[Day 702 2016-08-28]Lesson 42-4 Recording an earthquake
課文
But as the paper moved from side to side under the pen point, its movement would be recorded in ink upon its surface. It was upon this principle that the first instruments were made, but the paper was wrapped round a drum which rotated slowly. As long as all was still, the pen drew a straight line, but while the drum was being shaken, the line that the pen was drawing wriggled from side to side. The apparatus thus described, however, records only the horizontal component of the wave movement, which is, in fact, much more complicated. If we could actually see the path described by a particle, such as a sand grain in the rock, it would be more like that of a bluebottle buzzing round the room;
生詞：
1.drum(n.)鼓
2.wrap(v.)包裝
ex.He wrapped her bitrhday gift.
3.wriggle(v.)
ex.She is wriggling on his bed all the time
4.grain(n.)沙粒、穀物
ex.has not a grain of courage
問題回答
課文涉及哪些訊息？
記錄地震軌跡的方式
表達啥意思？
像是：
在水瓶紀錄地震軌跡與垂直軌跡的敘述
我可以應用在啥場景？
描述自己地震垂直面的震動
record the horizontal component of wave movement
哪些詞讓我印象深刻？
we could see the path describled by a particle.
我可以積累啥半成品？
a grain of courage
