"Well, I think we're all ready," announced Ned, as he and Koku were helped into their suits and they waited for the glass-windowed helmets to be put on. Once these were fastened in place talk would have to be carried on with the outside world by means of small telephones or by signals.
"Give me axe!" exclaimed Koku, as some of the sailors were about to put his helmet in place.
"What do you want of an axe?" Tom asked.
"Maybe so one them cow fish come along," explained the giant. "Koku whack him with axe."
"He means horse mackerel," laughed Ned. "Give him the axe, Tom. I don't like the looks of those fish, either. I'll take a weapon myself."
Two keen axes were handed to the divers, their helmets were screwed on, and they immediately began breathing the compressed air carried in a tank on their shoulders.
Slowly and laboriously they walked to the diving chamber. Their progress would be easier in the water, which would buoy them up in a measure. Now they were heavily weighted.
To leave the submarine the divers had to enter a steel chamber in the side of the craft. This craft contained double doors. Once the divers were inside the door leading to the interior of the submarine was hermetically closed. Water from outside was then admitted until the pressure was equalized. Then the outer door was opened and Ned and Koku could step forth.
They entered the chamber, the door was closed tightly and then Tom Swift turned the valve that admitted the sea water. With a hiss the Atlantic began rushing in, and in a short time the outer door would be opened.
"If you'll come around to the observation windows you can see them," said Tom, when a look at the indicators told him Ned and Koku had stepped forth.