Ame furaba kimu to omoeru Kasa no yama hito ni na kise so nure wa hitsu tomo

雨降らば着むと思へる笠の山
人にな着せそ濡れは漬つとも

Roma-ji: Ame furaba kimu to omoeru Kasa no yama hito ni na kise so nure wa hitsu tomo
English Translation: If the rain should fall,
I think to wear it on my head—
that Mount Kasa, the "Hat":
don't let others put it on,
though I be soaked through and through.
Meaning: Mount Kasa, which I mean to wear like a hat if it rains—do not let anyone else wear it, even if I am drenched to the bone.
Commentary: Book Three Miscellaneous Poems 374

Headnote: "A poem by Isonokami no Otomaro no Ason"
Likening Mount Kasa ("Hat Mountain") to his own hat, which he means to wear if it rains, the poet calls out that no one else be allowed to wear it. It is read as an allegory, the hat standing for the woman he loves: he wishes she not be given to another man. Mount Kasa is identified with Mount Mikasa in Nara or with a mountain at Kasa in Sakurai.
The poet, Isonokami no Otomaro, was a son of Isonokami no Maro. He was exiled to Tosa in Tenpyō 11 (739) but later pardoned, and rose to Middle Counselor.

First line "If the rain should fall" states the condition.
Second line "I think to wear it on my head": kiru here means to put on a hat.
Third line "that Mount Kasa, the 'Hat'" overlays the mountain with his own hat.
Fourth line "don't let others put it on": na ... so is a prohibition; the sentence breaks here.
Fifth line "though I be soaked through and through": hitsu means to be drenched, ending with the force of his feeling.
Author: Isonokami no Otomaro
Source: Manyoshu
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