21-68 

 21-92 



5-95 



2-76 



4-35 



1-51 



22-30 



37-63 



38-50 



45-21 



66-60 



66-63 



66-59 

 36-31 

 66-67 

 36-27 

 51-23 

 95-81 



* The physical characters of this species of glass, which acts so differently from 

 the other species of coloured glass in all the phsenomena of calorific absorption, 

 are, 1st, its intercepting almost totally the rays which pass through alum ; 2nd 

 its entirely absorbing the red rays of the solar spectrum. I have already stated 

 that their coloration is jnoduccd almost entirely by the oxide of cojiper. 



+ The temperature of these diflcrcnt saturated solutions was about 15°. 



