Chap 13, part 2.a
The next thing was to find food and shelter. It was now that I began to realize that my own condition was not so good; it was not the island that was pitching and rolling. It was me. I could not walk without at least one oar. And my mind functioned only with the greatest difficulty, even after I had tried every device I knew to get a grip on my thoughts. This is illustrated best by the incident of Jimmy's pants.
The buttons had come off and the zippers had been put out of commission by salt water and salt air. The poor kid kept losing them as he crawled along. I though deeply and laboriously on what I might do for him. Earlier I had tied on my own trousers with cord, but it didn't occur to me to fix Jimmy up the same way.