“Ice; splitting on her stem.”
“Then it’s too thin to worry about.”
“That’s the worst kind,” Moran replied, slipping into his pilot coat. “Get your slicker on; I’m going out.”
There was not much to be seen when they reached the deck. Clammy fog enveloped the boat, but Jimmy could see that the surface of the water was covered by a glassy film. He knew that heavy ice is generally opaque and white, but this was transparent, with rimy streaks on it that ran to and fro in irregular patterns. As the tide drove it up the channel, it splintered at the bows, throwing up sharp spears that rasped along the waterline. Still, it did not seem capable of doing much damage, and Jimmy was surprised at Moran’s anxious look.
“Shove the boom across on the other quarter!” Moran said sharply.
Jimmy moved the heavy spar, the boat lifted one side an inch or two, and Moran, lying on the deck, leaned down toward the water. Jimmy, dropping down beside him, saw a rough, white line traced along the planking where the water had lapped the hull. It looked as if it had been made by a blunt saw.
“She won’t stand much of this,” Jimmy said gravely, running the end of his finger along the shallow groove made by the sharp teeth of the splitting ice.
“That’s so. I’ve seen boats cut down in a tide. The trouble is, the stream sets strong through the gut, except at the bottom of the ebb.”
Jimmy nodded. This was his first experience of thin sheet-ice, but he could understand the dangerous power it had when driven by a stream fast enough to break it on the planking, so that its edge was continually furnished with keen cutting points. He could imagine its scoring a boulder that stood in its way; while, instead of changing with flood and ebb, the tide flowed through the channel in the sands in the same direction, as tidal currents sometimes do round an island.
Bethune came up and looked over the side. A glance was enough to show him their danger.