In a few hours Tom had added a small fitting to his power unit to provide for helium substitution. Then the two boys hopped back to Fearing for a second deep-water test. This time, Tom was delighted to find that he could operate comfortably at great depths, as well as rise or descend suddenly without ill effect.
Bud was aglow with enthusiasm. “Boy, we can really explore now!”
After the boys had returned to Enterprises, Tom phoned Arv Hanson and asked that a duplicate of the hydrolung be turned out in the shop as soon as possible. It was ready the following Monday morning, so Tom suggested to his father that the two visit the proposed underwater site and make some sample plantings.
“Great idea, son,” Mr. Swift agreed. “I want to try out your new diving apparatus myself. If it’s successful, we’ll be able to tackle two problems at once-recover the Jupiter prober and start the ‘sea farm.’ “
46 THE ELECTRONIC HYDROLUNG
They flew to Fearing, then went by boat to the farm site, about half a mile offshore. Each carried several of the valuable Far Eastern plants.
The silt beds which Mr. Swift had selected were AERIAL ATTACK 47
just deep enough to keep the plants from being discovered, yet enable them to receive sufficient sunlight.
Tom and his father started their planting. But no sooner had the first plants been embedded than fish darted in to nibble them. Even the roots disappeared into their greedy maws.
“Looks as though we’ll have to build some sort of net enclosure around and over our farm,” Mr. Swift said, after they had climbed back into the 48 THE ELECTRONIC HYDROLUN6