Notice the length of paragraphs, sentences, clauses, and his choices in punctuation.

Sometimes someone would speak in a boat. But most of the boats were silent except for the dip of the oars. They spread apart after they were out of the mouth of the harbour and each one headed for the part of the ocean where he hoped to find fish. The old man knew he was going far out and he left the smell of the land behind and rowed out into the clean early morning smell of the ocean. He saw the phosphorescence of the Gulf weed in the water as he rowed over the part of the ocean that the fisherman called the great well because there was a sudden deep of seven hundred fathoms where all sorts of fish congregated because of the swirl the current made against the steep walls of the floor of the ocean. Here there were concentrations of shrimp and bait fish and sometimes schools of squid in the deepest holes and these rose close to the surface at night where all the wandering fish fed on them.

In the dark, the old man could feel the morning coming and as he rowed he heard the trembling sound as flying fish left the water and the hissing that their stiff wings made as they soared away in the darkness. He was very fond of flying fish as they were his principal friends on the ocean. He was sorry for the birds, especially the small delicate dark terns that were always flying and looking and almost never finding [. . .]. Why did they make birds so delicate and fine as those sea swallows when the ocean can be so cruel? She is kind and very beautiful. But she can be so cruel and it comes so suddenly and such birds that fly, dipping and hunting, with their small sad voices are made too delicately for the sea.

[. . .] He looked across the sea and knew how alone he was now. But he could see the prisms in the deep dark water, and the line stretching ahead and the strange undulation of the calm. The clouds were building up now for the trade wind and he looked ahead and saw a flight of wild ducks etching themselves against the sky over the water, then blurring, then etching again, and he knew no man was ever alone on the sea.

He thought of how some men feared being out of sight of land in a small boat and knew they were right in the months of sudden bad weather. But now they were in hurricane months and when there are no hurricanes, the weather of hurricane months is the best of all the year.

If there is a hurricane you always see the signs of it in the sky for days ahead, if you are at sea. They do not see it ashore because they do not know what to look for, he thought. The land must make a difference too, in the shape of the clouds.

He looked at the sky and saw the white cumulus built like friendly piles of ice cream and high above were the thin feathers of the cirrus against the high September sky.