New Experiments on the Solar Spectrum. 1 39 



sent each a set of rings, pleasingly combined with each other, 

 and the bend may be made to afford various figures still more 

 remarkable. 



Secondly, a glass retort, by its diversity of figure, affords a 

 convenient means of developing new combinations of forms and 

 colors. When the vessel is half full of pure water — when drops 

 of water stand around the neck of the retort — when bubbles, as 

 soap-bubbles, fill the upper part of the vessel — and finally, when 

 different kinds of transparent fluids are introduced into the re- 

 tort, corresponding changes of figures and colors start into exist- 

 ence, too singular and striking to admit of adequate description. 

 Indeed, it seems hardly necessary to describe appearances, which 

 every one can so easily produce for himself. 



Thirdly, a tvinc-glass or beer-glass, (of a recurved figure, flar- 

 ing at lop,) half full of water, is placed on a stand, and portions 

 of it are successively elevated into the prismatic beam. When 

 the light strikes upon the reflecting and refracting surfaces of 

 the upper rim — when it passes through the body of the vessel 

 below — when it meets with the tremulous surface of the water — 

 when it enters the latter — and, finally, when it meets the vari- 

 ous curvatures that form the pedestal of the vessel — in each case, 

 we are presented with images and combinations of color truly 

 novel and admirable. 



Fourthly, double media frequently afford fine images. Thus, 

 if we let the prismatic beam first pass through the upper part of 

 the wine-glass, and then strike on the glass tube, circular zones 

 of many blended hues are developed. 



Fifthly, highly polished metallic reflectors, of curvilinear fig- 

 ures, give reflected images of curious shades and shapes. A 

 cream-cup, of platina ware, having a surface variously curved, 

 reflects an image not unlike an expanded peacock's tail, but far 

 more brilliant ; and a small convex mirror, gives a semi-ellipsis, 

 studded with gems, well representing a pontifical mitre. A boy's 

 cap of shining India rubber affords a pleasing variety of reflected 

 images. 



The foregoing are only a few of the splendid pictures which I 

 have at different times formed by this method. Indeed, since, 

 as already observed, the least change in either the reflecting or 

 the refracting medium, develops new images, varying in form and 

 color, this new field of experiment seems absolutely unlimited. 



