It would look odd to be entirly silent for half an hour together, and yet for the advantage of some,conversation ought to be so arranged as that they may have the trouble of saying as little as possible.

so arranged as that中，as疑为印刷错误，as应去掉。so...that...结构中，that引导结果状语从句。

Mr.Wickham is blessed with such happy manners as may ensure his making friends.

such+名词+as从句，传统语法认为as为关系代词，指代被such修饰的名词happy manners。但这种解释有逻辑错误。因为as表示比较意义，既然是比较，必然涉及不同的人和事物，所以as不可能与happy manners 共指同一个事物，as只是替代了名词，然后作比较，二者相同。所以现代语法认为as引导的是比较分句，将such happy manners 和as替代的主语相比较。现代语法的分词符合逻辑，是正确的分析。不过如果网友没有学习过现代语法，那么按照传统语法将as理解为关系代词引导定语从句也是可以的。但要注意as并不是指代全句内容，而是指代such修饰的名词。