Pathway to Japanese Literature

"Dear readers, I believe you will recall the 'Crimson Diamond' case handled by Tsukahara Toshio-kun." When introducing that case, I had mentioned to Toshio-kun that he had a wealthy uncle, but recently Toshio-kun had this "Uncle in Akasaka" expand part of his laboratory and purchase and install a mercury quartz lamp there.

As for why Toshio-kun had the mercury quartz lamp purchased, it was because he had recently read a foreign criminology magazine and learned that mercury quartz lamps were increasingly being employed in criminal investigations abroad these days. Therefore, Toshio-kun, who loved research, made a request to the uncle in Akasaka, whereupon the uncle promptly agreed and expanded the laboratory while purchasing and installing the apparatus.

For some time, Toshio-kun had wanted an X-ray apparatus, but he had held back because it would have been too elaborate; however, since the mercury quartz lamp was a simple device, he finally pestered his uncle into getting it. Now, I shall explain to you all what a mercury quartz lamp is. The mercury quartz lamp, to put it plainly, is a device that produces a type of light known as ultraviolet rays. Therefore, I must go back further and explain what ultraviolet rays are.

You all likely know that sunlight is ordinarily composed of seven colors of rays. Namely, these are red, orange, yellow, green, blue, indigo, and violet; when sunlight rays are analyzed through a spectroscope, they form what is called a spectrum and separate into these beautiful colors. However, sunlight rays contain two additional types of invisible light beyond these seven colors, which are commonly referred to as infrared rays and ultraviolet rays.

The term "infrared rays" means they are positioned outside the red of the spectrum, and "ultraviolet rays" means they are positioned outside the violet of the spectrum.

Needless to say, light rays are a type of wave called light waves; from the red end toward the violet end of the spectrum, their wavelengths gradually decrease while their refractive power conversely increases. Thus, the rays on the red side possess thermal effects, and those on the violet side possess chemical effects. Therefore, infrared rays are richest in thermal effects, and ultraviolet rays are richest in chemical effects.

The reason sunlight promotes human health is because of the chemical effects of these ultraviolet rays. Therefore, a man named Finsen (1860–1904) sought to cure various illnesses by generating ultraviolet rays and invented what is known as the Finsen lamp. However, since this so-called Finsen lamp had a somewhat elaborate setup, a man named Kromayer later devised a simpler device for generating ultraviolet rays. That is none other than the mercury quartz lamp.

The mercury quartz lamp, to explain its principle in a nutshell, involved filling a vacuum-sealed quartz tube with mercury vapor and causing it to emit light by passing a direct electric current through it. In this way, mercury generated ultraviolet rays, and quartz allowed ultraviolet rays to pass through well, making the device quite simple to construct. The direct current required for a typical quartz lamp was approximately 70 to 200 volts. When actually installing it, one needed to cool the quartz lamp with water to prevent overheating, but the entire setup remained extremely straightforward.

Now, mercury quartz lamps were typically used for the purpose of treating illnesses, but they had recently come to be used in scientific criminal investigations as well. Thus, in scientific criminal investigations, it was not the chemical effects of ultraviolet rays but primarily their physical effects that were applied. To explain what kind of physical effects ultraviolet rays possess, when ultraviolet rays strike many substances, they cause them to emit a phosphorescent-like light. This phosphorescent-like light has two cases: one where it emits light while ultraviolet rays are applied, and another where it continues emitting light for a while even after the ultraviolet rays are stopped.

And of these two cases, the latter—that is, once ultraviolet rays were applied, even after ceasing to expose them, there were far more substances that continued to emit light for some time. When it came to what glowed under ultraviolet rays, many natural products fell into this category. And those artificial imitations of natural products did not glow.

For example, human teeth glowed when exposed to ultraviolet rays, but dentures made from other materials did not. Similarly, ivory and bone emitted light under ultraviolet rays, but imitations crafted to resemble ivory remained dark. Natural diamonds shone when subjected to ultraviolet rays, while glass counterfeits designed to mimic them showed no luminescence. Therefore, through ultraviolet exposure, diamond authenticity could be immediately determined.

Moreover, many aniline dyes emit an extremely beautiful light when exposed to ultraviolet rays. Therefore, ultraviolet rays are also applied to the appraisal of dyed goods, among other things. Furthermore, by the same principle, one can also authenticate the genuineness of calligraphic works and paintings. In addition, even grain powders and the like begin to glow when exposed to ultraviolet rays. In the days immediately after his uncle had purchased the mercury quartz lamp for him, Tsukahara Toshio would seclude himself in the laboratory every day, bringing in various objects to expose them to ultraviolet rays, adjust the current strength in different ways to conduct thorough research, and meticulously record each finding in his notebook.

He researched whatever came to hand—human hairs, animal furs, blood, urine, various paints, sealing wax used for letters, clothing fibers—and in some cases could distinguish them with remarkable precision. Delighted beyond measure, Toshio-kun shut himself away in the laboratory, forgetting even to eat or sleep, until within ten-odd days he had become a veritable ultraviolet expert. “Bro, I sure wish a major case would come our way. This time, I want to use these ultraviolet rays to try out some detective work!”

One day—it was in April—Toshio-kun said to me. “Well, speaking of major cases—the thieves who targeted the Ginza △△ Jeweler lately still haven’t been arrested, have they? What do you think—couldn’t that case be solved with ultraviolet rays?” I said with a half-joking laugh. The Ginza △△ Jeweler was one of Tokyo’s foremost major stores, and a necklace valued at 800,000 yen had been stolen by thieves in a single night.

The police had been conducting an intense investigation, but even after over two weeks had passed since then, they remained completely clueless not only about the thieves' whereabouts but also regarding where exactly the necklace might be. No clues had been discovered at the crime scene either—the safe had been destroyed with an acetylene torch—though it was certain that intruders had broken in from outside. Toshio-kun smiled warmly at my words but immediately turned serious again.

“Lately I’ve been devoting myself entirely to ultraviolet research and neglecting criminal case investigations.” “You’re right, Bro—that case does sound intriguing.” “Maybe I should ask Uncle P about how it’s progressing.” “Bro, could you make a phone call for me?”

As I started to stand up, just then there came a sound of knocking on the laboratory door. When I opened it, to my surprise, the visitor was none other than “Uncle P”—Detective Oda of the Metropolitan Police Department.

“Oh, we were just talking about you!” I said. “Is that so?” Detective Oda smiled warmly as he entered and sat facing Toshio-kun. “Uncle P, how is the Ginza jewelry case coming along?” Toshio-kun asked. Detective Oda’s face clouded over. “We still have absolutely no leads.” “Well, based on what we’ve uncovered so far, they don’t seem to be your average thieves prowling the area.” “They might even be someone who has built a grand residence right here in central Tokyo.”

“So right now we’re searching based on that approach, but it’s not progressing well. —Well, putting that aside, actually, a strange incident occurred last night, and I’ve come to seek your insight on the matter, Toshio-kun.” Having said this, Detective Oda stared intently at Toshio-kun’s face. Then Toshio-kun’s eyes suddenly lit up. “What is it?” Toshio-kun asked.

“Well, you see—last night at Sudamachi tram station, a man was struck by a train and died.” “The man was twenty-five or twenty-six years old and dressed in Western-style clothing, but in his pockets were found only a drawstring purse and a handkerchief; there was no notebook or anything else, so his identity remains completely unknown.” Since there were no names written on either the clothes or the handkerchief, they transported the body to the Metropolitan Police Department for the time being; however, even today, his identity remains unknown. However, inside the drawstring purse were twelve yen and fifty-three sen in cash, along with a single sheet of black-colored paper.

“The paper had phrases written in white pigment, but their meaning remained undecipherable no matter what we tried. Since even our police experts couldn’t crack it after racking their brains raw, I thought I’d come ask you to take a look, Toshio-kun.”

Having said this, Detective Oda took out a single sheet of black paper from his pocket. It was a sheet of paper approximately nine centimeters square. The 800,000 Yen Necklace

Detective Oda took out a photograph along with the black paper. “This is the face of the man who was run over last night in Sudamachi.”

Detective Oda said. Toshio-kun gazed at the photograph for a while, then picked up the black paper. It was Japanese paper dyed black, on which the following characters had been written in white pigment with a brush. やかしぬもつれ きためほんとり すけなをびえね つまけらますむ

ちまとへよぼに ばりでのぶおす るくはてさたこ Toshio-kun was staring intently, but even he seemed unable to make sense of it, furrowing his brow. “How about it? “Toshio-kun.” “Even if you read it upside down, diagonally, or every other character, it makes no sense at all, does it?”

Toshio-kun did not respond and continued his research intently, but before long, he stood up and— “Please wait a moment.” As he said this, he entered the room with the ultraviolet device. The next moment came the peculiar sound of ultraviolet rays being used.

After about seven minutes had passed, Toshio-kun returned, his face shining with a cheerful glow. “Uncle P, I’ve deciphered it!” “Huh? You figured it out? What does it mean?” “This is what it says.” With that, Toshio-kun showed the pencil-written characters in his notebook. Hongō-ku, Yushima Shinhana-chō 26-banchi no 1

Beneath the north window on the second floor. Detective Oda blinked rapidly in astonishment at the sheer unexpectedness of it all. “How on earth can you read those characters like this?” he asked breathlessly.

Toshio-kun smiled warmly and said, “Please come this way,” then led Detective Oda to the room containing the ultraviolet device. I also followed them inside. Needless to say, this room was designed as a darkroom, and when Toshio-kun turned off the electric lights, everything became pitch black. Then Toshio-kun twisted the switch, whereupon the mercury quartz lamp emitted a beautiful purple light. Toshio-kun placed the black paper fragment beneath it and illuminated it. Strangely enough, completely unrelated to the white characters, the aforementioned “Hongō...” text fluoresced into visibility.

“This was written on this black paper with aniline dye. That’s why it isn’t visible under normal light. However, when aniline dye is exposed to ultraviolet rays, it emits fluorescence like this.” Toshio-kun said.

“Oh.” “So these white characters were meant to mislead people?”

Detective Oda let out a deep sigh and said. “That’s right. That’s why it makes no sense even if you read it upside down or diagonally.”

We exited the darkroom and returned to the reception room. "What on earth is this 'Hongō...' address referring to?" I asked Detective Oda. "Hmm, maybe it's the dead man's address."

Detective Oda tilted his head and answered. Then Toshio-kun— “Anyway， why don’t we go check out this place right now?”

Toshio-kun said. We immediately prepared ourselves, hired a car, and set off for Yushima Shinhana-chō. 26-1 was a two-story house at the end of a quiet backstreet, but to our surprise, a "For Rent" sign was posted on the front lattice. When we inquired at the neighboring house, we learned that this house was said to be haunted because sounds resembling people walking could sometimes be heard at night, and as a result, it had remained unrented for a long time.

However, since the landlord was one house over next door, Detective Oda went to obtain permission, and we entered the vacant house. The front door wasn’t locked, and the interior of the house had been thoroughly ransacked. Toshio-kun strode briskly up to the second floor. Toshio-kun wasn’t scared at all because he didn’t believe in things like monsters.

The second floor consisted of two rooms—a six-tatami space and a three-tatami one—with a single window facing north in the three-tatami room. "The 'north window' referred to must be that one." However, beneath that north window, there were only tatami mats and nothing unusual. Toshio-kun knelt down and scanned the area thoroughly, but as expected, he could find nothing of note.

“Brother, please lift up the tatami mats.” After Toshio-kun made this request a short while later, I lifted the tatami mats. And at that moment, I exclaimed “Ah!” and nearly let the tatami mat slip from my hands. This was because, in the depression formed in the floorboard beneath the tatami, lay coiled a diamond necklace like a glittering snake. We involuntarily exchanged glances.

Toshio-kun picked up the necklace and handed it to Detective Oda, “Well? Does this look familiar to you?”

Toshio-kun asked. Detective Oda fiddled with it for a while, but soon— “It seems this is the aforementioned 800,000 yen necklace that was stolen from Ginza’s ×× Jewelry Store.” Detective Oda answered. “I see. Then let’s head to Ginza right away.” After saying this, Toshio-kun started briskly descending, so we followed and left the house.

We boarded the automobile we had kept waiting and set off toward Ginza. In the gardens of the houses passing by on both sides, late-blooming cherry blossoms were beautifully blooming here and there, and the bright afternoon sun was quietly shining over everything.

Before long, we arrived at the XX Jewelry Store in Ginza. The portly, red-faced proprietor, upon seeing Detective Oda’s face, promptly ushered us into a back room. Detective Oda took out the necklace from his pocket and presented it before the proprietor. “Ah!” he exclaimed in admiration as he took it in his hands, but after gazing at it for a while, a look of disappointment appeared on his face. “This is a counterfeit of the necklace that was stolen from my house.”

the proprietor answered weakly. “Huh? A counterfeit? Then it’s a fake?” Detective Oda asked with widened eyes. “That is correct. In fact, I had this counterfeit made at my establishment. How on earth did you come by this?”

Then Detective Oda briefly explained how this had been discovered. Then finally he asked who owned this counterfeit. According to the jeweler’s account, the necklace stolen days earlier had actually belonged to Marquise △△ of Azabu; however, due to certain circumstances he had purchased it and created a counterfeit at her request to deliver in place of the genuine article. “In truth we’d kept this secret from the police for Her Ladyship’s sake,” added the proprietor, “but now that you’ve found this replica, hiding facts would only hamper your investigation. That’s why I’m telling you everything.”

The three of us then left the jeweler’s house and, taking the necklace with us, had the automobile drive further to Marquise △△’s residence in Azabu. Marquise △△’s residence appeared to be a modest house, surrounded by a rather spacious garden.

Since we informed the butler that we had come from the Metropolitan Police Department, Marquise △△ agreed to meet us directly. The Marquise, wearing a plain kimono, spoke pleasantly. After the greetings concluded, Detective Oda took out the necklace and asked, “Isn’t this your belonging, Madam?”

“Oh my!”

The Marquise let out a light scream.

“How did this… This was stolen the day before yesterday.” “Where on earth was it?” “We found it in a rather peculiar place during our investigation, and having confirmed it belongs to your residence, we’ve come to inquire.” “Might I ask precisely how it was stolen?”

The Marquise’s face flushed red in an instant as she said, “That necklace—you may already be aware—is a counterfeit.” “However, the student I had employed at my house—perhaps believing it to be genuine—stole it the day before yesterday and fled.” “As for the genuine one, I need not mention it further, but it was recently stolen from the XX Jewelry Store.” “About how old was that student?”

“He said he was twenty-five.”

Upon hearing that, Detective Oda took out a photo of the dead man from his pocket and showed it to the Marquise.

“Isn’t this man that student?” As soon as the Marquise saw the photo, she exclaimed, “Ah!”

“Oh, this is him, this is him! This is Murata, the student.” “How on earth did Murata die?” the Marquise asked with hurried breath.

Murder in Broad Daylight Detective Oda recounted to the Marquise how Murata the student had been struck by a tram at Sudacho Station and died, along with the circumstances surrounding the counterfeit necklace's discovery, then finally inquired, "And when was Murata employed here?" Detective Oda asked. "He only began service on the tenth of this month."

Upon hearing this, Detective Oda turned to Toshio and said.

“So, this was five days after the burglary at the Ginza XX Jewelry Store.”

Toshio, who had been silently listening to the conversation between Marquise △△ and Detective Oda until now, turned to the Marquise and asked, “Through whose introduction was that student Murata employed?” “It was through an introduction from Dr. Kimura of Fujimichō, Kōjimachi.” “When you say ‘Dr. Kimura,’ do you mean that renowned medical scholar—Director Kimura of Kimura Hospital?”

“Yes, Dr. Kimura always assists us when someone in our household falls ill.” Toshio-kun smiled knowingly at whatever thought had crossed his mind at that moment. That smile was one he would let out whenever he gained some clue. At that moment, the jingling of a bell from an extra edition distributor could be heard coming from the direction of the main street. Toshio-kun briefly strained his ears but then continued speaking.

“Have you already informed Dr. Kimura about the student’s fleeing?” “No, I haven’t told him yet.” Then, Toshio-kun turned to Detective Oda and said.

“Then, let’s go to Kimura Hospital now.”

At this moment, the butler hurriedly entered holding a copy of the extra edition.

“Madam, something terrible has happened!” “It seems Dr. Kimura has been killed.”

“What?!” exclaimed the Marquise △△, leaping to her feet. After hurriedly reading the extra edition the butler had handed over, she passed it wordlessly to Detective Oda.

Director Kimura of Kimura Hospital Murdered in Broad Daylight

Dr. Kimura Teiichi (42), Director of Kimura Hospital and Medical Scholar of Fujimichō, Kōjimachi Ward, was stabbed in the heart by an unknown assailant in the reception room of the same hospital at approximately 2:00 p.m. today and died instantly. The deceased’s body was discovered by one of the nurses, but with the culprit’s identity remaining unknown, Detective Shirai—alongside a police doctor, photography unit, and others from the Metropolitan Police Department—rushed to the scene upon receiving the urgent report and commenced their search. Meanwhile, police cordons were set up across the city as authorities rigorously pursued the perpetrator.

When Detective Oda finished reading the above extra edition article, Toshio-kun said,

“Uncle P, the case has truly become complicated now, hasn’t it?”

he said. “Huh? So you think Dr. Kimura’s death is related to the necklace case?” “There certainly is!”

“Why?” “Well, I’ll explain that in detail later. Anyway, please obtain permission for me to investigate Dr. Kimura’s murder scene.” We took our leave from the Marquise, left her residence after entrusting the counterfeit necklace case to Detective Oda’s custody until its resolution, had the car driven to Metropolitan Police Headquarters, obtained permission from the Superintendent General through Detective Oda’s efforts, and rushed to Kimura Hospital as dusk fell.

At Kimura Hospital’s reception room—the scene of Dr. Kimura’s murder—Detective Shirai was now there with another detective, the two of them questioning the medical staff and nurses. The police doctor had apparently already completed the autopsy, and Dr. Kimura’s corpse was laid out on the reception room table, covered with a white cloth. Detective Shirai looked at Toshio-kun’s face and smiled sarcastically. Ever since the "Beard Mystery" incident, he had been conceding a step to Toshio-kun, but this time, a resolve not to lose to him was clearly visible on his face. However, Toshio-kun greeted them utterly innocently and fixed his eyes on the old-fashioned frame hanging on the front wall of the reception room,

“Is this a portrait of Dr. Kimura?” he asked. When the nurse nodded, Toshio-kun stared intently at the nearly life-sized bust photograph, then draped a white cloth over it and bowed once before examining Dr. Kimura’s corpse. Starting with the face, he thoroughly observed the entire body and re-examined the wound in the heart area. Everyone silently watched Toshio-kun’s actions. Finally, Toshio-kun kept intently comparing the corpse’s face with the one in the photograph, but eventually turned toward Detective Shirai and,

“Is this truly Dr. Kimura’s corpse?” he asked. Our entire group was surprised by this unexpected question. Detective Shirai also wore a look of astonishment at the sheer absurdity of it all— “Toshio-kun, you shouldn’t joke about this. We have to find the culprit as soon as possible, so I can’t entertain such questions.”

“I see. However, unless we determine whether this is Dr. Kimura’s corpse or not, we shouldn’t be able to identify the culprit.” “You’re saying something strange. The nurses were with Dr. Kimura until this morning, and besides, comparing it to the photo should make it clear.” Toshio-kun turned to a nurse standing nearby and said, “Excuse me, could you please bring some absorbent cotton soaked in alcohol?” When the nurse brought the alcohol-soaked cotton, Toshio-kun took it and wiped the mole on the right cheek of the corpse’s face.

Then, lo and behold! When Toshio-kun wiped it several times, the mole disappeared, leaving black residue on the cotton. Everyone gasped in astonishment. At that moment, Toshio-kun said triumphantly, “Everyone, the one who was killed is not the real Dr. Kimura.” “Probably Dr. Kimura’s twin brother.”

he said.

And then, you can all imagine just how much of an uproar everyone caused. Detective Shirai was momentarily stunned, but since the mole on the corpse being fake meant Toshio-kun’s hypothesis was correct, when he questioned the nurses and medical staff about the circumstances, they all uniformly stated that the doctor’s demeanor had seemed slightly different from before starting around two months prior. However, Dr. Kimura was single, had no parents, and no one knew he had a twin brother.

“Then, the real Dr. Kimura was likely killed about two months ago, and this person must have been acting as his substitute,” said Toshio-kun. Then Toshio-kun turned to Detective Oda and,

“The case has become more and more complicated, but I think everything will be resolved very soon.”

Having said this, he then turned to the nurse and, “There’s an ultraviolet treatment room in this hospital, isn’t there?” “Please guide me to that room.”

“Please guide me to that room,” he said.

Under the nurse’s guidance, we went to the ultraviolet treatment room. There was a mercury quartz lamp like the one Toshio-kun possessed, a single bed was placed at the center, and one wall was equipped with medicine shelves and bookshelves. Toshio-kun examined each item one by one, and before long, he pulled out a notebook from the bookshelf. It was a volume bound in black Japanese paper, and though nothing was written inside when opened, when Toshio-kun lit the mercury quartz lamp and shone it on the pages, text glowing with fluorescence appeared.

“It’s a diary!” To no one in particular, Toshio-kun said this and eagerly flipped through each page as he read.

After spending about thirty minutes finishing reading the diary, he turned to the nurse and, “Today, Director Tanaka from Hongo Hospital came by, didn’t he?”

he asked. “Yes, he came by a little past noon and seemed to leave right away.”

Upon hearing that, Toshio-kun turned toward Detective Shirai and, “Please arrest Director Tanaka immediately.”

“... ,” he said.

Dear readers, Director Tanaka, who had been arrested, was indeed the culprit who killed Dr. Kimura’s body double. And through that confession, all the details of the case came to light. Dr. Kimura’s body double was, as Toshio-kun had deduced, the doctor’s twin brother. Though he was Dr. Kimura’s brother, this villain had a completely different personality from the doctor. From his youth, he had gone to China where he indulged in all manner of wicked deeds, became friends with Director Tanaka, and the two of them roamed around Shanghai wreaking havoc. Three months prior, they had come to Tokyo and plotted a grand crime.

Neither of them were doctors, but they resolved to become physicians to wreak havoc in the capital. First, Tanaka built Tanaka Hospital in Hongo, associated with Dr. Kimura, observed Dr. Kimura’s behavior, informed his twin brother of these observations, lured Dr. Kimura to his home one night and murdered him, treated the corpse with chemicals, and sent the twin back as a substitute in his place.

The body double Kimura, in return for this favor, had promised to raid a jewelry store, steal gems, and deliver them to Tanaka. In the course of this arrangement, he discovered the existence of a necklace at Ginza’s ×× Jewelry Store and skillfully stole it just the other day. However, Kimura came to want the necklace for himself and made excuses when Tanaka demanded its return, refusing to hand it over. Tanaka made various threats, but eventually, Kimura happened to discover that a counterfeit necklace was at Marquise △△’s residence in Azabu. Taking advantage of the fact that the marquise’s household was one of Dr. Kimura’s patients, he had his trusted subordinate Murata infiltrate the residence as a live-in student and ultimately steal it. He then had the counterfeit hidden in a vacant house in Yushima Shinkamachi and tried to have Murata deliver that black piece of paper to Tanaka.

Though they could have simply had Murata hand over the counterfeit directly, back when they were in Shanghai, the two had employed coded communications—one would steal and hide items in vacant houses while the other retrieved them—and so they habitually followed that method here. Moreover, there was a kind of superstition among the criminal associates, and they thought that doing it that way felt somewhat safer. However, due to an unforeseen calamity, Murata met an unnatural death and was unable to deliver Kimura’s message to Tanaka. As a result, Tanaka came to confront Kimura, which ended in Tanaka killing him. The necklace stolen from the ×× Jewelry Store was found in the safe at Kimura Hospital.

A few days after the case had been resolved, Detective Oda came to visit us and asked how Toshio-kun had deduced that Dr. Kimura’s death was connected to the necklace incident. Toshio-kun then answered as follows.

“Those who need to read communications with ultraviolet rays would possess a mercury quartz lamp.” “I reasoned that mercury quartz lamp owners would most likely be doctors.” “So I suspected Dr. Kimura, but since it seemed odd for Dr. Kimura to act as a thief, when I examined the corpse and confirmed the mole was fake, I realized it was a body double.” “And since that diary contained detailed records, everything was resolved at once.”