June 15, 1888.] 



SCIENTIFIC NE^VS. 



557 



REMARKABLE HAILSTONES.-I. 



HAILSTONES occasionally assume shapes and sizes 

 not easily accounted for. In their ordinary form 

 they may be regarded simply as drops of water which in 

 their descent have encountered a colder stratum of air and 

 have been frozen. But the case is often exceedingly 

 complicated : we hear authentic reports of hailstones 

 formed of concentric layers, like the coats of an onion ; 

 alternately of clear, hard, transparent ice, and of a 

 loose, opaque matter, like compressed shots. Perhaps 

 the most remarkable hailstorm on record is one 

 mentioned by Abich as having occurred near Tefiis in the 

 summer of 1 87 1. The stones were of the size of a hen's 



times singly and sometimes grouped together, as in Figs. 

 I and 2. Their forms were often slightly rounded 

 by the fusion of the edges and surfaces. In these 

 crystals the rhombohedric system was distinctly re- 

 presented in numerous modifications. Most frequently 

 these crystals consisted of short six-sided prisms with 

 obtuse rhombohedric terminal surfaces. Frequently 

 also there projected prismatic crystals of nearly three- 

 fourths of an inch in length, with converging edges, pro- 

 duced probably by the most acute rhombohedra. With 

 these crystals there were also grouped the hemihedric 

 forms of the scalene octohedron with rhombohedric ter- 

 l minal surfaces of considerable size. 



Fig. I. 



egg, a magnitude by no means unexampled . On exam- 

 ination there was found in almost all a central spherical 

 or spheroidal nucleus coated in part with a crystalline 

 structure, thus indicating two distinct phases in their 

 formation. The nucleus was a spheroidal body of pure 

 ice, enclosing a number of fine air-bubbles, and con- 

 sequently not very transparent. Of the same texture 

 was an intermediate layer, enclosed in a whitish stratum. 

 From this nucleus there issued a number of whitish 

 radiating stripes, like the spokes of a wheel. The space 

 between these six radii was almost pure ice, translucent 

 like that of a glacier, and containing a number of small 

 pear-shaped pores, which seemed to issue from the centre. 

 From the surface of the central bodies as thus consti- 

 tuted there arose crystals of pure, transparent ice, some- 



FlG. 



Along with these columnar formations, which re- 

 minded the observer of the calcareous spar crystals from 

 the Andreas mine, there occurred also clear crystals with 

 expanded end surfaces and dihexahedric terminal edges, 

 which resembled the well-known forms of specular iron 

 ore. At the beginning of the storm Herr Abich had 

 observed certain tabular crystals arranged in flower-like 

 circles like the " iron-roses " of St. Gotthardt. But he 

 could not find any such specimens among the heap of 

 hailstones which had been collected for examination. 

 It will be understood that the descriptions of the hail- 

 stones, or rather hail-masses, as just given, cannot be 

 regarded as the result of a formal, minute, crystEllo- 

 graphic examination. In executing the drawings Herr 

 Abich aimed at a correct reproduction of the lines 



