I knew I was held back by the undertow, and that there was need of all my remaining strength to get ashore. I increased my efforts, but surged helplessly forward and backward with the rising and falling waves. When I thought I had given my last stroke, a big wave boosted me in, followed by a second and third, until it seemed I must be where I could reach bottom. I let my feet down, down, until my toes at last touched the sand. I dug them in with all my might, and battled desperately to keep my footing. Then came a little swell that lifted me from my feet, and the terrible current swooped me back again. My strength was gone, and I turned on my back to float. "Perhaps I can try again if I rest," I thought, and meanwhile drifted out until the roar of the breakers came but dully to my ears--out where the water was deep and green. Realizing that I paid for every minute of rest by drifting farther from shore, I rolled wearily over, and with slow strokes started back. At this moment Nab stuck his nose from the water not three feet away. When I spoke his name, he came up so that I could put my hand on his neck. For half a minute he was quiet, letting me bear my weight upon him; then he showed by beginning to dive and circle that his motive in coming to me was purely for sport. Every other minute he would shake loose from my hand and then peer at me beneath the water as my head sank under. At last I got such a firm grip on the nape of his neck that I could hold on even when he dived. With my other hand I untied the piece of lasso from round me and tried to put the noose over Nab's head. To this he had objections, and ducked and backed and splashed until I nearly strangled. Forced to give up this scheme, I nevertheless succeeded in getting a cinch round one of his hind flippers close up to the body. "March, Nab!" I then shouted. "Forward, march!" He either had forgotten his lessons or exulted in the fact that he was now at liberty to disobey orders, for instead of heading for shore, he started in the opposite direction. "Haw!" I cried. "Haw! Gee, then, gee!" But Nab would turn neither to right nor left, and dragged me farther out to sea. Thinking I might steer him by his flipper, I gave a jerk on the lariat. What the seal thought I don't know, but when he felt the noose tighten he seemed filled with sudden fright, and plunged into the depths. Instinctively I took a big breath when I saw him disappear, and laid hold of the lasso with both hands. In another instant I was making the longest dive under water that I believe man ever took. It might have been pleasing to glide through the depths under other circumstances and at moderate speed; but following down after this uncertain guide at the rushing pace he set was the worst experience I ever had. I should have let go my hold but for the thought that there was no worse place than that from which I had started.