188 SIGNS AND SEASONS 



" the gasp and moan 

 Of the ice-imprisoned flood." 



Sometimes it is a well-defined grunt, e-h-h, e-h-h, 

 as if some ice-god turned uneasily in his bed. 



One fancies the sound is like this, when he hears 

 it in the still winter nights seated by his fireside, or 

 else when snugly wrapped in his own bed. 



One winter the river shut up in a single night, 

 beneath a cold wave of great severity and extent. 

 Zero weather continued nearly a week, with a clear 

 sky and calm, motionless air; and the effect of the 

 brilliant sun by day and of the naked skies by 

 night upon this vast area of new black ice, one ex- 

 panding it, the other contracting, was very marked. 



A cannonade indeed ! As the morning advanced, 

 out of the sunshine came peal upon peal of soft 

 mimic thunder; occasionally becoming a regular 

 crash, as if all the ice batteries were discharged at 

 once. As noon approached, the sound grew to one 

 continuous mellow roar, which lessened and became 

 more intermittent as the day waned, until about 

 sundown it was nearly hushed. Then, as the chill 

 of night came on, the conditions were reversed, and 

 the ice began to thunder under the effects of con- 

 traction; cracks opened from shore to shore, and 

 grew to be two or three inches broad under the 

 shrinkage of the ice. On the morrow the expansion 

 of the ice often found vent in one of these cracks; 

 the two edges would first crush together, and then 

 gradually overlap each other for two feet or more. 



This expansive force of the sun upon the ice is 



