Rosen cogs' backstory

She stood quietly in her study looking downwards at a well aged book, the pages were yellowed and aged, and half of them had been burned out during the energy crisis years ago when the main boilers were running low on coal and usable fuels, the last of the flammable materials were spent and there was a rush for anything that could be used to keep the fires running in the boilers to power the city's critical systems.  So as for most of the book being salvaged from a pile of ash during her shift of clearing out the old boilers when they were running on the reserve systems.  It's cover was worn but still easy to read on exception of some of the blackened patches.  “Advanced potions for the wayward traveler.” She read out loud to herself.  Letting out a soft chuckle she flips the book open to the last intact page which is vaguely labeled 'Travel' on the top center of the page, under it was the long list of ingredients required for this new specific brew.  “Root of asphodel, hair of a manticore, hoof dust of the brewer?!  What kind of madness is this?”  She inquired to herself.  “Princess, are you sure that I should test this one?  I've never seen a brew with such specific ingredients, they all seem very rare, thus meaning that this potion does something very.....very powerful.”  She looked over her shoulder to celestia, remembering to adjust her gaze a little as she almost always ended up looking right over the princesses' head as she was quite fond with the princess from a young age and was much shorter years back.  Celestia stood quietly, her peaceful gaze meeting Rosen's questioning look.  Slowly inhaling Celestia hesitates for a moment, thinking the moment over for a few moments.  “I'm quite sure I would like to test this, it may be just what we need to find the resources we need to keep the city running as it needs to be.  These ingredients can be taken from my personal stores at no cost to you.”  Celestia nods slightly to Rosen and stands to her full height, reaching over to her shoulder to dust off the long white, purple, and gold jacket she's adopted in the recent years, after repeated teasing from Rosen and a few stylist ponies that had adopted the new clothes style of the era.  Rosen, quite surprised that Celestia had told her to continue, and not only that but to use her personal stores for some of the more rare brewing ingredients that are only found in very dangerous, and rare locations.  “P-princess?”  She stuttered out.  “A-are you sure?  Thank you for the aid, but, as I said, this must do something big....”  She trails off as she stares into the princess' eyes for what seemed to be an eternity.  Celestia just nodded once more as a darker expression came over her face slowly.  She once more takes a slow, conservative breath before replying to Rosen.  “Rosen, my loyal.....”  Celestia trailed off as she is unsure of what title to call Rosen by anymore, for she's not only a good friend but a Saviour, advisor, engineer, and chemist for her and it's been so long since she's had to address her in a formal manor that she doesn't even know how to go about doing so.  With a sigh Celestia takes another breath and restarts her sentence.  “Rosen, I know you're as curious as I am, and you also know things that I do and this society doesn't.  The coal mines are getting more and more dangerous, our forest supplies are dwindling and our fuel consumption is only growing.  We need to find something, and fast.  I'm afraid that if we don't the fires will fall cold and our city will cease to run.  We've gone so afar and become dependent on machinery, something that I knew was coming but never acted to prevent...  So now if we run dry on resources then people will certainly riot and the nation will fold in on itself in a desperate grasp for something more.  When that happens all will be lost, and the apocalypse will happen all over again, and we've both been through that once before and know the cost of it...  So, we must take large steps forwards and hunt for something to keep this nation alive.....it's better that we take the drastic grabs in the dark than everypony residing within the world for it will be chaos when the latter happens.”  With a sigh Celestia turns her gaze towards the ground as the sounds of hoofsteps are head from behind her and they soon reveal themselves to belong to Luna who had been sitting in the shadow for the past few hours of chatter between her elder sister and Rosen.  Luna  stands there quietly and matches her gaze to Rosen's and stares deeply into her eyes, as they meet in the worlds of dreams and Luna was quite frightened by the mechanical dreams of grandeur that she had at first but soon became fond of the mechanical and chemical advances that Rosen had held within her mind.  Luna gives Rosen a polite nod and tips her tall, brown, and metal webbed tophat to Rosen in a sign of greeting.  Rosen nods quietly to Luna in a form of response as she's lost of words due to the recent list of truths Celestia had put so plainly before her.  Luna sighs a little as she takes her final steps forwards towards Rosen, she tips her hat once more as she turns her gaze to the floor for a few moments, obviously thinking intently about the subject matter.  She finally shakes her head a little as she taps her hooves on the ground and finally looks back up at Rosen, glancing to Celestia for only a moment before returning her full attention to Rosen.  She speaks quietly in a soothing tone, but it wavers from time to time as she's a little uneasy about the cold truth.  “Rosen....my dearest child... fate is upon us and we have no choice but to do these things, it is why my sister and I chose you all those years back, though your execution was by our rule we are both glad that we adapted and prevented it...”  Rosen looks at Luna with an intense glare, obviously a hint cross about her bringing up the past and her near execution due to her going awol when she was kicked from her job because of a slight miscalculation on her part and a ruptured steam pipe that damaged numerous machines in the building.  “Luna, I quite re-”  She's cut off as Luna continues in her speech.  “And so as I said the fate has come around to us again and we don't have the luxury of time on our hooves.  We must act quickly, we have three years at the best, even then we have only four weeks until the remote cities will have to be shut down from the main power grid to keep the reserves up.”  Luna then takes a step back, signaling that she's complete with her contribution and is prepared to let the subject matter settle in for a few moments before Rosen makes her reply.  Standing quietly before the two alicorn sisters once more in her life she's caught between a rock and a hard place.  Her options are limited, betray her best friends and let the world fall into turmoil and have the blood of millions on her hooves, or carry through on her work and jump into the experimental potion making in hopes for some kind of salvation for the nation.  She turns her back on the two alicorn sisters and walks out onto the balcony of her home tower, looking down into the now modernized canterlot, the city is suspended in the air as it was before, but now not by a mountain, but by massive hydrogen balloons and steam powered propellers for propulsion and mobilization of the flying city.  The buildings all covered in brass or copper roofs, depending on when they were made, the homes with brass roofs were made before the city was lifted as the metal was in abundance, but the houses with copper were made after the city took flight because it was the easiest metal to acquire as it was not only in large reserves in the city's cargo holds, but also it was salvaged from other communities that had no need for more copper.  Her gaze ventured from the edge of the city, that merged perfectly with the horizon making it look like the land continued onwards into oblivion, to the center spires that orbited each other on two massive cog wheels that were powered by numerous drive gears linked into steam pistons.  The drive gears were connected to tower's walls leading down towards the underground power stations that housed the actual drive pistons and boilers.  She sighs as she takes one last gander at the city and then she turns away from the view and back to the two sisters standing in her study, she sighs once more and steps back inside and looks at her brewing equipment.  “I'll do it.  Bring me the ingredients as soon as possible and I'll do it by tomorrow morning.”  The two alicorn sisters had already left as she turns her gaze to where they were moments ago, left on the ground are the required ingredients and a small note reading “Thank you.”  and nothing more.  She walks to the pile of items and picks them up quickly and walks over to her equipment and begins her work, continuing on into the night tirelessly as she readies her brew for the next morning's testing.  Time continues to pass slowly as she works continuously through the night.  She finalizes the two part brew and sets to two vials of brightly colored liquid out on stands in the windowsill over two candles before she yawns slightly and makes her way towards her own bed as she falls asleep quickly, but still tosses and turns uneasily through the night wondering just what tomorrow might hold.  Her awakening is sudden and harsh, as a blinding flash filled the room along with two loud cracks, she jumps out of bed completely naked as she lunges forwards towards the source of the sound trying to find it's origin, and to her nude surprise she finds none other than the two alicorn sisters.  Her face becomes a bright red as she quickly covers herself with her hooves in attempt to maintain some decency, as she notices the same red in the two sister's faces as well.  She slowly backs away without a word and slips back into her room quickly pulling on her self made clothes and other accessories.  She steps out into the center room of her home looking to the two sisters once more, all three of them stand there blushing deeply in the context of the recent embarrassing exposure.  She breaks the ice with a simple message.  “I completed the brew, I just need to combine the element with the catalyst and.....drink it.”  She looks to her hooves nervously as the two sisters nod quietly and approach her, gently placing their hooves on her shoulders.  Celestia and Luna both speak in unison to her.  “Your sacrifice is appreciated, and your work is some of the most skilled, we wish you the best of luck, and the safest of journeys.”  With that both of their horns glow and surround Rosen in a bright aura, making her feel slightly dizzy for a moment before it's all over.  She looks to the two sisters questioningly and they both reply in unison once more.  “A protection spell of the alicorn families, ready to aid you and bring you back at the greatest of peril if needed.  Just simply call for us and we shall be able to locate and retrieve you from anywhere in the world.”  She nods quietly to the sisters and clears her throat.  “Thank you, your care means very much to me.”  She turns her back on them and walks to the windowsill quickly snatching up the two vials and pouring them into one beaker.  She swirls the liquid around in the beakers slowly, mixing the liquids together into a dark green potion.  Setting the beaker down she looks to the two sisters and nods quietly to them.  “Are you two ready?  I'm set.....this is it.”  She grabs her saddle bags and tosses them over her back and settles them on either side of her flank.  Celestia and Luna nod slowly, not wanting to speak for fear of letting free their own nervous emotions.  Rosen nods silently to them as she picks up the beaker and without hesitation drinks down the sweet, yet tart fluid.  She pauses for a moment as it quickly takes effect.  “Hey guys, I don't know if it's working.....I mean I only feel a little nau-”  She pauses and jams her hoof over her mouth before she can throw up, holding it back as her head starts to spin, her ears start to ring, and her vision starts to fade.  She stumbles uneasily towards the two sisters before she collapses to the ground, and before the sisters can react her body vanishes in a bright orange flash.  The sisters then stand quietly where Rosen had fallen moments ago.....and wait.  Rosen feels a tugging sensation in her gut as she is seemingly free falling in darkness, and she has no sense of direction, that is until she's blinded by another orange flash and then the bright blue of the sky, followed by the bright gold of the roof of the house below her.....wait......far below her, she was at least twenty feet from the ground and falling quickly.  She tumbles through the air squirming uncontrollably until she crash lands on the soft thatched roof of a house on the outskirts of canterlot.  She stands quickly and stares at the surrounding taking it in to be a familiar city....yet not at the same time.....it's her home city for sure, but in a different era altogether.  Having taken in the surroundings she checks that off her list of things to do in her mind and proceeds to the next thing to do.....vomit.....as that was suddenly made mandatory by her churning stomach, and so she does so, vomiting out most of the used potion and a little residual bile.  Having now attended to two things on her impromptu itinerary she falls subject of item number three....passing out.  Her body falls limp on the roof as her senses fail her once more...