Frankenstein 1

Captain Walton was sailing far to the north in a ship, near the ice. Suddenly, a sailor at the top of the mast saw something moving on the ice. It was a sled, pulled by ten dogs. He shouted to his sailor friends and they saw the driver of the sled, who was bigger than any person they had ever seen.

The sailors then saw a second sled. There was a normal-sized man on it, and he seemed smaller than the first man.

Two hours later, a sailor on the ship saw the second man again. His sled was broken and he was sitting on the ice. The sailors took him onto their ship.

The man’s name was Victor Frankenstein. When he was on the ship, he wrote his story and told it to the captain.

Frankenstein 1

Captain Walton were was sailing far to the north in a ship , near the ice. Suddenly a sailor, at the top of the mast, saw something moving on the ice. It was a sledge, pulled by ten dogs. He shouted to sailor friends[the crew] and they saw the driver on the sledge who is bigger than any person.

The sailors then saw a second sledge. There was a normal man on it, and he seemed smaller than the first man.

Two hours later, a sailor on the ship saw the second man again. His sledge was broken and he was sitting on the ice. The sailors took him into their ship.

The man’s name was Victor Frankenstein. When he was at on the ship, he wrote his story and told it to the captain.

Alternatives:

"Captain Walton and his crew were sailing far ..." (plural)

It isn't necessary to include "in a ship" this is reasonable to assume:

"... to the far north near the ice."

The lookout at the top of the mast would have been in the 'crows nest'

"Suddenly a sailor, in the crows nest, saw something moving on the ice."

I must find time to read the others ebru...