I was hurt. Still more of that wretched fish! But now I set myself to my task with a will, and discovered one new thing after another, until I saw how just the Professor's criticism had been. The afternoon passed quickly; and when, towards its close, the Professor inquired, "Do you see it yet?"
This was disconcerting. Not only must I think of my fish all night, studying, without the object before me, what this unknown but most visible feature might be, but also, without reviewing my discoveries, I must give an exact account of them the next day.
1、when此句中是副词，还是连词？
2、studying分词短语在句中干什么状语？
【1】when为从属连词，引导时间状语从句
【2】studying为目前分词作前面分句谓语动词think of的随着状语，without the object before me为目前分词studying方法状语， what this unknown but most visible feature might be,为目前分词studying宾语从句。
备注:句子整体框架结构：Not only +倒装结构，studying, without....what...... but also without..., +陈述句子
Not only 【must I think of my fish all night】, studying, 【without the object before me】, 【what this unknown but most visible feature might be, 】but also, 【without reviewing my discoveries】, 【I must give an exact account of them the next day】.
备注:Not only提前句首，接句子需要使用倒装结构 Not only+ //+主语+谓语动词+其它，but also+主语+谓语动词+其它 =不只主语A要做某事，而且主语A还要做某事。
