446 TRANSACTIONS OF THE 



gem.s, crowned in a mass of crystallizations, resembling the bastions of 

 fortifications. 



Camphor dissolved in alcohol, and spread upon glass, forms first, under 

 the microscope, a misty looking surface, which, in the twinkling of an eye, 

 becomes perfectly studded with splendid stars, starting forth in perfect 

 form, radiating from centers in six branches of the same length, formed 

 like fern leaves, tapering to a point from a wide base. The crystals are 

 small, being only the one hundred and twenty-sixth part of an inch, and 

 last for a short time only, as the camphor and alcohol are both very volatile. 



But the most beautiful crystals that can be revealed by the microscope, 

 are those prepared from solutions of muriate of ammonia, which, when 

 liquified and placed upon a pane of glass, throws up first from the edges, 

 short dagger-shaped crystals in every direction, perfectly transparent. 

 From these, as they advance, other crystals shoot out in irregular lengths, 

 but perfectly parallel to each other, and at right angles to the main shaft. 

 These are again studded with crystals, which likewise shoot out at right 

 angles ; and from these again others proceed to du indefinite number ; and 

 when the light is caused to fall upon them in the right direction, rich pris- 

 matic colors are displayed, really beautiful to behold — so much so, that no 

 description by words, or delineation by an artist, can convey a full concep- 

 tion of the richness and elegance of the resulting configurations to the 

 mind. 



MURIATE OF BARYTES. 



When this substance is dissolved in water, a clean solution is formed 

 devoid of color, V)'hich crystallizes immediately on glass, with a moderate 

 heat, and by the power of the microscope presents to the eye figures of ex- 

 quisite grace and astonishing delicacy ; but the fluid crystallizes so rapidly, 

 and the glittering filaments, of whose rare beauty I cannot convey adequately 

 an idea, with instantaneous flashes simultaneously disappear, but not before 

 the observer has seen crystals rise, form branches, divide and subdivide 

 into sprays and limbs, spreading their ftiiry boughs over the entire field of 

 view, exhibiting a magnificent appearance if seen by a single light, when 

 every crystal separately acts as a prism in the decomposition of the rays, 

 and the field of view becomes immediately illuminated with the splendor of 

 the rainbow. 



Bichromate of potassa produces crystals in the form of four-sided prisms, 

 of a transparent cherry color, which rapidly advance under the microscope 

 into various configurations, forming single stems first, which heap into 

 thousands of curved shoots, that entwine and interlace until a crystalline 

 net work extends over the entire surface before occupied by the liquid, of 

 rare and surpassing beauty, actually dazzling the eye with their rich and 

 radiant configurations. 



EPSOM SALTS. 



The crystals of this salt are exceedingly beautiful, and as they grow, 

 appear lavishly ornamented with exquisite figures. They shoot out paral- 



