In Japanese mythology, the two tide jewels, named and , were magical gems that the Sea God used to control the tides.
The earliest texts record an ancient myth that the presented the tide jewels to his son-in-law Hoori aka Yamasachihiko (Prince Luck-of-the-Mountain).
Later Japanese writings refers to the tide jewels as being in the possession of the or Dragon King or being housed in his , where the myth of the loan of these jewels became attached to the conquest of Korea by Empress Jingū.
Terminology and are the full, archaic "tide jewel" names, prefixed with ; they are also called shio-tama and mitsu-tama respectively, for short.
The short names can be possibly be read as and in on'yomi or Sino-Japanese reading.
Early references Two Nara period (710–794 CE) historical texts record myths that the Sea God presented the kanju and manju to Hoori, and a Kamakura period (1192–1333 CE) text says the legendary Empress Jingū used the tide jewels to conquer a Korean kingdom in 200 CE.
The tide jewels are central to "The Lost Fishhook" legend about the fisherman Hoderi and hunter Hoori, two brothers who argued over replacing a lost fishhook. Hoori went searching to the bottom of the sea, where he met and married Toyotama-hime, the daughter of the dragon Sea God. After living three years in the undersea Ryūgū-jō 竜宮城 "dragon palace castle", Ryūjin presented Hoori with his brother's fishhook and the tide jewels, and arranged for him to take his sea-dragon bride back to land.
Kojiki The c. 680 CE Kojiki 古事記 "Record of Ancient Matters" uses the archaic names shiomitsu-tama 潮満珠 "tide-flowing jewel" and shiohiru-tama 潮干珠 "tide-ebbing jewel" in two consecutive passages.
The first describes the sea-god's advice to Hoori about how to confront his duplicitous brother Hoderi. "What thou shalt say when thou grantest this fish-hook to thine elder brother [is as follows]: 'This fish-hook is a big hook, an eager hook, a poor hook, a silly hook.' Having [thus] spoken, bestow it with thy back hand. Having done thus, – if thine elder brother make high fields, do Thine Augustness make low fields; and if thine elder brother make low fields, do Thine Augustness make high fields. If thou do thus, thine elder brother will certainly be impoverished in the space of three years, owing to my ruling the water. If thine elder brother, incensed at thy doing thus, should attack thee, put forth the tide-flowing jewel to drown him. If he express grief, put forth the tide-ebbing jewel to let him live. Thus shalt thou harass him." With these words, [the Sea-Deity] gave [to His Augustness Fire-Subside] the tide-flowing jewel and the tide-ebbing jewel, – two in all, – and forthwith summoned together all the crocodiles, and asked them, saying: "The Sky's-Sun-Height, august child of the Heaven's-Sun-Height, is now about to proceed out to the Upper-Land. Who will in how many days respectfully escort him, and bring back a report?" So each according to the length of his body in fathoms spoke, fixing [a certain number of] days, – one of them, a crocodile one fathom [long], saying: "I will escort him, and come back in one day." So then [the Sea-Deity] said to the crocodile one fathom [long]: "If that be so, do thou respectfully escort him. While crossing the middle of the sea, do not alarm him!" Forthwith he seated him upon the crocodile's head, and saw him off. So [the crocodile] respectfully escorted him home in one day, as he had promised. This "crocodile" translates , a legendary Japanese dragon and sea-monster also translated as "shark". At the end of Toyotama-hime's pregnancy, she asks Hoori not to look at her during childbirth (hinting at shapeshifting), but he looks and sees her true shape of a dragon (Kojiki) or a wani (Nihongi).
The subsequent passage describes Hoori using the tide jewels to force his brother's submission. Hereupon [His Augustness Fire-Subside] gave the fish-hook [to his elder brother], exactly according to the Sea-Deity's words of instruction. So thenceforward [the elder brother] became poorer, and poorer, and, with renewed savage intentions, came to attack him. When he was about to attack [His Augustness Fire-Subside, the latter] put forth the tide-flowing jewel to drown him; on his expressing grief, he put forth the tide-ebbing jewel to save him. When he had thus been harassed, he bowed his head, saying: "I henceforward will be Thine Augustness's guard by day and night, and respectfully serve thee."
Nihongi The c. 720 CE Nihon shoki 日本書紀 "Chronicles of Japan" or Nihongi 日本紀 has several references to tide jewels. Chapter 2 ("The Age of the Gods", Part 2) includes five versions of the Hoori-Hoderi myth, three of which mention the tide jewels. Chapter 8 ("Emperor Chūai") has a legend that Empress Jingū found a Buddhist nyoi-ju 如意珠 lit. "as-one-wishes jewel", and Chapter 9 ("Empress Jingū") tells how the Sea God and Wind God helped her to conquer the Korean kingdom of Silla.
Three of the five "Lost Fishhook" myth versions specifically mention Hoori using the tide jewels to control the tides and cause his fisherman brother Hoderi to submit. The other two variations involve controlling winds rather than tides. In the second version, the Sea God promises to directly control the sea winds; "if thy brother cross the sea, I will then assuredly stir up the blasts and billows, and make them overwhelm and vex him." In the fifth version, the water deity tells Hoori that whistling can create winds (cf. tides from Tangaroa's breathing); "Now that which raises the wind is whistling. If thou doest so, I will forthwith stir up the wind of the offing and the wind of the shore, and will overwhelm and vex him with the scurrying waves."
The first Nihongi version is consistent with the Kojiki, except that Hoori learns that Toyotama-hime is pregnant before, instead of after, returning home to Japan. It uses manju and kanju once each. The Sea God said. "If the Heavenly Grandchild desires to return to his country I will send him back." So he gave him the fish-hook which he had found, and in doing so instructed him, saying: "When thou givest this fish-hook to thy elder brother, before giving to him call to it secretly, and say, "A poor hook." He further presented to him the jewel of the flowing tide and the jewel of the ebbing tide, and instructed him, saying: "If thou dost dip the tide-flowing jewel, the tide will suddenly flow, and therewithal thou shalt drown thine elder brother. But in case thy elder brother should repent and beg forgiveness, if, on the contrary, thou dip the tide-ebbing jewel, the tide will spontaneously ebb, and therewithal thou shalt save him. If thou harass him in this way, thy elder brother will of his own accord render submission." … When Hiko-hoho-demi no Mikoto returned to his palace, he complied implicitly with the instructions of the Sea-God, and the elder brother, Ho-no-susori no Mikoto, finding himself in the utmost straits, of his own accord admitted his offence, and said: "Henceforward I will be thy subject to perform mimic dances for thee. I beseech thee mercifully to spare my life." Thereupon he at length yielded his petition, and spared him.
The third version of the myth mentions the tide jewels 9 times, and elaborates the feature of mind control. I am rejoiced in my inmost heart that the Heavenly Grandchild has now been graciously pleased to visit me. When shall I ever forget it? So he took the jewel which when thought of makes the tide to flow, and the jewel which when thought of makes the tide to ebb, and joining them to the fish-hook, presented them, saying: 'Though the Heavenly Grandchild may be divided from me by eightfold windings (of road), I hope that we shall think of each other from time to time. Do not therefore throw them away.' And he taught him, saying: 'When thou givest this fish-hook to thy elder brother, call it thus: 'A hook of poverty, a hook of ruin, a hook of downfall.' When thou hast said all this, fling it away to him with thy back turned, and deliver it not to him face to face. If thy elder brother is angry, and has a mind to do thee hurt, then produce the tide-flowing jewel and drown him therewith. As soon as he is in peril and appeals for mercy, bring forth the tide-ebbing jewel and therewith save him. If thou dost vex him in this way, he will of his own accord become thy submissive vassal!' Now Hiko-hoho-demi no Mikoto, having received the jewels and the fish-hook, came back to his original palace, and followed implicitly the teaching of the Sea-God. First of all he offered his elder brother the fish-hook. His elder brother was angry and would not receive it. Accordingly the younger brother produced the tide-flowing jewel, upon which the tide rose with a mighty overflow, and the elder brother was drowning. Therefore he besought his younger brother, saying: 'I will serve thee as thy slave. I beseech thee, spare my life.' The younger brother then produced the tide-ebbing jewel, whereupon the tide ebbed of its own accord, and the elder brother was restored to tranquility. After this the elder brother changed his former words, and said: 'I am thy elder brother. How can an elder brother serve a younger brother?' Then the younger brother produced the tide-flowing jewel, which his elder brother seeing, fled up to a high mountain. Thereupon the tide also submerged the mountain. The elder brother climbed a lofty tree, and thereupon the tide also submerged the tree. The elder brother was now at an extremity, and had nowhere to flee to. So he acknowledged his offence, saying: 'I have been in fault. In future my descendants for eighty generations shall serve thee as thy mimes in ordinary. [One version has' dog-men.'] I pray thee, have pity on me.' Then the younger brother produced the tide-ebbing jewel, whereupon the tide ceased of its own accord. Hereupon the elder brother saw that the younger brother was possessed of marvelous powers, and at length submitted to serve him.
The condensed fourth version mentions each tide jewel twice. 'When thou givest this to thy elder brother thou must recite the following : "A big hook, an eager hook, a poor hook, a silly hook." After saying all this, fling it to him with a back-handed motion.' Then he summoned together the sea-monsters, and inquired of them, saying: 'The Grandchild of the Heavenly Deity is now about to take his departure homewards. In how many days will you accomplish this service? 'Then all the sea-monsters fixed each a number of days according to his own length. Those of them which were one fathom long of their own accord said: 'In the space of one day we will accomplish it.' The one-fathom sea-monsters were accordingly sent with him as his escort. Then he gave him two precious objects, the tide-flowing jewel and the tide-ebbing jewel, and taught him how to use them. He further instructed him, saying: 'If thy elder brother should make high fields, do thou make puddle fields; if thy elder brother make puddle fields, do thou make high fields. In this manner did the Sea-God in all sincerity lend him his aid. Now Hiko-hoho-demi no Mikoto, when he returned borne, followed implicitly the God's instructions, and acted accordingly. When the younger brother produced the tide-flowing jewel, the elder brother forthwith flung up his hands in the agony of drowning. But when, on the other hand, he produced the tide-ebbing jewel, he was relieved, and recovered. After that Hi no susori no Mikoto pined away from day to day, and lamented, saying: 'I have become impoverished.' So he yielded submission to his younger brother.
The Nihongi chapters on legendary Emperor Chūai (supposedly r. 192–200 CE) and his shamanistic Empress Jingū (r. 201–269 CE) combine myths about Japanese kanju and manju tide jewels with Indian nyoi-ju 如意珠 "cintamani; wish-fulfilling jewels".