12/20 The fish often finish the process by jumping up through the ice before it has entirely melted. When the cold is very intense, and these springs have frozen up, some of the water is absorbed by the earth, which leaves a vacuum or empty space between the ice and the water; and then the ice gives way under the weight of the atmosphere, and air is admitted into the water beneath." "Well, I 'm glad air-holes are good for something," said Oscar; "they 're troublesome enough to skaters. Jim Anderson skated right into one the other day, and came pretty near getting drowned. But I always keep my eyes open for them. I never got into one yet." "You cannot be too careful when you are on the ice," remarked Mrs. |