210 



face acquires by the absorption of the liquid into the pores of the 

 paper. He also explains a method by which the impression thus 

 made, and which is only transient, can be rendered permanent. 



This method of observation is then applied to the further exa- 

 mination of various points connected with the distribution of the 

 thermic rays, the transcalescence of particular media, the polari- 

 zation of radiant heat (which is easily rendered sensible by this me- 

 thod), &c. The reality of more or less insulated spots of heat dis- 

 tributed at very nearly equal intervals along the axis of the spec- 

 trum (and of which the origin is prohahly to be sought in the flint 

 glass prism used — but possibly in atmospheric absorption) is esta- 

 blished. Of these spots, two of an oval form, are situated, the one 

 nearly at, and the other some cMstance beyond the extreme red end 

 of the spectrum, and are less distinctly insulated ; two, perfectly 

 round and well-insulated, at greater distances in the same direction; 

 and one, very feeble and less satisfactorily made out, at no less a 

 distance beyond the extreme red than 422 parts of a scale in which 

 the whole extent of the Newtonian coloured spectrum occupies 539. 



A paper was also read entitled, " Remarks on the Theory of the 

 Dispersion of Light, as connected with Polarization ; " by the Rev. 

 Baden Powell, M.A., F.R.S., and Savilian Professor of Geometry, 

 Oxford. 



Since the publication of a former paper on the subject referred to, 

 the author has been led to review the subject in connexion with the 

 valuable illustrations given by Mr. Lubbock of the views of Fresnel ; 

 and points out, in the present supplement, in what manner the con- 

 clusions in that paper will be affected by these considerations. 



A paper was also read, entitled, " Further Particulars of the Fall 

 of theColdBokkeveld Meteorite;" by Thomas Maclear, Esq.. F.R.S., 

 in a letter to Sir John F. W. Herschel, Bart., K.H., V.P.R.S., &c. 

 communicated by Sir John Herschel. 



This communication, which is supplementary to the one already 

 made to the Society by Mr. Maclear, contains reports, supported by 

 affidavits, of the circumstances attending the fall of a meteoric mass 

 in a valley near the Cape of Good Hope. The attention of the wit- 

 nesses had been excited by a loud explosion which took place in 

 the air, previous to the descent of the aerolite, and which was at- 

 tended by a blue stream of smoke, extending from north to west. 

 Some of the fragments which had been seen to fall, and which had 

 penetrated into the earth, were picked up by the witnesses. One 

 of them falling on grass caused it to smoke ; and was too hot to ad- 

 mit of being touched. The mass which was sent to England by 

 H.M.S. Scout, weighed, when first picked up, four pounds. The 

 paper is accompanied by a map of the district, showing the course 

 of the aerolite. 



A paper was also read, entitled, " An account of the Shooting 

 Stars of 1095 and 1243 ;" by Sir Francis Palgrave, K.H., F.R.S., &c. 



