There were few pa.s.sengers on the trolley so early in the morning and not many stops to make, so the motorman turned on the power full and made the vehicle speed along.

Mile after mile was covered and finally the car reached the top of a long hill. At the foot of this the line came to an end, and the boys had a two mile tramp before them to reach the lonely spot where the _Porpoise_ was docked.

Down the hill the car started. The motorman shut off the electricity and let the vehicle run by its weight.

Faster and faster it ran, the dust flying in a cloud about it.

"Better put the brakes on a bit," called the conductor. "It's gettin'

kinder speedy, Hank!"

The motorman twisted the handle. There was a grinding noise as the shoes took hold on the wheels. Then a chain snapped and the car seemed to leap ahead.

"The brake's busted! I can't stop the car!" yelled the motorman.

Vainly he twisted at the handle. Then, seeing he could not stop the trolley car he made a desperate jump off the vehicle and landed in a heap on the side of the road, rolling over and over.

"Reverse the current!" cried one of the pa.s.sengers, to the conductor.

"That ought to stop her!"

The conductor made his way to the front platform and turned the reversing lever. Then he applied the current. But it was no use. With a blinding flash and a report like that of a gun a fuse blew out, and that crippled the car completely so far as the electric current was concerned.

"Everybody jump!" cried the conductor. "There's a curve at the foot of the hill, and we'll all be killed if we stay on!"

One by one the pa.s.sengers leaped from the car. Several were badly hurt by the falls they got. Meanwhile the trolley was tearing down the hill at a terrific rate of speed.

"Shall we jump?" asked Mark of Jack.

"We'll be killed if we do," was Jack's answer.

"And we'll be killed if we stay aboard," said Mark.

"Not if I can help it," cried Jack as he started for the rear platform.

"What are you going to do?" asked Mark.

"Put on the other brake. They never thought to try this one! Maybe it will work and stop the car!"

Then Mark saw what Jack was up to and went to help him. The shabbily dressed man seemed undecided what to do. He stood up, holding to the straps to prevent himself from being tossed from side to side as the runaway trolley swayed. He watched the boys curiously.

The lads, reaching the rear platform, twisted at the brake handle with all their strength. They could feel that the chain was still intact. But would the shoes grip the wheels with force sufficient to stop the car?

There was a shrill screech as the brakes were applied by the boys. With all their might they turned the handle, winding the chain up tighter and tighter. At last they could not budge it another inch. Then they waited anxiously.

The car never slackened its speed. So great was the momentum that had both sets of brakes been in working order it is doubtful whether they would have stopped the vehicle. The speed was so great now that one of the journals became hot and the oily waste that was packed in it caught fire, making what railroad men term a "hot box".

"I guess we're done for," groaned Mark.

"We certainly haven't checked the speed any," Jack admitted. "But wait a minute."

He began stamping on the floor of the platform.

"What you doing?" cried Mark, for he had to shout to make his voice heard above the roar and rattle of the car.

"Putting on the sand," replied Jack, as he kicked at the plunger which, being depressed, let a stream of fine gravel out on the rails. "The wheels are gripped I think, and are slipping on the rails. This may help some."

"Let me give you a hand," exclaimed a voice, and the boys turned to see the shabby man standing with them on the platform. He grasped the brake handle, and gave it an additional turn. His strength seemed remarkable for so small a man.

The speed of the car was checked a little, but the vehicle was still speeding along at a rate that would soon bring it to destruction if not halted before the curve was reached.

"That's a little better," observed Mark. "It's a good thing you were here."

"Good for me, not so good for you," said the man with a peculiar smile.

"What do you mean?" asked Mark.

"I mean that I shall have to place you under arrest for attempting to a.s.sa.s.sinate Lord Peckham!" exclaimed the man. "I am Detective Ducket, of Scotland Yard!"

He stripped off a false beard he had donned, and threw back his coat, displaying his shield. He was the same man who had attempted to arrest the boys in the police station at Easton.

"I've got you just where I want you now," Detective Ducket went on.

"There are none of those blooming American police to interfere."

The next instant the car gave a sudden lurch. Then it seemed to rise up in the air. Jack felt himself flying through s.p.a.ce, and he observed Mark, who was clinging to the valise, following him.

There was a terrific crash, a ripping, tearing splintering sound, and the runaway trolley smashed into a big oak tree at the foot of the hill.

The vehicle had completely jumped the track at the sharp curve.

Jack's eyes grew dim, and he seemed to be sinking down in some dark pool of water. He heard a splashing beside him and began to strike out, trying to swim. He seemed to be choking. Then the blessed air and daylight came to him, and he found he was floating on the surface of a pond.

He dashed the water from his eyes and saw, over on the bank, the wreck of the trolley. Then he noticed that Mark was swimming beside him.

"What happened?" asked Jack.

"A little of everything," panted Mark. "Lucky we weren't killed. We must have been flung off the rear platform into this duck pond."

The boys soon made their way to sh.o.r.e, unhurt except for the wetting.

The fall into the water had saved their lives.

"Where's the valise of machinery?" asked Jack.

"There it is," answered Mark pointing to where it had fallen at the back of the pond.

"And what became of Detective Ducket?"

"He's here, at your service!" exclaimed a voice. "Consider yourselves under arrest and don't you dare to leave this place without me."

The boys looked in the direction of the sound and saw the English officer lying on the gra.s.s not far away. He seemed in pain, but had raised himself on his elbow and was pointing his finger sternly at the boys.