nce upon a time there was a wide river that ran into the ocean, and beside it was a little city. And in that city was a wharf where great ships came from far countries. And a narrow road led down a very steep hill to that wharf and anybody that wanted to go to the wharf had to go down the steep hill on the narrow road, for there wasn't any other way. And because ships had come there for a great many years and all the sailors and all the captains and all the men who had business with the ships had to go on that narrow road, the flagstones that made the sidewalk were much worn. That was a great many years ago.

The wharf was Captain Jonathan's and Captain Jacob's and they owned the ships that sailed from it; and, after their ships had been sailing from that wharf in the little city for a good many years, they changed their office to Boston. After that, their ships sailed from a wharf in Boston.

Once, in the long ago, the brig Industry had sailed from Boston for far countries and little Jacob and little Sol had gone in her. And she had got to Java and anchored near the place where they got water and they had sent some sailors ashore in boats to fill the water casks. And they had got the water and come back; and the boats and the water casks had been hoisted on board, and they had hoisted the anchor and sailed away, through the straits, for Anger. You might not be able to find that place on a map of Java, but that is what Captain Solomon says in his log-book, so it must be right.

They got to Anger the next morning, and Captain Solomon went ashore in his boat, with sailors to row it; for he wanted to send some letters and he wanted to find out what he would have to pay for sugar and for coffee. He had the letters in a bag. There were three that sailors had written; that doesn't seem many letters for a whole crew of sailors to write after they have been at sea for three months, but sailors aren't much at writing letters, anyway. And there were about half a dozen that Captain Solomon had written, and some from the mates; and there was one that little Sol had scrawled to his mother, and there was the great thick letter that little Jacob had written to his mother. Captain Solomon couldn't take little Sol and little Jacob ashore with him because he thought he would be too busy to look after them. The Industry didn't even anchor, but she sailed back and forth, in front of the town, waiting for Captain Solomon's boat to come back.

At last Captain Solomon had heard all the news and had sent his letters and had found out the price of sugar and of coffee and had learned what ships were at Batavia. Batavia is a city in Java, not far from Anger, and Captain Solomon was going there on his way back. And he had got some fresh vegetables and some turtle and some fresh fowl of a Chinaman, and all his errands were done. So he came back to the ship and got on board and the boat was hoisted up and more sail was set; and the Industry sailed on her way through Sunda strait. Captain Solomon called it Sunday strait. A strait is a rather narrow passage from one sea to another. Sunda strait leads from the Indian Ocean to Java Sea; and, after that, there were some more straits leading to the China Sea.

Late in the afternoon the wind got lighter; and as there was a strong current setting towards the southwest, through the straits, they couldn't sail as fast as the current carried them. So the Industry was carried back to Anger; but she started again very early in the morning, when there was more wind and when the tide was different.

When little Jacob and little Sol came on deck they saw three ships, going the other way. They wondered what they were, and they asked the mate. And the mate smiled and said that two of the ships were Dutch and he supposed that they were going to Batavia. And he thought that the other ship was American and he hoped that it would take the letters they had left at Anger. Little Jacob hoped that it would; but little Sol didn't seem to care. And, all of that day, they watched for more ships, and they saw land, now and then, far off on the horizon. It was very hot, for they were almost at the equator; so that even little Sol was contented to keep still. And, towards night, they saw one of the sailors getting the lead line ready.

The lead is just a big lump of lead, like a sinker that is used on a fishing line, and it is tied to the end of a long line that has the fathoms marked on it in much the same way that the log line has the knots marked; but the marks on the lead line are really six feet apart. And the lead itself has the lower end just a little bit hollowed. The sailor who was getting it ready first made sure that the line was all clear, without any knots or kinks in it. And, when he had seen that the line was all right, he took up the lead and smeared some grease on the bottom of it. The sailor was the old man who had given little Jacob the model of the brig.

Little Jacob was surprised. "What is that?" he asked. "Is it grease?"

The sailor was amused. "It's grease," he said, "sure enough."

"And what is it for?" asked little Jacob again. "I hope you don't mind telling me."

"No, lad," said the sailor. "Be sure I'll tell you. It's to bring up some of the bottom so's the cap'n can tell where we are."

Little Jacob didn't understand. "I don't see," he said, "how Captain Solomon can tell where we are, that way."

The sailor laughed. "Well, no," he said. "I s'pose you don't. Well, it's this way. The bottom of the sea is different in different places. In some parts it's mud and in other parts it's gray sand and in others it's black sand and in others yet it's yellow sand, and so on. In the deep oceans it's different yet, but no lead will reach it. And every good sailor man, such as Cap'n Solomon is, should know the bottom he'll find on the course he sails. And when I heave this lead, it tells him how much water he's got under him and the kind of bottom, for the lead brings up a little of the mud or the sand that sticks to the grease. That's how it is."

Little Jacob thought that he understood. "And will you heave the lead now?" he asked.

"I heave the lead when I'm ordered to," said the old man. "But I'm thinking the cap'n won't want it hove till after dark. There's no lights, hereabouts, you see. Lighthouses," he added, seeing that little Jacob didn't know what he meant.

"Oh," said little Jacob. And he went off to find Captain Solomon and to ask him if he might stay up that night, until they hove the lead. Heaving the lead is called sounding. And Captain Solomon laughed and said that he guessed so.

So little Jacob didn't go to bed so early as he generally did, but he stayed up to see them heave the lead. And, about nine o'clock, Captain Solomon called little Jacob and little Sol and told them that they had better be ready, for he was just going to begin taking soundings. So the two boys went to look for the sailor with the lead line.