1G2 



THE WORLD. 



a halo seen around the sun by Scheiner in 1530. In this fine set 

 of halos mock images of the sun at the intersection of the cir- 

 cles, termed parhelia and anthelia may be observed. These are 



quite common in the arctic regions, presenting the gorgeous ap- 

 pearance of intersecting luminous arches, studded with opposite 

 and transverse images of the sun ; the formation of these, is 

 undoubtedly owing to the combined reflections of the rays from 

 the natural faces of the snowy crystals floating abundantly in the 

 air. Fringes of colored light, similar to those which form halos; 

 may be observed in looking through the fibres of a feather, or 

 thin streaks of grease rubbed over a glass plate. If a small hole 

 is made in a piece of tinfoil, and held close to the eye, a halo 

 will be seen upon looking at the sun through it, very near to his 

 disc. By comparing the artificial halos tmis formed with the 

 natural ones, Prof. Leslie endeavored to ascertain the size of the 

 globules producing the halos, it being inferred that an aqueous 



