It tires not, nor does it boast of its power; but belongs to the air,travelling it may be six thousand miles to and from its northern nesting home, feeding its flown young as it flies, and slipping through a medium that seems to help its passage even when the wind is adverse.
参考译文：燕子充分兼有这两类鸟的长处，它既不疲劳，也不炫耀我们的飞翔力；在空中十分自如，可以飞行6,000英里，可以飞往北方做窝的老家，再从老家飞回；一边飞一边喂养会飞的雏燕，甚至在顶风时也能在气流中滑翔，好像气流在帮它前进。（除此之外，«自学导读»里有这句子的分解：a medium 指 air，nesting home 意为 home for nesting）
问题1：此处的to是和后面的and from连在一块理解的吗，to its northern nesting home and from its northern nesting home是如此理解的吗？还是另有其他的理解方法？
问题2：nesting home 是鸟巢的意思吗？
问题3：medium 是媒介，办法的意思吗，如此理解可以吗？
网友的理解基本正确，我补充一点内容供网友参考。
It tires not, nor does it boast of its power; but belongs to the air,travelling it may be six thousand miles to and from its northern nesting home, feeding its flown young as it flies, and slipping through a medium that seems to help its passage even when the wind is adverse.
【1】It tires not, nor does it boast of its power为分句
【2】but belongs to the air,travelling it may be six thousand miles to and from its northern nesting home, feeding its flown young as it flies, and slipping through a medium that seems to help its passage even when the wind is adverse.为分句
备注：分句1和分句2构成转折关系的并列句
but belongs to the air,travelling it may be six thousand miles to and from its northern nesting home, feeding its flown young as it flies, and slipping through a medium that seems to help its passage even when the wind is adverse.
【1】travelling it may be six thousand miles to and from its northern nesting home,
备注：travelling it may be....nesting time为倒装结构，还原后为it may be travelling six thousand miles to and from, it为句子主语，may be travelling为句子谓语动词，six thousand miles为句子状语, to northern nesting home为句子状语，and为连词，from its northern nesting home为句子状语。
【2】feeding its flown young as it flies,
备注：以上为目前分词作状语，as it flies为as引导时间状语从句作目前分词短语的时间状语。
【3】and slipping through a medium that seems to help its passage even when the wind is adverse.
备注：以上为目前分词作状语，that seems to help its passage even when the wind is adverse.为关系代词that引导的定语从句修饰名词a medium，关系代词that在定语从句作主语，when the wind is adverse为定语从句时间状语，修饰定语从句谓语seem to help its passages.
总结：2和3为由连词and连接2个并列目前分词短语作状语。修饰前面句子谓语:may be travelling six thousand miles to and from its northern nesting home。