Magic engine and Letty’s worries

 
 
 ☆
 
 
 One clear afternoon, two months since the great invasion of monsters. We were gathered in the backyard of the premises where the Cocomel Workshop was situated.
 
 In the clearing in front of the workshop, a size roughly that of a primary school’s swimming pool, there were currently rails laid out in an oval shape, and on the inside of it were craftsmen whom I’ve gotten to know by face, getting preparations done to begin the test.
 
 “Let’s start this thing!”
 
 “Okaaay!”
 
 Hearing Duncan’s shout, I gave him a thumbs up.
 
 “Three, two, one, start!!”
 
 In line with Duncan’s countdown, I twisted the dial on the switchbox at hand.
 
 Then, connected to the other end of the cable, a trolley remodelled as a rail car^[1] affixed with a pipe of approximately 15 cm in diameter and 50 cm in length, inside of which magic lights leaked out and the 『Woosh』 sound of flowing air began to be heard.
 
 Woosh… Vooooooooo!
 
 The sound of the wind gradually became more extreme.
 
 “Magic supply, 10%,… 20%,…”
 
 The young boy monitoring the metre from beside Duncan — Jack, who had transferred from the Royal Capital Workshop — read out the metre.
 
 And then it happened once he called out 『30%』.
 The trolley began running atop the rails at last.
 
 ““Yeaah!!””
 
 Those related to the workshop who had been watching let out cheers.
 
 The trolley that had begun moving then steadily picked up speed.
 
 “Wai-, that fast?!”
 
 Then barely a few seconds later, it began roaring down the rails with such force that you would wonder when it would derail.
 
 “Ojou-sama, it’s amazing! It’s running! It’s really running!?”
 
 “I-, it seems so.”
 
 Pointing at the trolley as the attendant’s tension rose, my smile began to cramp.
 
 (It’s a Mini SL^[2]… or rather, a roller coaster, huh. Maybe I should rather make an amusement park.)
 
 As I let out a dry 『Haha』, Duncan, who was operating the trolley via wire from the inside of the track, chased after the trolley.
 
 And then, once it had run two laps of the roughly 50 metre course.
 
 Whooo o o oosh…^[3]
 
 “Huh?”
 
 The magic lights inside the pipe abruptly cut out, and the sound of air cut out as well.
 
 “Magic power supply 0%. The magic power is out!”
 
 Jack, who had been monitoring the meter, shouted this out.
 
 The trolley, which no longer had magic power, slightly eased up on its speed while continuing to run on its inertia.
 
 (No way. Even though it used 4 medium-sized magic stones?)
 
 I was astonished at how excessively fast it ran out of magic power.
 
 “Hey, Jack. Do you know how long it operated for?”
 
 “Wait a moment. Uhm… 23 seconds since activation.”
 
 “Meaning we used a single medium-sized magic stone in under 6 seconds.”
 
 Duncan, while out of breath, chased after the trolley which was still running on inertia.
 
 With that scene in the background, I was troubled by how bad the prototype engine’s fuel consumption was.
 
 
 
 What we were testing was a prototype of the magic jet engine we’re thinking of putting in a railroad locomotive in the future.
 
 Wind is created by a spell activated by a magic circuit, and air is sucked into a Mistreel pipe from the front and spat out at the back.
 Although the structure is extremely simple, the controlling magic circuit became fairly complex.
 
 The reason for this is that in order to make the output characteristic at the time of acceleration as smooth as possible, it switches between multiple stages of powering magic circuits.
 
 If it is a spell, or a magic tool that uses a person directly supplying magic power, then the user can adjust the output to some extent by reducing or increasing their supply of magic power. But to do so mechanically with a magic tool that uses a magic stone as its energy source is quite difficult.
 
 For this experiment, quite a lot of man-hours were spent on developing magic circuit designs and the likes of measurement devices… things like new magic power measurement instruments and all sorts of analog meters.
 
 
 ☆
 
 
 The review meeting after the test.
 With all those concerned gathered in the mansion’s meeting room, Duncan declared something before anyone else opened their mouths.
 
 “Next time we’ll make the cable longer!”
 
 ““… ok.”
 
 Everyone in the room nodded as he said this, having seen him frantically chasing after the running jet trolley.
 
 Well, that is a part that I think should be improved. Yeah.
 
 As it seemed Duncan had said what he had wanted to say for the time being, I continued to talk.
 
 “In the test just now, we confirmed that the engine design runs according to plan. The problem is———”
 
 “——— the mass consumption of magic stones in a short time.”
 
 I nodded at Duncan’s words.
 
 “That’s right. The plan was to enlarge this prototype engine as is and use it as the actual thing, but are you sure it’s alright to carry on as planned?”
 
 “If you’re asking if it’s fine to move onto production of the real thing, I’ll say it is, since we have a good prospect of securing magic stones, but… as expected, it would leave me feeling terrible if we kept it as is without any improvements.”
 
 I then pondered.
 
 By the way, in addition to the portion excavated from the magic stone mine lent to us by His Majesty and the portion secured from the monster raid incident, the amount 『produced』 in a certain way was also included.
 
 
 
 “Wait, wait. Can you really prepare that many magic stones? One medium-sized magic stone is enough for a month’s worth of food, isn’t it?”
 
 Doubtful, Jack looked my way.
 Laughing 『Fufufu』, I spoke to him with a smile.
 
 “Actually, I completed something amazing last month!”
 
 “Huh?”
 
 I can’t tell you the details, but this is how we’re able to secure a large amount of medium-size magic stones.”
 
 My smug face, and Jack’s doubtful face.
 Duncan looked at me, rolling his eyes.
 
 “That contraption you were doing with Gramps… Is it usable?”
 
 “Satisfactorily.”
 
 “That’s nice.”
 
 “You’d better get some results from the development of this engine.”
 
 “Heh… bring it on.”
 
 Saying this, we exchanged electrifying gazes with challenging smiles.
 
 
 
 The thing Duncan and I were talking about was the 『Magic Power Recharger』.
 
 The device, which could be considered the advanced version of the magic stone stabilisation device, was something revolutionary that takes magic power from low-purity B-grade magic stones, which had up till now simply been thrown away, for refilling A-grade magic stones.
 
 An idea conceived by Joachim Ainsworth from two generations ago and completed by myself and my teacher^[4], the devices makes possible a mass supply of magic stones, which are a strategic resource.
 
 Truly a great invention that would change the world.
 That’s why we decided to keep it a secret for the time being. Of course, it’s being kept a secret from His Majesty as well.
 
 The only people who know the details about this device are myself and my teacher Godwin who created it, and Otou-sama.
 
 It is truly our 『trump card』.
 
 
 
 “Let’s get back to the discussion. We shall postpone the production of the real engines for a while.”
 
 Everyone nodded as I spoke.
 
 “We researched the special characteristics of the magic jet engine using the prototype engine made now, and can make an engine with better fuel efficiency. However, if we keep it at that we would take forever to lay the railroad, so I was thinking of doing the production of locomotive and passenger cars in parallel, but what does everyone think?”
 
 “No objections.”
 
 “No objections, I guess.”
 
 Jack replied immediately, and Duncan followed, nodding.
 None of the other craftsmen had any objections.
 
 “Then please proceed over the next two months with testing and production in mind. Duncan, please discuss the schedule with Sofia.”
 
 “Got it.”
 
 Thus the Cocomel Workshop proceeded with development aimed at the implementation of railroads.
 
 
 ☆
 
 
 “Sigh…”
 
 Dinner one day.
 Having come to the royal capital’s mansion in order to check the state of affairs of the Royal Capital Workshop, I unintentionally leaked a sigh.
 
 “What’s wrong, Letty. Is something troubling you?”
 
 As Otou-sama posed that question, I looked down at the tart in front of me.
 
 “It’s just that something 『isn’t going smoothly』.”
 
 “… Hmm. I’m not sure how much help I can be, but if it’s fine with you I can listen. Talking to someone can make gathering your thoughts easier.”
 
 “I guess. Well then,…”
 
 Then, I spewed out the problems I was facing almost like I was complaining to him.
 
 Since the photo studio is flourishing in the royal capital, I want to set up another store, but there isn’t enough human resources.
 
 The Royal Capital Workshop is working on energy-saving improvements for lifestyle magic tools, but it isn’t going as well as I hoped, and I can’t think of anything else to do.
 
 The magic jet engine isn’t improving at all.
 
 And, understanding the function and makeup of the black sphere seized during the monster grand invasion isn’t moving ahead at all.
 
 The sphere’s analysis in particular is in a complete deadlock.
 
 
 
 There’s no doubt that it is a magic tool.
 I could feel magic power inside so it most likely has a magic stone within.
 
 But we don’t know anything else.
 
 I tried physically poking it all over, but there was no response.
 
 If there was at least some kind of magic circuit running, I could feel the circuit structure like I did with the spider, but unfortunately there wasn’t.
 
 If I poorly try to flow magic power into it from the outside or dismantle it, it will probably explode or break.
 
 It’s a complete deadlock.
 
 
 
 “… I see. They’re all difficult issues, huh.”
 
 Having heard my complaints, Otou-sama rubbed his chin and said that.
 
 “Firstly, regarding the training of new personnel for the photo studio, we’ll probably just have to be patient as we increase it in small numbers. I too have had troubles in maintaining the knight order, but training people takes time.”
 
 “I guess so.”
 
 I guess the only way is to take the time training personnel, huh… Well, it can’t be helped.
 
 Otou-sama then continued speaking.
 
 “But the other problems are even more difficult. In any case, you and our craftsmen who are the best magic-toolsmiths in the country are at their wits’ end with this. Finding a solution won’t be so easy.”
 
 Then my father went 『Hm』 and pondered, then began mumbling.
 
 “Come to think of it, yes… no, but then Letty would… (mumble mumble mumble)”
 
 “?”
 
 I tilted my head.
 
 My father worried by himself for a while, and eventually took a good long look at me.
 
 “What’s wrong?”
 
 When I asked, with a worried expression upon Otou-sama’s face, he lightly patted me on the head and spoke.
 
 
 “Letty. Are you interested in 『Magic Academy』?”^[5]