“When do you think Mr. Blipper will be here?” Mr. Bobbsey asked of Bob, as the party was leaving.  “I want to talk to him.”

“I don’t know,” was the boy’s answer.  “He doesn’t stay at the merry-go-round as much as he used to.  He lets me and one of his men run it.  He’s away a lot.”

“Well, you tell him I want to see him,” went on Mr. Bobbsey.  “I shall be here to-morrow and the next day.”

“I’ll tell him,” promised Bob Guess.

“Now let’s go see the balloon,” suggested Bert.

“They’re getting ready to send it up!” exclaimed Harry, as they neared the place where the big bag, already partly filled with gas, was swaying to and fro.  Over the bag was a net work of strong cords, and the cords were fastened to the rim of a large square basket.  To the basket were tied ropes, and to the ends of these ropes were bags of sand, thus holding the balloon to the ground.

“What makes it go up?” asked Flossie, as she watched the swaying bag.

“Gas,” explained Mr. Bobbsey.  “They put in the big bag some gas, sometimes one kind and sometimes another, just like the gas in your toy balloons.  This gas is so very light—­it’s not even so heavy as air—­that it wants to go up into the air, all by itself.  And when it is inside a bag the gas takes the bag up into the air with it.”

“And the basket too?  Doesn’t it take the basket?” Freddie asked.

“Yes, the basket goes up with the balloon,” said Mrs. Bobbsey.

“Who goes in the basket?” asked Freddie.

“Oh, the man,” his father answered.

“Do any children go in the balloon?” called out Flossie.  “Any boys or girls?”

“Oh, no!” quickly said Nan, for she did not want her little sister and brother to tease for a ride in a balloon basket.

“I’d like a ride in a balloon,” murmured Freddie.

Just then the wind began to blow more strongly, and the big gas bag swayed to one side, toward a crowd of people who ran to get out of the way.

“Get more ropes!” cried one of the balloon men.  “Get more ropes and sand bags!”

“That’s right!” shouted another man.  “There’s going to be a storm.  I don’t know whether we ought to send the balloon up!”

“Oh, let her go!” cried several in the crowd.  They did not want to be disappointed.  Bert and Harry added their voices to the cries for an ascension.

“Well, we’ll have to tie the balloon down until we get more gas in it,” said the first man.  “Come on now, more ropes and sand bags!”

While these were being brought the Bobbsey twins and their relatives drew as near to the balloon as they could get, closely looking at it.  At times the big bag, partly filled with gas, swayed until it swept the ground.  The basket, too, pulled and tugged at the ropes that held it down.

“What does the man do when he’s in the basket?” Freddie asked.

“Oh, he sits there and rides along up in the clouds,” said Bert.  “I wish I could go up.”