“Lieutenant Davis, U.S. Navy, suggests, ‘Hitherto we have used the English Meridian of Greenwich; all our astronomical calculations are fixed according to that, our nautical charts are adapted to it, and our chronometers are set to its time. The scientific importance of assuming an American Meridian is undoubted.’ So long as we depend upon that from which we are separated by an ocean, our absolute longitudes remain indeterminate. There is no place on our coast, the longitude of which from Greenwich is so well ascertained as Boston. Yet there still exists an uncertainty in this longitude, of perhaps two seconds of time.”
“美国海军戴维斯中尉建议，‘到目前为止，我们使用的是格林威治的英国子午线；我们所有的天文计算都是根据这一点确定的，我们的海图是根据它调整的，我们的计时器是按照它的时间设置的。假设美国子午线的科学重要性是毋庸置疑的。只要我们依赖被海洋隔开的东西，我们的绝对经度仍然是不确定的。在我们的海岸上没有一个地方，从格林威治来的经度比波士顿更清楚。然而，在这个经度上仍然存在着一种不确定性，可能只有两秒钟的时间。“
—Scientific American, September 1849
-“科学美国人”，1849年9月
More gems from Scientific American’s first 175 years can be found on our shiny anniversary page.
更多来自科学美国人头175年的宝石可以在我们闪亮的周年纪念页面上找到。
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