But my blood surged with excitedment, as if I had already flown out of the room,straddled the neck of the North Wind and galloped off into space.

分析这个词组的结构，看意思：

galloped （不及物动词：飞奔）off （副词小品词：脱离房间甚至地球）into （介词：进入）space（太空）

网友把上面分析的词义联系起来，就知道具体是什么意思了。