"What's the matter?" asked Tom.
"Look!" was the answer, and he pointed to the paper. "There's where a mistake was made before. We were at least two miles off our course."
"You don't say so!" exclaimed Tom, and, taking the sheet, he went rapidly over the results.
CHAPTER XIX
THE SERPENT WEED
All waited eagerly for Tom Swift to verify the statement of the other mathematician, and the young inventor was not long in doing this, for he had what is commonly known as a "good head for figures."
"Yes, I see the mistake," said Tom. "The wrong logarithm was taken, and of course that threw out all the calculations. I should say we were nearer three miles off our supposed location than two miles."
"Does that mean," asked Mr. Damon, "that we began a search for the wreck of the Pandora three miles from the place Hardley told us she was."
"That's about it," Tom said. "No wonder we couldn't find her."