陈列像磨石头、巨树和陨石之类的东西，基本上是靠机械操作的。多数其他自然史展品则带来更多的难题。比如，一个小得看不清的生物如何展出呢？面临这些情况，便要制作大于实物的模型。美国自然史博物馆里陈列着放大到74倍的蚤、家蝇和万千种其他昆虫。这些模型展示了各种昆虫的各个发育阶段和它们的身体功能。
The Antarctic，a Desert of Ice All Year Round
The antarctic is actually a desert．It is the only continent on the earth without a river or a lake．
The antarctic is all ice all year round．The warmest temperature ever recorded there is zero，at the South Pole．Explorers used to think that a place so cold would have a heavy snowfall．But less than ten inches of snow falls each year．That is less than half an inch of water．Ten times that much moisture falls in parts of the Sahara．
The little snow that falls in Antarctica never melts．It continues to pile up deeper and deeper year after year and century after century．When the snow gets to be about eighty feet deep it is turned to ice by the weight of the snow above it．
南极——终年冰封的不毛之地
南极地区实际上是一片不毛之地，它是地球上唯一没有河流也没有湖泊的大陆。
南极地区终年冰封。那儿历史上的最高气温纪录是零度，那还是在南极点。探险家们过去总认为，如此寒冷的地方可能会有纷飞的大雪，但是，那儿每年的降雪却不足10英寸厚，还没有半英寸水多。撒哈拉沙漠一些地区的降雨量还是那儿的10倍呢！
降于南极洲的微量的雪从不融化，年复一年，一个世纪又一个世纪地越积越厚。当积雪达80英尺的时候，受上层重压的雪就会凝结成冰。
The Badger，a Courageous Fighter
The badger has been nicknamed“doormat”because of its broad，squat form and its hairy back．Actually it is a courageous fighter．In pioneer days it was considered great sport to turn a pack of dogs loose on this furry foe，but few dogs were willing to challenge the badger a second time．
When attacked，the badger digs a protective hole；if cornered，it releases a strong odor from glands near its tail．The badger，s height-only about nine inches-places its throat below the line of attack of most dogs，and the back of its neck is protected by coarse hair．
In a fight，the badger，s front claws are for midable weapons．It can leave a dog limping after one wellplaced bite of its sharp teeth．Only the lowslung dachshund can easily get a deadly throat hold on the badger；this dog was once much used in“badgering”．Fortunately for the badger，the popularity of this sport has decreased considerably．
獾——勇猛的斗士
獾，因其宽宽的、矮墩墩的形体和毛茸茸的背部一直被人们浑称为“门垫”。实际上，它是一名勇猛的斗士。在拓荒者年代，放出一群狗与这个有毛皮的对手相斗被认为是极精彩的娱乐。然而，极少有狗愿意向獾作第二次挑战。
獾在受到进攻时，便刨一个洞藏身；在它走头无路时，就从靠近尾部的腺体释放出一种浓烈的气味。獾的高度——仅9英寸左右，使其喉管处于大多数狗的进攻线以下，它的颈背有粗糙的毛保护着。
在搏斗中，獾的前爪是锐不可挡的武器。獾瞄准了狗的腿部，用利齿咬上一口便可使它成为跛足。只有形体矮小的猎獾狗，能轻而易举地咬住它的喉管而致它于死地。这种狗曾广泛用于“狗撩獾”运动中。对獾说来，幸运的是，这项运动的风靡程度已大大下降了。
The Best Season for Thinking
If you are like most people，your intelligence varies from season to season．You are probably a lot sharper in the spring than you are at any other time of year．A noted scientist，Ellsworth Huntington（1876-1947），concluded from other men，s work and his own among peoples in different climates that climate and temperature have a definite effect on our mental abilities．
He found that cool weather is much more favorable for creative thinking than is summer heat．This does not mean that all people are less intelligent in the summer than they are during the rest of the year．It does mean，however，that the mental abilities of large numbers of people tend to be lowest in the summer．
Spring appears to be the best period of the year for thinking．One reason may be that in the spring man，s mental abilities are affected by the same factors that bring about great changes in all nature．
Fall is the nextbest season，then winter．As for summer，it seems to be a good time to take a long vacation from thinking！
思考的最佳季节
如果你和大多数人没有什么两样，那么，你的智力也是随着季节的更替而变化的。你在春天可能要比一年中的其他时间敏锐得多。着名科学家埃尔斯沃思·亨廷顿（1876-1947），根据自己和别人在不同气候条件下的工作情况，断定气候和气温对我们的智能确有影响。
他发现，凉爽的天气比酷暑远远有利于创造性的思考。这并不是说所有的人在夏天比一年中的其他时间都要愚钝些。然而，这确实意味着，相当多的人的智能在夏天趋向于最低点。
春天似乎是一年中最利于人们思考的一段时间，其原因可能是，春天给整个大自然带来巨大变化的因素，同样也给人类智能带来影响。
秋天是第二个最好的季节，其次是冬天，至于夏天，它似乎是一段人们不动脑筋、休长假的好时光。
