Fig. 28.
The figures we have been considering, although possessed of unity of design in a high degree, are found to exhibit no great perfection of structural detail when examined beneath a lens; those that we are about to inquire into belong to a more perfect order, much more minute and very compound.
Fig. 29.
[Fig. 28] is a figure of this class, much enlarged and drawn as seen beneath a microscope. It was highly crystallized, and the angles and planes of which it is composed were sharply and well defined. The prisms at the end of the radii were cut into facets, and glistened with brilliancy, as did the six prisms around the centre. The radial arms were sharply cut, six-sided shafts, very different from the snowy rounded spiculæ of the elementary figures. It was easily discernible to the naked eye, and principally those parts which are white in the engraving, and which communicate to the copy very much the effect of the original when under the full influence of direct light. The centre is laminated, hexagonal in form, and within it we perceive the secondary star of prisms; also that each addition to the radii diverges at an angle of 60°.
[Fig. 29] is another, highly crystallized, and composed of parallel prisms, divergent from the radial arms at an angle of 60°, and without nucleus. The irregular blade-like terminations arise from an ill-advised eagerness in the observation of their originally very complicated structure, by which they were in a moment dissolved, without injury, however, to the symmetry of the figure.
