Pathway to Japanese Literature

Dear readers, I trust you will recall the "Crimson Diamond" case handled by Toshihiko Tsukahara. When introducing that case, I mentioned to you all that he had a wealthy uncle; recently this same "Uncle Akasaka" expanded part of Tsukahara’s laboratory and installed there what we call a mercury quartz lamp. As for why Tsukahara requested this lamp—he had recently read a foreign criminology journal describing how mercury quartz lamps were being actively employed overseas for criminal investigations.

Therefore, Toshihiko, who was fond of research, made a request to Uncle Akasaka, whereupon the uncle promptly agreed and had the laboratory expanded and the equipment purchased and installed.

For some time, Toshihiko had wanted an X-ray apparatus, but had resigned himself to doing without due to its excessive complexity; however, since the mercury quartz lamp was a simpler device, he ultimately prevailed upon his uncle to acquire it.

Now, at this point, I think I should explain to you all what exactly a mercury quartz lamp is. The mercury quartz lamp, to put it simply, is a device that generates a type of light called ultraviolet rays. Therefore, I must go back further and explain what ultraviolet rays are.

I trust you are aware that sunlight is ordinarily composed of seven colors of light. Namely, these are red, orange, yellow, green, blue, indigo, and violet. When sunlight is analyzed through a spectroscope, it forms what is called a spectrum, separating into these beautiful colors. However, sunlight contains two additional types of invisible rays beyond these seven colors, which are commonly referred to as infrared and ultraviolet rays.

Infrared rays mean they lie outside the red portion of the spectrum, and ultraviolet rays mean they lie outside the violet portion.

Needless to say, light rays are a type of wave called light waves; as one progresses from the red toward the violet portion of the spectrum, their wavelengths gradually decrease while conversely their refractive power 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 lies in these chemical effects of ultraviolet rays. Consequently, a man named Finsen (1860-1904) sought to treat various illnesses by generating ultraviolet rays and ultimately invented what became known as the Finsen lamp. However, since the Finsen lamp's apparatus was somewhat elaborate, 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 brief, involves filling a vacuum quartz tube with mercury vapor and then causing it to emit light by passing direct current electricity through it. Thus mercury generates ultraviolet rays, and since quartz readily transmits ultraviolet rays, the device could be assembled quite simply. The direct current electricity required for ordinary quartz lamps typically ranged from approximately seventy to two hundred volts. In actual installation, though requiring measures like water cooling to prevent overheating of the quartz lamp, the entire apparatus remained extremely simple.

Now, mercury quartz lamps were ordinarily used for treating illnesses; however, they had recently come to be employed in scientific criminal investigations as well. In scientific criminal investigation, it was not the chemical effects of ultraviolet rays that were utilized, but rather primarily their physical effects. To explain what 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 manifestations: one where it glows while exposed to ultraviolet rays, and another where it continues glowing for some time even after the ultraviolet irradiation ceases.

And of these two, the latter—that is to say, substances that continue glowing for some time even after ceasing ultraviolet irradiation once it has been applied—were far more numerous. When we consider what substances glow under ultraviolet rays, it was many natural products. And thus, those that were artificial imitations of natural products did not glow. For example, human teeth glowed under ultraviolet rays, but dentures made from other substances did not. Furthermore, ivory and bone glowed under ultraviolet rays, but imitations made to resemble ivory did not. Furthermore, naturally occurring diamonds glowed under ultraviolet rays, but those made to imitate them with glass did not.

Therefore, if exposed to ultraviolet rays, the authenticity of diamonds could be immediately determined. Moreover, many aniline dyes emitted an extremely beautiful light when exposed to ultraviolet rays. Therefore, ultraviolet rays were also applied to the authentication of dyed goods and similar tasks.

Furthermore, by this same principle, one could authenticate paintings and calligraphy as well. Moreover, even grain powders would begin glowing when exposed to ultraviolet rays. When Toshihiko first had his uncle procure the mercury quartz lamp for him, he would shut himself daily in his laboratory—bringing various objects to expose them to ultraviolet rays, adjusting electrical current intensities for meticulous research—and systematically record every observation in his notebook.

He researched whatever he could get his hands on—human hair, animal fur, blood, urine, various paints, sealing wax used for letters, fabric fibers from clothing—and in some cases could distinguish them splendidly. Ecstatic with joy, Toshihiko shut himself away in his laboratory, forgetting even to eat or sleep, until after more than ten days he had become a veritable ultraviolet expert. “Brother, I really wish there would be some major case,” he said. “This time, I want to try using this ultraviolet light for detective work.”

One day—it was April—Toshihiko said to me.

“Well now—speaking of major cases—those thieves who targeted Ginza’s ×× jeweler still haven’t been caught yet, have they? How about it—couldn’t we solve that case with ultraviolet light?”

I said with a half-joking laugh. Ginza's ×× Jewelry Store was one of Tokyo's foremost establishments, and a necklace valued at ¥800,000 was stolen by thieves in a single night.

Although the police had been making considerable efforts, today—over two weeks later—they still had not only failed to apprehend the thieves but also had absolutely no idea where the necklace was. No clues whatsoever were discovered at the crime scene, and the safe had been destroyed with an acetylene torch, but it was confirmed that the burglars had indeed broken in from outside. Toshihiko also grinned upon hearing my words but immediately became serious again.

“I’ve been focusing all my efforts on ultraviolet research lately and had completely neglected studying criminal cases.” “You’re absolutely right, Brother. That case does sound intriguing.” “I think I’ll ask Uncle P how things have progressed since then.” “Brother, could you make a phone call for me?”

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

“Ah, we were just speaking of you.” I said. “Is that so?” Detective Oda grinned as he entered the room and took a seat facing Toshihiko. “Uncle P, what’s become of the Ginza jewelry case?” Toshihiko asked. Detective Oda’s expression darkened. “We’ve made little progress. Based on our investigations thus far, they don’t appear to be ordinary thieves prowling the area. They might even be individuals maintaining grand residences here in central Tokyo.”

"So right now we're searching under that policy, but it's not making much headway. But putting that aside—actually, last night a peculiar incident occurred, and I've come to seek your insight on the matter, Toshihiko."

Having said this, Detective Oda stared at Toshihiko’s face. Then Toshihiko's eyes suddenly began to shine.

“What is it?”

Toshihiko asked.

“Well actually, last night at Sudamachi’s tram stop, a man was struck by a tram and killed.” “The man was twenty-five or twenty-six years old and dressed in Western-style clothing, but aside from a coin purse and handkerchief found in his pockets, there was nothing else—no notebook or anything—leaving his identity completely unknown.” Since there were no names written on either his clothing or handkerchief, they had temporarily transported the body to the Metropolitan Police Department; however, even today his identity remains unknown. However, inside that coin purse were twelve yen and fifty-three sen in cash, along with a single sheet of black-colored paper.

The paper had text written in white paint, but its meaning remained utterly incomprehensible. “Even after the police racked their brains and couldn’t make sense of it, I came to ask you to read it, Toshihiko.”

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

The ¥800,000 Necklace Along with the black paper, Detective Oda produced yet another photograph.

“This shows Sudamachi where last night a man was run over—his death-face.”

he said.

Toshihiko gazed at the photograph for a while, then picked up the black paper. It was a sheet of black-dyed Japanese paper, on which the following characters had been written in white paint with a brush. yakashinu motsure kiteme hontori すけなをびえね tsumakeramasumu ちまとへよぼに ばりでのぶおす るくはてさたこ Toshihiko stared intently, but even he seemed unable to decipher it, furrowing his brow.

“How about it? Toshihiko. Even if you read it upside down, diagonally, or skip every other character—it still doesn’t make any sense!”

Toshihiko did not respond to that and continued his intense scrutiny, but soon stood up, “Please wait a moment.” As he said this, he entered the room containing the ultraviolet ray apparatus. The next instant, the distinctive sound of ultraviolet rays being employed reverberated.

After about seven minutes had passed, Toshihiko returned, his face radiant with delight. “Uncle P, I’ve deciphered it!” “What? You figured it out?” “What does it mean?” “It says this.”

With that, Toshihiko showed the pencil-written text in his notebook.

1-26 Hongō Ward Yushima Shinkamachi

Under the north window on the second floor

Detective Oda blinked rapidly in astonishment at the revelation.

“How on earth did you read those characters like this?” Detective Oda asked breathlessly.

Toshihiko smiled faintly and said, “Please come this way,” then led Detective Oda to the room containing the ultraviolet apparatus. I also followed them inside. Needless to say, this room had been constructed as a darkroom, and when Toshihiko turned off the electric lights, it became pitch-black. Then Toshihiko twisted the switch, and at that very moment, the mercury quartz lamp emitted a beautiful violet light.

Toshihiko placed the black paper fragment beneath it and illuminated it, but strangely, unrelated to the white characters, the aforementioned "Hongō..." text appeared glowing with fluorescence. “This was written on this black paper with aniline dye. “That’s why it can’t be seen under ordinary light. “However, when aniline dye is exposed to ultraviolet rays, it emits fluorescence like this.” said Toshihiko.

“Oh. So, these white characters were written to throw off anyone looking?”

Detective Oda let out a deep sigh and said.

“That’s right. So even if you read it upside down or diagonally, it doesn’t make any sense.”

We left the darkroom and returned once more to the reception room. "What on earth could this 'Hongō...' address notation mean?"

I asked Detective Oda. "Hmm, it might be the dead man's address."

Detective Oda tilted his head and answered. Then Toshihiko said, “In any case, let’s go visit this place right away.”

We immediately prepared, hired an automobile, and set off for Yushima Shinkamachi.

1-26 was a two-story house at the end of a quiet dead-end street, but to our surprise, a “For Rent” sign was affixed to the front latticework. When we inquired at the neighboring house, we learned this residence had long stood vacant—people claimed it was haunted, for at night one could sometimes hear sounds like footsteps.

However, since the landlord lived next door with one house in between, Detective Oda obtained permission, and we entered the vacant house. The front door wasn’t locked, and the interior of the house had been thoroughly ransacked.

Toshihiko strode up to the second floor. Toshihiko felt no fear whatsoever since he didn't believe in ghosts or such things. The second floor comprised two rooms - a six-mat space and a three-mat space - with a single window facing north in the three-mat chamber. "The 'north window' must refer to this one." Yet beneath that north window lay only tatami mats with nothing out of the ordinary. Toshihiko knelt down to survey the area thoroughly, but as might be expected, he found absolutely nothing.

“Brother, please lift the tatami mats.” After some time had passed, Toshihiko requested, so I lifted the tatami mats. At that moment, I exclaimed “Ah!” and nearly let the tatami mat slip from my hands. This was because, within the depression formed in the floorboards beneath those tatami mats, a diamond necklace lay coiled like a glittering serpent. We involuntarily exchanged glances.

Toshihiko picked up the necklace and handed it over to Detective Oda, “Does this ring any bells?” he asked. Detective Oda fiddled with it for some time, but eventually, “This seems to be the eight hundred thousand yen necklace stolen from Ginza’s ×× Jewelry Store.” he answered. “I see. Then let’s go to Ginza right away.”

With these words, Toshihiko promptly started down, so we too followed suit and left the house.

We boarded the waiting automobile and had it driven 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 serene afternoon sun was quietly shining down.

Before long, we arrived at Ginza’s ×× Jewelry Store. The portly, ruddy-faced proprietor, upon seeing Detective Oda’s face, immediately ushered us into a back room.

Detective Oda took the necklace out from his pocket and presented it before the proprietor.

“Ah!” With an admiring exclamation, the proprietor took it in his hands and examined it, but as he gazed 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 establishment,” he answered weakly. “What? A counterfeit? Then this is a fake?” Detective Oda asked, his eyes widening in surprise.

“That is correct. “In truth, this counterfeit was also produced at my establishment. “How on earth did you come by this?” Thereupon, Detective Oda briefly explained the sequence in which they had discovered it. And finally, he asked whose possession this counterfeit was in. According to the jeweler’s account, the necklace that had been stolen recently was in fact owned by Marchioness △△ of Azabu; however, due to certain circumstances, the jeweler had purchased it and, at the Marchioness’s request, created this counterfeit to deliver in place of the genuine article.

"In truth," added the proprietor, "we had kept this matter secret even from the police for Marchioness △△’s sake—but now that this counterfeit has come into police hands, maintaining secrecy might hinder the investigation instead. Therefore I shall disclose everything." We three then left the jeweler’s house and, taking the necklace with us, had the automobile driven further to Marchioness △△’s residence in Azabu. Marchioness △△’s residence appeared to be a compact house surrounded by a rather spacious garden.

Since we informed the butler that we had come from the Metropolitan Police Department, Marchioness △△ agreed to meet us directly. The Marchioness, wearing an extremely modest kimono, spoke pleasantly. After the greetings concluded, Detective Oda took out the necklace, “Would this not belong to your household?” he asked. “Good heavens!”

The Marchioness uttered a soft cry.

“How did this... This was stolen the day before yesterday.” “Where on earth was this found?”

“We found this in a rather strange place,” he explained, “but our investigation revealed it belongs to your household, hence our visit.” “How precisely was it stolen?” The Marchioness’s cheeks colored faintly as she replied: “You may already know this, but that necklace is a counterfeit.” “The student I had employed here—apparently mistaking it for genuine—stole it two days ago and fled.” “As for the real one, I need hardly mention—the piece recently stolen from ×× Jewelry Store is that.”

“About how old was that student?” “He said he was twenty-five.”

Detective Oda immediately took out a photograph of the deceased man from his pocket and showed it to the Marchioness upon hearing this. "Would this man be that student?" The Marchioness let out a gasp the moment she saw the photograph.

“This is him! This is him! This student is Murata.” “Why on earth did Murata die?” With hurried breath, the Marchioness inquired.

Daylight Murder

Detective Oda recounted to the Marchioness how Murata the student had been struck by a streetcar at Sudamachi Station and died, along with how the counterfeit necklace had been discovered. Finally he asked, "And when was Murata hired here?" "He joined us only on the tenth of this month."

Having heard this, Detective Oda turned to Toshihiko and said.

“So that’s five days after the burglary at Ginza’s ×× Jewelry Store.” Toshihiko had been silently listening to the conversation between Marchioness △△ and Detective Oda until now; at this moment he turned toward her.

“Through whose introduction was the student Murata employed?” Toshihiko asked.

“It was through an introduction from Dr. Kimura of Kōjimachi Fujimichō.” “When you say Dr. Kimura, do you mean that famous medical doctor—Director Kimura of Kimura Hospital?” “Yes, that’s correct. Whenever someone in our household falls ill, we always trouble Dr. Kimura.” Toshihiko smiled knowingly at this moment. That smile was one Toshihiko would let slip whenever he had gained some clue.

At that moment, the ringing bells of newspaper vendors distributing extras could be heard from the direction of the main street. Toshihiko briefly pricked up his ears but then continued speaking.

"Have you already informed Dr. Kimura about the student having fled?"

“No, I have not yet informed him.”

Then, Toshihiko said to Detective Oda.

“Then let us head to Kimura Hospital now.”

At that moment, the butler hurriedly entered holding an extra edition. "Madam! Something dreadful has occurred! Dr. Kimura was murdered!"

With a startled "What?!", the Marchioness leapt to her feet. Then, 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 located at ×-chōme, Fujimichō, Kōjimachi Ward, was stabbed in the heart by an unknown assailant in the hospital’s reception room around 2:00 PM today and died instantly. The aforementioned individual’s body was discovered by one of the nurses, but with the culprit’s identity remaining unknown, personnel from the Metropolitan Police Department—including Detective Shirai, police doctors, and the photography unit—rushed to the scene upon emergency notification to conduct a search, while a citywide cordon was established as they rigorously pursued the perpetrator. When Detective Oda finished reading the above extra edition article, Toshihiko—

“Uncle P, the case has finally grown complex, hasn’t it?” Toshihiko said. “What? So you think there’s a connection between Dr. Kimura’s death and the necklace incident?” “There certainly is!”

“Why?” “Well, I’ll explain that matter in detail later.” “Anyway, please obtain permission for me to investigate Dr. Kimura’s murder scene.” We took our leave from the Marchioness, left her residence after arranging for Detective Oda to keep custody of the counterfeit necklace until the case was resolved, had the car driven to the Metropolitan Police Department, secured permission from the Superintendent General through Oda’s efforts, and rushed to Kimura Hospital by dusk.

At Kimura Hospital’s reception room—that is, the scene of Dr. Kimura’s murder—Detective Shirai, now accompanied by another detective, was questioning the doctors and nurses. The police doctor had apparently already completed the autopsy, for Dr. Kimura’s corpse lay upon the reception room table, covered with a white cloth.

Detective Shirai looked at Toshihiko’s face and smiled sarcastically. Ever since the "Mustache Mystery" incident, he had conceded a step to Toshihiko, but now his face clearly showed a determination not to lose to him this time. However, Toshihiko greeted them with complete innocence and fixed his eyes on the old frame hanging at the front of the reception room,

“Is this Dr. Kimura’s portrait?”

Toshihiko asked. When the nurse nodded, Toshihiko stared intently at the nearly life-sized bust photograph, then drew back the white cloth, bowed once, and examined Dr. Kimura’s corpse. Starting with the face, he carefully observed the entire body and inspected the wound in the cardiac region. Everyone silently watched Toshihiko’s actions. Finally—for reasons unclear—Toshihiko began intently comparing the corpse’s face with that in the photograph, but before long turned to Detective Shirai and—

“Is this truly Dr. Kimura’s corpse?” Toshihiko asked.

All of us were startled by this unexpected question. Detective Shirai, too, made a dumbfounded face at this absurdity,

“Toshihiko, you shouldn’t be making jokes like this. We have to find the culprit as quickly as possible, so we can’t afford to entertain such questions.” “I see. But unless we determine whether this is Dr. Kimura’s corpse or not, we shouldn’t be able to identify the culprit.” “What a strange thing to say. The nurses were with this Dr. Kimura until just this morning, and after all, comparing it with the photograph should make it clear, shouldn’t it?” Toshihiko turned to the nurse standing beside him,

“Excuse me, could you please bring me some alcohol-soaked cotton?”

he requested.

When the nurse brought alcohol-soaked cotton, Toshihiko received it and wiped over the beauty mark on the right cheek of the corpse's face.

Then something astonishing happened. As Toshihiko wiped several times, the beauty mark vanished, leaving black residue on the cotton. Everyone gasped in shock. At that moment, Toshihiko declared triumphantly,

“Everyone, this isn’t Dr. Kimura who was killed here—it’s likely his twin brother.”

Toshihiko said.

And then, you can probably imagine just how much of a commotion everyone began to make.

Detective Shirai was momentarily stunned, but if the corpse's beauty mark had been artificial, then Toshihiko's hypothesis would be 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 for about two months. However, Dr. Kimura was unmarried and had no parents, so no one knew he had a twin brother.

“Then the real Dr. Kimura was probably killed about two months ago, and this person had become his body double,” Toshihiko said. Then Toshihiko turned to Detective Oda and,

“The case has grown increasingly complex indeed, but I believe everything will be resolved very soon.”

Having said that, he turned to face the nurses.

“There’s an ultraviolet treatment room in this hospital, isn’t there?” “Please guide me to that room.”

Toshihiko said.

Guided by the nurses, we went to the ultraviolet treatment room. There stood a mercury quartz lamp like the one Toshihiko carried, with a single bed placed at the center and medicine cabinets alongside bookshelves installed along one wall.

Toshihiko was examining each of these items one by one when he took out a notebook from the bookshelf. It was bound in black Japanese paper, and though opening it revealed nothing written inside, when Toshihiko lit the mercury quartz lamp and shone it upon the pages, characters emitting fluorescence appeared on the paper.

“It’s a diary.” Having said this to no one in particular, Toshihiko eagerly leafed through each page and read.

After taking about thirty minutes to finish reading the diary, he turned to the nurse and—

“Did Director Tanaka of Hongō Hospital come here today?”

he asked.

“Yes, he came a little past noon and seemed to have left almost immediately.” Upon hearing this, Toshihiko turned to Detective Shirai and said, “Please arrest Director Tanaka immediately.”

Dear readers, Director Tanaka, who had been arrested, was indeed the culprit who killed Dr. Kimura’s body double. And thus, through that confession, all circumstances became clear. Dr. Kimura’s body double was, as Toshihiko had deduced, the doctor’s twin brother.

Though they were brothers, he was a villain of entirely different character from the doctor—from his youth, he had gone to China and indulged in wicked deeds freely, befriended Director Tanaka, and together they wreaked havoc around Shanghai; three months earlier, the two had come to Tokyo to plan a major crime. Though neither of them were doctors, they resolved to become physicians and wreak havoc in the capital. First, Tanaka established Tanaka Hospital in Hongō, befriended Dr. Kimura, and observed Dr. Kimura’s mannerisms—relaying these observations to his twin brother. One night, he lured Dr. Kimura to his home and murdered him, treated the corpse with chemicals, then sent his twin brother back as a substitute.

While under an arrangement to repay this favor by raiding jewelers, stealing gems, and delivering them to Tanaka, the body double Kimura discovered the existence of a necklace at a Ginza jeweler and skillfully stole it the other day. However, Kimura came to want the necklace for himself and, even when Tanaka demanded it, made excuses and refused to hand it over. Tanaka made various threats, but eventually Kimura happened to discover that a counterfeit necklace was at the Marchioness △△’s residence in Azabu. Taking advantage of the Marchioness’s household being one of Dr. Kimura’s patient homes, he had his trusted subordinate Murata take up residence there as a live-in student and ultimately made him steal it. Then he had the counterfeit hidden in the vacant house in Yushima Shinkamachi and attempted to have Murata deliver that black paper fragment to Tanaka.

Though they could have simply had Murata directly hand over the counterfeit, during their time in Shanghai they had employed a method where one would steal and hide items in vacant houses while the other retrieved them through coded communications—carrying this out out of habit. Moreover, among their criminal associates there existed a superstition that proceeding in such a manner somehow felt safer. However, Murata met an unexpected calamity and died an unnatural death, rendering him unable to deliver Kimura’s communication to Tanaka. Consequently, Tanaka came to negotiate with Kimura—and as a result killed him. The necklace stolen from the aforementioned Ginza jeweler was found in Kimura Hospital’s safe.

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

“Those who need ultraviolet light to read communications would possess a mercury quartz lamp,” he explained. “I reasoned that mercury quartz lamp owners would most likely be medical professionals. This made me suspect Dr. Kimura initially—though it seemed odd for him to be a thief—but when I examined the corpse and confirmed the beauty mark was artificial, I realized it had to be a body double.” He concluded decisively: “And since that diary contained full details, everything fell into place at once.”