and on the Orgatiic Bodies contained in Hailstones. 8fc. 165 



ence in modifying the crystalline forms that were obtained. 

 In the same fall of snow a great uniformity is found in the 

 forms of the separate crystals and of those which compose the 

 flakes ; sometimes there is only one prevailing shape, at others 

 several very different distinct forms exist, falling at the same 

 time. At the commencement of the fall the forms are gene- 

 rally more regular. In different falls of snow the forms of 

 crystallization are scarcely ever alike or liable to be con- 

 founded ; and even after a temporary cessation these are found 

 to alter. In every respect we find the closest analogy between 

 the formation of these crystals and those obtained from solu- 

 tions in which the temperature, degree of condensation, and 

 repose of the liquid, are found to have such influence. Some 

 observations made on separate occasions will better elucidate 

 these remarks. 



Jan. 7, 1846. — There was a fall of snow, the flakes of which 

 consisted of minute crystals of an octahedric form, placed on 

 acicular ramifications of an irregular description. Besides 

 these, small globules of ice studded with minute pyramidal 

 crystals were perceived under the microscope. The snow 

 examined at intervals was found to contain spherical globules 

 without projecting crystals, which towards the end of the fall 

 of snow gradually increased in size, and might be termed sleet, 

 as they were visible to the naked eye: subsequently the sleet 

 gave place to rain, consisting of minute drops. It is impossible 

 to account for the formation of the mace-like particles of snow, 

 without admitting, as in my experiments, two distinct periods 

 or stages in their development. In the first stage the globular 

 particle is deposited, and in the second the projecting pyra- 

 mids are formed from moisture, condensed from either a gasi- 

 form or a liquid state. 



Dec. 11, 1846. — A heavy fall of snow commencing early in 

 the morning, which, after a temporary cessation at about 1 1 

 A.M., continued until 2 p.m. Many of the crystals were very 

 i"egular, thin plates, which presented a hexagonal arrangement; 

 some closely resembled fig. 15 of Scoresby's figures, as given 

 in Koemtz's Manual, without the projecting radii. Some were 

 composed of a very thin hexagonal star, around which nearly 

 circular apertures were disposed at regular intervals, and at 

 the exterior of these six radii. The flakes were composed of 

 irregularly-grouped particles ; some of a lance-shape, size 

 :i:gj5th of an inch ; others regular six-sided prisms, like those 

 of iiost, about ^j'yth of an inch; and lastly, others nearly 

 globular. 



Dec. 12. — At about 10 a.m. there was a slight appearance 

 of snow during nearly an hour. It consisted of separate par- 



