for one thing-譬如，举个例子的意思。全句我的理解为：

There was so much to read, for one thing, and so much fine health to be pulled down out of the young breath-giving air.  有太多东西要看了，譬如，就那些新鲜东西（证券之类的书籍，下一句提到）就让我够呛。