158 ANNUAL OF SCIENTIFIC DISCOVERY. 



the direction of the fibres being at right angles to the stem, or hori- 

 zontal." Their number varies from one to five, all issuing in vertical 

 or longitudinal lines, which are not always symmetrically disposed 

 around the axis. When the icy excrescences exceed five inches in 

 length, which they frequently do, they are usually considerably curled. 

 3. " Although," as Herschel observes, " the icy sheets seem to have 

 been protruded from the interior of the stem, yet on examination they 

 were found to terminate sharply at its surface, and in no instance did 

 they connect with any formation of ice within. The point of attach- 

 ment was, however, always on the surface of the wood, beneath the 

 outer bark, which the frozen sheets had in every instance stripped oft", 

 and forced out to a distance." The only thing observed by Prof. Le 

 Conte, differing from this description, was, that in very severe frosts 

 the icy sheets were often connected with the formation of ice within ; 

 but from various circumstances it is obvious that in these instances the 

 frigorific action was too intense to permit the phenomenon to be de- 

 veloped in a normal manner. 4. The phenomenon took place in the 

 same plant during several consecutive nights, and when the wood was 

 not rifted frequently from the same portion of the stalk. When the 

 \vood was split, the deposition of ice occurred lower down on the 

 stem, till finally the stalks became completely rifted from the height 

 of six or seven inches to the ground, and this is the reason why the 

 exudations are seldom observed after mid-winter. 5. Stems cut off 

 within three or four inches of the ground exhibited the phenomenon 

 the same as those untouched. The icy sheets never issued from the 

 cut surface, but from longitudinal lines commencing below it and ex- 

 tending towards the root. Plants transplanted to a box of moist earth 

 exhibited the phenomenon much less strikingly than those left in situ. 

 Prof. Le Conte is of the opinion, for various reasons, that we must 

 look to the moist earth for the supply of water necessary for the for- 

 mation of these masses of ice. But before proceeding to the consider- 

 ation of the question by what force and through what agency it is 

 elevated and protruded, he remarks that, " impressed with the idea 

 that the phenomenon is purely physical, having no connection with 

 the vitality of the stem, it seemed reasonable that the remarkable ex- 

 udation of icy columns from certain kinds of earth might be referred 

 to a similar cause." He considers that his observations upon this 

 phenomenon have established these facts among others : 1. It occurs 

 most strikingly when a warm rainy period terminates in clear freezing 

 weather, with the wind from the west or northwest. It is developed 

 at all temperatures below 30 F. ; and in situations which are per- 

 sistently wet it is always in proportion to the depression of tempera- 

 ture. 2. It occurs in soils that are rather firm but not very compact, 

 and is seldom if ever observed in rich, mellow, alluvial soils, abound- 

 ing in vegetable matter. 3. The general appearance of the phenome- 

 non is that of a vast number of filaments of ice, forming in their ag- 

 gregation fibrous columns resembling bundles of spun glass, emanat- 

 ing at right angles to the surface as if protruded in a semi-fluid state 

 from an infinitude of capillary tubes in the ground. The structure of 

 the columns is fibrous, presenting a fine silky, wavy, silvery surface, 



