, to the north of the ke. these stones, when decomposed by heat, made a very strong quicklime, greatly increased by scking, at least as pure as if it had been produced by the calcination of chalk or marble. mixed with sand the lime made excellent mortar.
这期间,居民们首先制造出一只烹调用的陶土罐。主要原料是陶土,哈顿在里面加了一些石灰和石英混合起来就成了正式的“管土”。他们拿适当形状的石头作模子,用陶土做成饭碗、茶杯,另外又做了一些盛水的大壶等等。
in the meantime what the settlers first manufactured was a common pottery in which to cook their food. the chief material was cy, to which harding added a little lime and quartz. this paste made regur “pipe-cy,“ with which they manufactured bowls, cups molded on stones of a proper size, great jars and pots to hold water, etc.
初升的月亮照亮了南边的水平线,在天空的衬托下,这部分水平线显得十分清晰。这时候,南十字座出现在观察家的眼前了,十字架二倒置在星座的底部,也就是离南极较近的地方。这个星座离南极比北极星离北极远。十字架二大约在距南极27度的方位,赛勒斯?哈顿知道这一点,在计算的时候就把这个角度估计在内了。当十字架二经过正对着南极的子午线时,他也仔细地进行了观察,这样工作就简单了。
赛勒斯?哈顿把圆规的一只脚对着水平线,另一只脚对着十字架二,两只规脚之间的距离,就形成了十字架二和水平线之间的角距。为了把所得的这个角度固定下来,他用刺针把一根木条横钉在圆规的两只脚上,这样就可以把它们之间的角度适当地保留下来。
做完了这一步工作,下一步只要计算一下角度就行了。但是首先要把水平线的俯角考虑在内,因此必须再到海平面上去进行观察,量一下峭壁的高度。有了上述的角度就可以求出十字架二的高度,从这里也可以求出天极在水平线上的高度,也就是海岛的纬度,困为地球上任何一个地方的纬度都永远等于当地天极在水平线上的高度。
to the south the horizon, lighted by the first rays of the moon, was very clearly defined against the sky.
at this moment the southern cross presented itself to the observer in an inverted position, the star alpha marking its base, which is nearer to the southern pole.
this consteltion is not situated as near to the
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