tom swift had been in dangerous situations before with aeroplanes and other machines of his invention. he had more than once been close to death, and he knew that the only way to get out of a tight corner was to keep his head. now he did not so much fear for himself as for mary.

“is there any danger?” asked the girl, who had sense enough to sit quietly in her seat and not grab tom’s arms or interfere in any way.

“yes, there is danger,” the aviator answered quietly, as he kept at his task of trying to straighten out the plane. “if i can’t bring her up we’re likely to crash.”

beyond a gasp of her breath and a look of terror in her eyes, mary showed no signs of the fear that was within her. yet she was terribly frightened, for tom as much as for herself.

“come up here!” cried the young inventor, speaking to the plane as he might to a horse. he adjusted the levers, pulled back on the one that tended to raise the forward edges of the plane to tilt her nose, and he tried to get the elevation rudder up. but in the end he had to admit that he was beaten.

“she won’t come up!” he gasped.

“then we’ll have to crash!” murmured mary.

tom nodded hopelessly. he reached over and began loosening the buckle of the girl’s safety belt before unfastening his own.

“the only thing to do is to jump when i give the word.”

“is there no chance of saving the plane, tom?”

“i don’t believe so, mary. but i’m not worrying about the machine. i can make another. it’s you!”

tom put his arm around her and she leaned close to him. the machine was dashing downward now at terrific speed, and on a dangerous slant that meant the nose would strike the earth first, driving the engine back upon those in the cockpit. the motor had stopped, whether having been cut off by tom or because of some defect mary did not inquire.

“leap clear when i tell you to,” said tom, as he made one more fruitless effort to straighten the plane out so he could pancake down instead of hitting on the nose. “you go out on that side, mary, and i’ll go on this.”

“if there was only some water for us to land in,” murmured the girl. “if we were only over lake carlopa instead of having to jump on the hard ground, it wouldn’t be so bad, tom!”

“i’m heading for jamison’s cranberry bog,” the aviator answered, pointing to a marshy place just ahead. “it will be a softer place to jump on than the fields or in the woods. i hope we can make it!”

nearer and nearer the earth the plane was descending. in a few seconds more it would be all over, and the machine would crash itself into a mass of tangled wreckage, while the bodies of tom and mary—it was terrible to think of.

“shall i jump now?” the girl asked as she leaned over the edge of the cockpit and saw how perilously close the earth was.

“just a moment,” said tom. “wait!”

he made one last attempt to straighten the plane out, pulling on the lever with all his force. to his joy and surprise it yielded where before it had held firm. back it came to the last notch and, with a suddenness that was like the quick stopping of a falling elevator, the plane flattened out on a level keel just as it started over the big cranberry bog, part of which was flooded with water.

“i leveled her out!” cried the young man. “there’s a chance now that we can make a three point landing and save ourselves.”

the plane, however, had acquired terrific speed during her dive, and was going much faster than would have been the case had she been driving along under the power of the motor and on a level. in this latter case tom could have eased the machine down gently.

as it was, they were going to strike the ground while going at terrific speed. though in their favor was the fact that they could now hit the earth at a long slant instead of at an acute angle.

“shall i jump?” asked mary, who was closely watching her lover.

“no!” he cried. “sit tight! maybe we can do it!”

he was making some adjustments to the wings and tail rudder. the controls had jammed just when they were most needed, but they had now suddenly loosened up in as strange a manner as they had tightened, and this gave tom swift his chance.

he looked down, picking out the best possible spot for a landing, since he could now steer the plane somewhat. the spot he picked was where the water was deepest over the cranberry bog. the plane was not fitted with pontoons for landing on water, and doubtless the under carriage was going to be greatly damaged in the fall. but, other things being equal, a fall into water in an aeroplane is less harmful to the occupants than a landing on the hard ground.

with steady hands and clear eyes that sought for the most advantageous spot, tom guided the almost unruly craft. it was now within a few hundred feet of the earth, and a couple of seconds more would tell the tale.

aside from the rushing of the wind past them, causing a roaring noise in spite of the helmets they wore over their ears, there was silence in the plane, for the motor was still dead. amid the silence tom heard some voices shouting below him.

he wondered dimly who could be calling, but guessed it was some autoists on the highway that bordered the cranberry bog.

“they’re going to see something they didn’t count on!” thought tom grimly.

“stand up, mary, when i give the word!” said tom to her as he leaned over the edge of the cockpit and looked down. his gaze took in a small automobile racing along the highway toward that part of the bog where he hoped to land.

“stand up! what for?” asked the girl. “shall i have to jump after all?”

“no, but by standing, instead of sitting, the shock of landing will be less,” tom said. “get ready now!”

his eyes were measuring the distance. in three seconds more, he calculated, the plane would crash into the bog of mud and water. but it would crash on a nearly level keel instead of on its nose, in which case nothing, in all likelihood, could have saved the occupants from death.

“up!” cried tom sharply, and he and mary rose in their seats, clinging to each other.

an instant later the plane hit the ground with terrific force, but fortunately in the middle of a soft spot of mud and water which greatly reduced the shock. as it was, the jolt knocked tom and mary down, stunning them as they were crushed back into their seats, so that for a few seconds after the forced landing they did not realize what was happening.

mary was the first to recover her senses. she struggled to a position where she could look over the side of the cockpit and at once cried:

“tom! we’re sinking! we’re almost submerged!”

by this time the young inventor had aroused and, pulling himself to the edge of the cabin space, he glanced over.

“we’re in a bad hole!” he exclaimed.

he learned later that the plane had gone down in what was virtually a quicksand in the cranberry bog—a place shunned by all who knew its dangers.

“what’s to be done, tom?” cried mary. “we got out of the nose dive just in time, but if we’re going to sink in this bog it will be just as bad, though not so quick!”

she saw, in fancy, a slow, terrible death by suffocation in the mud and water.

“let’s jump out and try to wade to solid ground!” she went on.

“no! no! don’t do that!” yelled tom. “it would be sure death! the plane will hold us up for a time—perhaps until help comes.”

“where will help come from?” asked mary. “no one knows we are here, tom.”

before he could answer there came the sound of shouting voices and the tooting of an automobile horn from somewhere in the distance.

“maybe that’s help now,” tom said. “but they’ve got to hurry,” he added grimly. “we’re sinking fast!”