sealed it hermetically.
The blotchy-faced man watched this latter operation with great interest,saying:
"Have a care now, my dear Theodore. The least mishap, and not a pieceof either of us would remain to tell the story."
"_Ja_! Leave that to me," answered Ella's father. "We do not, I agree,desire a repetition of the disaster which happened last week."
Ella, hearing those words, stood aghast.
A week before all London had been mystified and horrified by a mostremarkable explosion which had occurred one night in a house in one ofthe outer suburbs, whereby the place had been set on fire and utterlydemolished. Whoever were present in the house had been blown to atoms,for no trace of the occupants, or of what had caused the disaster, hadbeen discovered. At first it was believed to have been caused by anincendiary bomb dropped from the air, but expert evidence quicklyestablished the fact that something within the house had exploded.
Was it possible that her father and his dastardly companions possessedknowledge of what had actually occurred there?
Suddenly, Drost having handed the tiny sealed tube to Nystrom, thelatter proceeded to place it in position within the box, using mostinfinite care. Then her father turned upon his heel, and came forwardto the door behind which his daughter was standing.
In a second Ella had shrunk back noiselessly into the cupboard, whichthe old man passed in the darkness, and descended the stairs.
He had passed the door of Ella's room when, having gained the bottom ofthe stairs, he paused and whistled softly. In a few seconds Nystromcame forth.
"Come, Fridtjof," he urged in a low whisper. "Let us drink to thesuccess of our expedition to-night, and the victory of our dearFatherland," an invitation which his visitor at once accepted.
Ella heard the two men descend, making but little noise, and a momentlater she crept into the long, well-lit laboratory where, upon thetable, stood the big official-looking despatch-box.
A second's glance was sufficient to reveal the truth even to her, awoman unversed as she was in such things. It was a mostingeniously-constructed infernal machine which would detonate thequantity of high-explosive which she saw had been placed within.
Though her father had taken the greatest precaution to conceal from hisdaughter the exact line of his chemical experiments, yet, if the truthbe told, Ella and her lover had watched carefully, and Kennedy--who hadshared his well-beloved's suspicions--had ascertained, without doubt,that Drost and Nystrom had been engaged in that long, low room beneaththe roof, in treating toluene with nitric and sulphuric acid for severaldays under heat thus producing tri-nitro-toluene--or trotul--that modernhigh-explosive, of terrible force, which was rapidly superseding picricacid as a base for shell-fillers.
At a glance Ella saw that the square steel bomb, fashioned like anofficial despatch-box, was filled with this highly dangerous explosive,and that the thin glass tube which, when broken, would explode it, hadalready been placed in position. Such a bomb, on exploding in aconfined space, must work the most terrible havoc.
In those few seconds the girl verified the suspicion which Kennedy hadentertained. Some desperate outrage was to be committed. That wasquite certain.
A bomb from a Zeppelin could not cause greater injury to life andproperty than that ingeniously contrived machine, the delicatelyconstructed fuse of which, fashioned on the lathe by her father's ownhands, could be arranged to detonate at any given time.
A second's pause, and then the girl, beneath her breath, took a deepoath of vengeance against the ruler of that hated land wherein she hadbeen born.
"Thank Heaven that I am English!" she whispered to herself. "And I willlive--and die, if necessary--as an English girl should."
With those words upon her lips she crept away from the laboratory, downthe stairs to her room, and, swiftly putting on her fur coat, she wentinto the basement, from which she let herself out noiselessly, and thenhurried through the night, in the direction of Hammersmith Bridge.
On gaining the bridge, she saw the red rear-light of a motor-car, andknew that it was Kennedy's. He had drawn up against the kerb, and hadbeen consuming cigarettes waiting in impatience for a long time.
"Well, darling?" he asked, as they met. "I got your message from thetheatre to-night. What is in progress?"
"Something desperate," was her quick reply. "Let's get into the car andI'll explain."
Both entered the comfortable little coupe, and then Ella explained indetail to her flying-man lover all that she had discovered.
The keen-faced, clean-shaven young officer in uniform who, before he hadgone in for aviation duties, had graduated at Osborne, and afterwardsbeen at sea and risen from "snotty" to lieutenant, sat beside her,listening intently.
"Just as we thought, darling," he remarked. "For me, loving you sodearly, it is a terrible thing to know that your father is such a deadlyand ingenious enemy of ours as he is. Truly the German plotters are inour midst in every walk of life, from high society down to the scum ofthe East End. The brutes are out to win the war by any underhand,subtle, and brutal means in their power. But we have discovered oneline of their enemy intentions and, with your aid, dearest, we willfollow it up and, without exposing your father and bringing disgraceupon you, we'll set out to combat them every time."
"Agreed, dear," declared the girl with patriotic enthusiasm. "I havetold you all along of my suspicions. To-night they are verified.Father, and that devilish scoundrel, Nystrom, mean mischief--for paymenttoo--one thousand pounds each!"
"The infernal brutes!" exclaimed the man at her side. "At least it isto you, dear, that this discovery is due. I had no idea what you wereafter when you sent me that wire to-night."
"I suspected, and my suspicions have proved correct," said the girl."Shall we wait here and follow them? They must cross the river if theyintend to go into London to-night--as no doubt they do."
"Yes. They believe you to be soundly asleep, I suppose?"
"I locked my door, and have the key in my pocket," replied hiswell-beloved with a light laugh.
And she, putting her ready lips to his, sat with him in the car at thefoot of the long suspension-bridge, waiting for any person to cross.
They remained there for perhaps half-an-hour, ever eager and watchful.Several taxis passed, but otherwise all was quiet in the night. Now andthen across the sky fell the big beams of searchlights seeking enemyaircraft, and these they were watching, when, suddenly, a powerful,dark-painted car approached.
"Look!" cried Ella. "Why, that's that fellow Benyon's car--he's afriend of Dad's!"
Next moment it flashed past, and beneath the dim light at the head ofthe bridge they both caught a glimpse of two men within, one of whom wasundoubtedly Theodore Drost.
"Quick!" cried Ella. "Let's follow them! Fortunately you have to-nightanother car, unknown to them!"
In an instant Seymour Kennedy had started his engine, and slowly he drewout across the bridge, speeding after the retreating car over the river,along Bridge Road to Hammersmith Broadway and through Brook Green, in adirection due north.
Through the London streets it was not difficult at that hour to followthe red tail-light of the car in which Drost sat with his bosom friendGeorge Benyon, a mysterious person who seemed to be an adventurer, andwho lived somewhere in York or its vicinity.
"I wonder if they are going up to York?" Ella asked, as she sat in thedeep seat of the coupe at her lover's side.
"We'll see. If they get on to the North Road we shall at once knowtheir intentions," was her lover's reply.
Half-an-hour later the pseudo-Dutch pastor and his companion, driven byrather a reckless young fellow, were on the main Great North Road, andKennedy, possessing a lighter and superior car, had no misgivings as toovertaking them whenever he wished.
On through the night they went, passing Barnet, Hatfield, Hitchin, thecross-roads at Wansford, and up the crooked pebbled streets of Stamford,until in the grey of morning they descended into Grantham, with its t
allspire and quaint old Angel and Crown Hotel.
It was there that Drost and his companion breakfasted, while Ella andher lover waited and watched.
Some devilish plot of a high-explosive nature was in progress, but ofits true import they were in utter ignorance. Yet their two Britishhearts beat quickly in unison, and both were determined to frustrate theoutrage, even at the sacrifice of their own lives.
At three o'clock in the afternoon Drost and Benyon drew up at theStation Hotel at York, and there took lunch, while Ella and her loverate a very hurried and much-needed meal in the railway-buffet in the bigstation adjoining.
Then, after they had watched the departure of the big mud-spattered carwhich contained the two conspirators, they were very quickly upon theroad again after them.
Out of the