The Time Ship.
The TARDIS.
The TARDIS was a mix of space ship and time machine, though underground train was more the term to describe the machine. When Harry had read the books supplied by George, and he'd made his first full scale time experiments, he had found that the effects of travelling through time was like being shoved into a cement mixer and spun round and round very fast before the disorientation faded somewhat, but it would still be present.
Harry had also noted that the time machines built by George and himself were dangerously open. They allowed for a wide array of vision, and you could see the changing world when the time machine actually travelled through time, but supposing you were travelling through space in such a machine? What if you suffocated in a poisonous environment? Should a time machine not be enclosed in another machine?
Harry had decided to answer those questions, using the scientific discoveries of later centuries when the majority of the human race had left Earth, and gone out into deep space to expand their knowledge. Harry had commandeered two of these ships with their advanced propulsion systems with their high energy power plants, and used them in his experiments to work out the best means of building a time machine that answered the questions above.
The problems he faced were easily solved; the time machine's acutal time drive was comparatively small, and it was easy, when the platternite was examined, for more of the substance to be reproduced with the fusion reactors present in the ships, though the process had to be done carefully. The time drive allowed the ship to travel through time, and when the temporal field was mixed with the propulsion system, Harry was able to travel faster than the speed of light and also travel through time, though instead of just travelling through the years of the future, or speeding through the past as with other time machines, Harry was able to create a static temporal field, preset to travel to a certain time and place without speeding through time in order to get there.
This breakthrough allowed Harry to experiment with different propulsion systems, and when he investigated different means of propulsion he found that the substance of subspace was in fact, quantum foam, subatomic wormholes that could, in 20-21st theory, link all parts of the universe together. Harry found that subspace fields could mould and manipulate the quantum foaml, and he took a small pocket of the amazing substance, and spent over 4 years studying it to find out its general properties.
He found that quantum foam could be expanded, and that artificial wormholes could be created without relying on a natural ones, travelling anywhere he wanted, and more importantly, cut the travel times in half for his ships for half the energy. When Harry had travelled to another galaxy on the other side of the universe in just half an hour, he returned in triumph. But he wasn't finished yet, he wanted to know more about the expansionist property of quantum foam.
Quantum foam was like blowing bubbles, and with some work with subspace fields, Harry was able to expand these bubbles for half the energy. The bubbles fascinated the hell out of him, and he experimented with them before he created one in an incredibly small space. Taking a cargo barrel, Harry used his techniques to expand the interior space by 20% before he locked the pocket dimension in.
Harry pondered and brooded over his recent inventions for a long time, he could see the benefits for a time machine. If he had a time machine inside a pocket universe, then he could travel through time and space without worrying about the irritations of landing and being avoided by the locals of a planet. The possibilities of the kind of time machine he could build with this technology seemed endless to him.
The time machine would be secure, safe, impregnable from infiltration. He could travel for a long period of time inside, with an oxygen supply set up which could work via hydroponic gardens generating oxygen with carbon dioxide absorbed. He could use these same gardens for growing fruits and vegetables, and only meats would need to be gathered. Harry was determined to be as self sufficient as possible with only the most important and essential supplies to be gathered at intervals.
A security system combining telepathic and illusionary devices would stop aliens or humans from finding the time machine, and a special mechanism to change the outer shell via a nanotech and matter-energy system would help change the outershell of the ship giving him his privacy.
Nanotech controlled by a biochemical AI could help build the time and space machine, growing corridors, rooms, laboratories, and control rooms. The number of rooms generated seemed limitless.
Power. That was a problem, as Harry had to find a fool proof means of powering his time machine without refuelling. He could use subspace energy, and put that on the list, but he decided to look out for something to use in space, something with an energy surplus he could use. When he glanced at a sun, he thought of solar power, but that was fraught with problems. Solar energy needed frequent recharging, and Harry had no means of knowing how far away he would have to travel to arrive at a star, and then there was the trouble with gravity. How was he supposed to repell the force of gravity to avoid stars and planets?
Supernova? He could tap into a supernova, and convert the energy into temporal energy, no problem, but he wanted something more permanent. A black hole. For a year, Harry worked to place a black hole into a pocket universe, out of time and space so then there would be no range, no distance and time, and he ran a subspace energy beam into the ergosphere, where the energy would spin round and round, gathering energy all the time before it was passed out of the pocket universe, to be transmitted through a permanent wormhole gateway to the TARDIS power system, providing enough energy to maintain the pocket universe.
Engines. A number of wormhole drives linked together allowed the TARDIS to travel virtually instantaneously to worlds outside human influence, with a number of redundant propulsive drives for normal outerspace propulsion, and a gravity drive for conventional atmospheric flight. A temporal drive, and redundant spares, with rods of plattnerite inside with the energy from the singularity reactor purifying the radiation from the rods, allowed unlimited temporal travel.
Construction. Outside the time machine was the base form in the shape a sphere, with the gravity drive components and the atmospheric cycling systems with brought in fresh air via the dimensional stabilisers. This sphere contained; the doorway, the links to the pocket universe, the gravity drive, ballast tanks in case the sphere landed on the water, and allowed the sphere to submerge or float. The sphere contained instruments that included the scanner, the seismic detectors, the gyroscopic stabilisation grid, the electrode defence system to prevent unwanted guests from touching the hull. The envionmental probes were also stored in the sphere.
The interior dimension. Grown from a bubble grown in quantum foam, the interior dimension has two main openings, one is the entrance and the other is the terminus for the wormhole where the energy is sent inside to the power drive. The interior dimension can be preset to a certain size, and is grown from nanotech to grow the rooms and corridors via the blueprint computer plan, which the TARDIS matrix contains. The TARDIS matrix is, in fact, part biochemical and part machine, with synapses similar to those of a human brain.
The interior dimension contains laboratories, workshops, rooms for people to live in with self sufficiency built in, a hydroponic garden and a water room, where oxygen is combined with hydrogen to generate water on a grand scale. The power room where the energy of the TARDIS is brought in, and then distributed throughout the ship.
An astrometric and temporal laboratory, where the TARDIS can chart the universe both in spatial and temporal terms. A 3d holographic mapping table allowed Harry to visualise other places as they would be in the past and in the future, and a temporal lab would allow him to see the past, and see how say the Ancient Mayans lived.
For entertainment, there was a fully equipped gymnasium with cross trainer, bike, a full complement of weight lifting machines, a rowing machine, and a treadmill. Harry had his own set of rooms; a common room where he could watch any number of dramas spanning centuries, a library where he could read, a bedroom, a bathroom with ornamental though simple appliances, and training room where he could train via holograms to keep his combat skills honed.
A telescope with a holographic lens allowed him to see things beyond the confines of the TARDIS.