Sentence:  Passing by those clauses of it which demand no notice, we arrive at that which provides that "each proposal (for purchase) must state the price per picul of rice in gold <WSD>"yen</WSD>"." But why in gold <WSD>"yen</WSD>", a coin as yet so scarce as to be almost beyond the ken of the foreign merchant? 
Meaning of the word marked with <WSD> tags:  The unit of Japanese currency (symbol: ¥) since 1871, divided into 100 sen.