broken reed

Isabella Birdの "Unbeaten Tracks in Japan" を読んでいます。
列車や車はない時代に、英国の女性が日本の田舎、東北や北海道を旅をするなんて凄いことです。ともかく旅が始まりました。

From the date you will see that I have started on my long journey, though not upon the "unbeaten tracks”which I hope to take after leaving Nikko, and my first evening alone in the midst of this crowded Asian life is strange, almost fearful. I have suffered from nervousness all day--the fear of being frightened, of being rudely mobbed, as threatened by Mr. Campbell of Islay, of giving offence by transgressing the rules of Japanese politeness--of, I know not what! Ito is my sole reliance, he may prove a “broken reed.” I often wished to give up my project, but was ashamed of my cowardice when, on the best authority, I received assurances of its safety.

やはり不安はあったようですね。さて、"broken reed" の意味を調べます。
・Collins Dictionary: a weak, unreliable, or ineffectual person:

・Wiktionary: Something or someone very fragile or unreliable.: Many of the big estates survived. Nor was the peasantry a broken reed in terms of demand for manufactured products.
・McGraw-Hill Dictionary of American Idioms and Phrasal Verbs: an unreliable or undependable person. (On the image of a useless, broken reed in a reed instrument.) You can't rely on Jim's support. He's a broken reed.

確かに通訳として雇った Ito 青年だけが頼りの状況ですが、まだ不安なだけ。