CRYSTALLIZATIONS. 105 



slide by the application of a very moderate heat. The resulting configurations 

 are of exceeding beauty, and no verbal description, or delineation of the artist, 

 can convey to the mind a full conception of the richness and elegance of the 

 forms that are presented the eye by the magic power of the microscope. Not 

 only is the beholder charmed with the wonderful delicacy and exquisite grace 

 of the figures ; but such is the swiftness with which the fluid crystallizes, that he 

 sees them in the very process of formation, darting forth their glittering filaments 

 in all directions with a velocity truly astonishing. A quick formation belongs 

 to nearly all the crystallizations herein described ; but the very rapid change of the 

 muriate of barytes from the liquid to the fluid state peculiarly impresses this 

 circumstance upon the mind. One combination common to this salt, and which 

 is delineated at A in drawing 156, is found near the edge of the crystallized field. 

 It appears like a collection of shrubs, shorn of their leaves, growing up from the 

 midst of a tuft of rank herbage. The main crystals take no particular direction 

 in reference to each other, and the lateral branches appear likewise to be guided 

 in their course by no especial law. From crystals like these numerous branches 

 proceed, dividing and sub-dividing until an infinity of boughs and sprays are 

 seen, rising from a single stem, and groups and groves of crystal trees spread 

 their fairy foliage over the whole field of view. 



Another beautiful configuration is delineated at B, where the crystalline stems 

 radiate from a common centre, and diverging more and more as they recede 

 from this point, push forth on either side buds and shoots of sparkling crystals, 

 covering the entire circle throughout which they extend with clustering gems. 



A third variety is exhibited at C. The main crystals are here short and thick, 

 their ramifications occupying only a little space. The secondary crystals are 

 parallel to each other and perpendicular to the parent stem ; and from these a 

 third system proceeds, governed by similar laws. 



One part of this last assemblage of crystals is singularly connected with the rest ; 

 for on the same side, from a single point in the principal crystal two shoots 

 emanate obliquely from it and at right angles to each other ; but the lateral spurs 

 from these, observe the same laws, in regard to direction, as those in other parts 

 of this combined figure. The size of the crystalline stems is exceedingly small, 

 the breadth at a, 5, in this specimen, being only one-seventeen hundred and six- 

 tieth part of an inch. 



The crystallizations of the muriate of barytes, like many others, exhibit an ex- 

 tremely beautiful appearance when viewed, not by the diffuse light of day, 

 but by a single light, as a lamp. Each crystal then acts as a prism in decompos- 

 ing the rays, and the entire field of view becomes illuminated with the splendor 

 of the sevenfold tints of the rainbow. 



BICHROMATE OF POTASSA. This salt produces very elegant combinations, 

 the original form of the crystals being that of a four-sided prism. The solution 

 is of a transparent cherry color, and the minute crystals seen by the microscope 

 gleam with a rich amber light. Like those of the muriate of ammonia they form 



