classic waka stream

尋ねても跡はかくても水茎の
行方も知らぬ昔なりけり
Roma-ji

Tazunete mo ato wa kakute mo mizuguki no yukue mo shiranu mukashi narikeri

English Translation
Though I seek it out,
though the traces stay written thus,
like the brush's stream
its course is lost to me—
such is the past, I find.
Meaning
Though I seek it out, and though the brush traces remain written here like this, the past, like water flowing from the brush, has gone where no one knows.
Commentary
Book Eight Lament Poems 806

Headnote: "On seeing, at the residence of the Consort of the Ise Priestess, a booklet written by the late emperor."
This is the second poem of the sequence remembering the dead through their handwriting, and the opening poem of an exchange. It says that though she seeks it, and though the brush traces remain written thus, the past has gone where no one knows. According to the headnote, it was composed on seeing a booklet written by the late emperor at the residence of the Consort of the Ise Priestess.
The author was a lady-in-waiting and poet of the mid-Heian period who served Princess Kishi, the Consort of the Ise Priestess, among others. She is one of the Thirty-Six Later Poetic Immortals. The "Consort of the Ise Priestess" is Princess Kishi, a consort of Emperor Murakami. The "late emperor" is Emperor Murakami.
The scene is the time after Emperor Murakami's death, set at the residence of the Consort of the Ise Priestess.
The direct occasion is seeing a booklet written in Emperor Murakami's hand at the residence of the Consort of the Ise Priestess.

The first line, "tazunete mo," means "though I seek it out." It shows a heart searching for the past that is gone.
In the second line, "ato wa kakute mo," "ato" is the brush trace. "Kaku" is a pivot word meaning both "kaku," thus, and "kaku," to write, so that it means "though the brush traces remain written thus."
In the third line, "mizuguki no," "mizuguki" means the brush or handwriting. Through its "mizu," water, it leads into "yukue," course, in the fourth line.
The fourth line, "yukue mo shiranu," means "whose course is unknown, like water that has flowed away." "Yukue" is a word associated with the "water" of "mizuguki."
In the last line, "mukashi narikeri," "keri" is exclamatory, showing the realization that such is the past. Though the handwriting remains before her eyes, the one who wrote it and the days gone by cannot be traced. Following the handwriting on the fan in the preceding poem, 805, this poem sings of an emperor's handwriting. The next poem, 807, replies by taking up this "mizuguki."
Author
Uma no Naishi
Source
Shin Kokin Wakashu
Other