Daniel A. Clark on Snow. 133 
weather being very cold, there passed over us one evening, 
a cloud, from which there fell a small shower of rain. The 
cloud was suddenly carried off by a northern blast, which 
congealed the water in the very surface of the snow, and 
covered the face of the earth with ice. ‘The moon was full 
and the evening very fine. When a sufficient time had 
elapsed to permit the ice to form, another cloud appeared, 
from which there fell a shower of snow to the depth, 1 
should judge of three fourths of an inch. ‘Then the sky 
suddenly cleared, the cold became very intense and the 
wind blew a gale. Nature now began her sport. Particles 
of the snow would move on the icy crust from twelve to 
twenty inches, and would then begin to roll making a track 
upon the ice shaped like an isosceles triangle. The balls 
enlarged according to circumstances. I passed in the morn- 
ing under the south side of a long inclined plain, free from 
almost every kind of obstruction. In many instances the 
rolls had apparently descended the hill by their own gravi- 
ty, aided by the wind which commenced the sport, until 
they reached the bottom, or lodged in the path, and were 
of the size of a barrel and some even larger. Thus the 
whole creation as far as the eye could see, was covered with 
snow balls differing in size, from that of a lady’s muff, to the 
diameter of two and a half or three feet, hollow at each end 
to almost the very centre, and all as true as so many logs of 
wood shaped in a lathe. 
I do not know the extent to which this Lusus nature was. 
observed, but I believe to no very great extent. The old- 
est men in the neighbourhood had never witnessed the like 
phenomenon, and all were filled with amazement at the 
spectacle which the fields exhibited in the morning. 
The exhibition depends on so many concurring circum- 
stances, that I suppose it may never have happened in any 
other case. ‘The rain must fal! suddenly and freeze sud- 
denly, in order to prepare a smooth unbroken surface. The 
snow must fall to a given depth, in order to be shoved be- 
fore the wind, and must possess a certain degree of damp- 
ness in order to make it cohere as it moves. ‘The wind 
must rise before the snow becomes fastened to the crust, 
and must blow very hard in order to commence and finish 
the curious process. And even then the balls had beer 
smal] had not the declivity of a hill promoted the opera- 
tion. 
