Book v Chapter 3

As for hair, men differ in this themselves at different ages, and also from all other kinds of animals that have hair. These are almost all which are internally viviparous, for even when the covering of such animals is spiny¹ it must be considered as a kind of hair, as in the land hedgehog and any other such animal among the vivipara. Hairs differ in respect of hardness and softness, length and shortness, straightness and curliness, quantity and scantiness², and in addition to these qualities, in their colours, whiteness and blackness and the intermediate shades. They differ also in some of these respects according to age, as they are young or growing old. This is especially plain in man; the hair gets coarser as time goes on, and some go bald on the front of the head; children indeed do not go bald, nor do women, but men do so by the time their age is advancing. Human beings also go grey on the head as they grow old, but this is not visible in practically any other animal, though more so in the horse than others. Men go bald on the front of the head, but turn grey first on the temples; no one goes bald first on these or on the back of the head. Some such affections occur in a corresponding manner also in all animals which have not hair but something analogous³ to it, as the feathers of birds and scales in the class of fish.

For what purpose Nature has made hair in general for animals has been previously⁴ stated in the work dealing⁵ with the causes of the parts of animals; it is the business of the present inquiry⁶ to show under what circumstances and for what necessary causes each particular kind of hair occurs. The principal cause then of thickness and thinness is the skin, for this is thick in some animals and thin in others, rare in some and dense⁷ in others. The different quality of the included moisture is also a helping⁸ cause, for in some animals this is greasy⁹ and in others watery¹⁰. For generally speaking the substratum of the skin is of an earthy nature; being on the surface of the body it becomes solid and earthy as the moisture evaporates. Now the hairs or their analogue¹¹ are not formed out of the flesh but out of the skin moisture evaporating and exhaling¹² in them, and therefore thick hairs arise from a thick skin and thin from thin. If then the skin is rarer and thicker, the hairs are thick because of the quantity of earthy matter and the size of the pores, but if it is denser¹³ they are thin because of the narrowness of the pores. Further, if the moisture be watery it dries up quickly and the hairs do not gain in size, but if it be greasy the opposite happens, for the greasy is not easily dried up. Therefore the thicker-skinned animals are as a general rule thicker-haired for the causes mentioned; however, the thickest-skinned are not more so than other thick-skinned ones, as is shown by the class of swine compared to that of oxen and to the elephant and many others. And for the same reason also the hairs of the head in man are thickest, for this part of his skin is thickest and lies over most moisture and besides is very porous¹⁴.

The cause of the hairs being long or short depends on the evaporating moisture not being easily dried. Of this there are two causes, quantity and quality; if the liquid is much it does not dry up easily nor if it is greasy. And for this reason the hairs of the head are longest in man, for the brain, being fluid and cold, supplies great abundance of moisture.

The hairs become straight or curly on account of the vapour arising in them. If it be smoke-like, it is hot and dry and so makes the hair curly, for it is twisted as being carried with a double motion, the earthy part tending downwards¹⁵ and the hot upwards¹⁶. Thus, being easily bent¹⁷, it is twisted owing to its weakness, and this is what is meant by curliness in hair. It is possible then that this is the cause, but it is also possible that, owing to its having but little moisture and much earthy matter in it, it is dried by the surrounding air and so coiled up together. For what is straight becomes bent, if the moisture in it is evaporated, and runs together as a hair does when burning upon the fire; curliness will then be a contraction¹⁸ owing to deficiency of moisture caused by the heat of the environment. A sign of this is the fact that curly hair is harder than straight, for the dry is hard. And animals with much moisture are straight-haired; for in these hairs the moisture advances as a stream, not in drops. For this reason the Scythians on the Black Sea and the Thracians are straight-haired, for both they themselves and the environing air are moist, whereas the Aethiopians and men in hot countries are curly-haired, for their brains and the surrounding air are dry.

Some, however, of the thick-skinned animals are fine-haired for the cause previously stated, for the finer the pores are the finer must the hairs be. Hence the class of sheep have such hairs (for wool is only a multitude of hairs).

There are some animals whose hair is soft and yet less fine, as is the case with the class of hares compared with that of sheep; in such animals the hair is on the surface of the skin, not deeply rooted in it, and so is not long but in much the same state as the scrapings from linen¹⁹, for these also are not long but are soft and do not admit of weaving.

The condition of sheep in cold climates is opposite to that of man; the hair of the Scythians is soft but that of the Sauromatic sheep is hard. The reason of this is the same as it is also all wild animals. The cold hardens and solidifies²⁰ them by drying them, for as the heat is pressed out the moisture evaporates, and both hair and skin become earthy and hard. In wild animals then the exposure to the cold is the cause of hardness in the hair, in the others the nature of the climate is the cause. A proof of this is also what happens in the sea-urchins which are used as a remedy in stranguries. For these, too, though small themselves, have large and hard spines²¹ because the sea in which they live is cold on account of its depth (for they are found in sixty fathoms²² and even more). The spines are large because the growth of the body is diverted to them, since having little heat in them they do not concoct²³ their nutriment and so have much residual²⁴ matter and it is from this that spines, hairs, and such things are formed; they are hard and petrified²⁵ through the congealing²⁶ effect of the cold. In the same way also plants are found to be harder, more earthy, and stony²⁷, if the region in which they grow looks to the north than if it looks to the south, and those in windy places than those in sheltered, for they are all more chilled and their moisture evaporates.

Hardening, then, comes of both heat and cold, for both cause the moisture to evaporate, heat per se and cold per accidens (since the moisture goes out of things along with the heat, there being no moisture without heat), but whereas cold not only hardens but also condenses, heat makes a substance rarer.

For the same reason, as animals grow older, the hairs become harder in those which have hairs, and the feathers and scales in the feathered and scaly²⁸ kinds. For their skins become harder and thicker as they get older, for they are dried up, and old age, as the word denotes, is earthy because the heat fails and the moisture along with it.

Men go bald visibly more than any other animal, but still such a state is something general, for among plants also some are evergreens²⁹ while others are deciduous³¹, and birds which hibernate³² shed their feathers. Similar to this is the condition of baldness in those human beings to whom it is incident. For leaves are shed by all plants, from one part of the plant at a time, and so are feathers and hairs by those animals that have them; it is when they are all shed together that the condition is described by the terms mentioned, for it is called ‘going bald’ and ‘the fall of the leaf’ and ‘moulting’. The cause of the condition is deficiency of hot moisture, such moisture being especially the unctuous³³, and hence unctuous plants are more evergreen³⁰. (However we must elsewhere state the cause of this phenomena³⁴ in plants, for other causes also contribute to it.) It is in winter that this happens to plants (for the change from summer to winter is more important to them than the time of life), and to those animals which hibernate (for these, too, are by nature less hot and moist than man); in the latter it is the seasons of life that correspond to summer and winter. Hence no one goes bald before the time of sexual intercourse³⁵, and at that time it is in those naturally inclined to such intercourse that baldness appears, for the brain is naturally the coldest part of the body and sexual intercourse makes men cold, being a loss of pure natural heat. Thus we should expect the brain to feel the effect of it first, for a little cause turns the scale where the thing concerned is weak and in poor condition. Thus if we reckon up these points, that the brain itself has but little heat, and further that the skin round it must needs have still less, and again that the hair must have still less than the skin inasmuch as it is furthest removed from the brain, we should reasonably expect baldness to come about this age upon those who have much semen. And it is for the same reason that the front part of the head alone goes bald in man and that he is the only animal to do so; the front part goes bald because the brain is there, and man is the only animal to go bald because his brain is much the largest and the moistest. Women do not go bald because their nature is like that of children, both alike being incapable³⁶ of producing seminal³⁷ secretion³⁸. Eunuchs do not become bald, because they change into the female condition. And as to the hair that comes later in life, eunuchs either do not grow it at all, or lose it if they happen to have it, with the exception of the pubic hair; for women also grow that though they have not the other, and this mutilation is a change from the male to the female condition.

The reason why the hair does not grow again in cases of baldness, although both hibernating³⁹ animals recover their feathers or hair and trees that have shed their leaves grow leaves again, is this. The seasons of the year are the turning-points of their lives, rather than their age, so that when these seasons change they change with them by growing and losing feathers, hairs, or leaves respectively. But the winter and summer, spring and autumn of man are defined by his age, so that, since his ages do not return, neither do the conditions caused by them return, although the cause of the change of condition is similar in man to what it is in the animals and plants in question.

We have now spoken pretty much of all the other conditions of hair.

1 spiny   

adj.多刺的，刺状的；n.多刺的东西

参考例句：

• This is the Asiatic ornamental shrub with spiny branches and pink blossoms.这就是亚洲的一种观赏灌木，具有多刺的枝和粉红色的花。
• Stay away from a spiny cactus.远离多刺仙人掌。

2 scantiness   

n.缺乏

参考例句：

3 analogous   

adj.相似的；类似的

参考例句：

• The two situations are roughly analogous.两种情況大致相似。
• The company is in a position closely analogous to that of its main rival.该公司与主要竞争对手的处境极为相似。

4 previously   

adv.以前，先前（地）

参考例句：

• The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
• Let me digress for a moment and explain what had happened previously.让我岔开一会儿，解释原先发生了什么。

5 dealing   

n.经商方法，待人态度

参考例句：

• This store has an excellent reputation for fair dealing.该商店因买卖公道而享有极高的声誉。
• His fair dealing earned our confidence.他的诚实的行为获得我们的信任。

6 inquiry   

n.打听，询问，调查，查问

参考例句：

• Many parents have been pressing for an inquiry into the problem.许多家长迫切要求调查这个问题。
• The field of inquiry has narrowed down to five persons.调查的范围已经缩小到只剩5个人了。

7 dense   

a.密集的，稠密的，浓密的；密度大的

参考例句：

• The general ambushed his troops in the dense woods. 将军把部队埋伏在浓密的树林里。
• The path was completely covered by the dense foliage. 小路被树叶厚厚地盖了一层。

8 helping   

n.食物的一份&adj.帮助人的，辅助的

参考例句：

• The poor children regularly pony up for a second helping of my hamburger. 那些可怜的孩子们总是要求我把我的汉堡包再给他们一份。
• By doing this, they may at times be helping to restore competition. 这样一来, 他在某些时候,有助于竞争的加强。

9 greasy   

adj. 多脂的，油脂的

参考例句：

• He bought a heavy-duty cleanser to clean his greasy oven.昨天他买了强力清洁剂来清洗油污的炉子。
• You loathe the smell of greasy food when you are seasick.当你晕船时，你会厌恶油腻的气味。

10 watery   

adj.有水的，水汪汪的；湿的，湿润的

参考例句：

• In his watery eyes there is an expression of distrust.他那含泪的眼睛流露出惊惶失措的神情。
• Her eyes became watery because of the smoke.因为烟熏，她的双眼变得泪汪汪的。

11 analogue   

n.类似物；同源语

参考例句：

• The gill of a fish is the analogue of the lung of a cat.鱼的鳃和猫的肺是类似物。
• But aside from that analogue standby,the phone, videoconferencing is their favorite means of communication.除了备用的相似物电话，可视对话是他们最喜欢的沟通手段。

12 exhaling   

v.呼出，发散出( exhale的现在分词 )；吐出（肺中的空气、烟等），呼气

参考例句：

• Take a deep breath inhaling slowly and exhaling slowly. 深呼吸，慢慢吸进，慢慢呼出。 来自互联网
• Unclasp your hands and return to the original position while exhaling. 呼气并松开双手恢复到原位。 来自互联网

13 denser   

adj. 不易看透的, 密集的, 浓厚的, 愚钝的

参考例句：

• The denser population necessitates closer consolidation both for internal and external action. 住得日益稠密的居民，对内和对外都不得不更紧密地团结起来。 来自英汉非文学 - 家庭、私有制和国家的起源
• As Tito entered the neighbourhood of San Martino, he found the throng rather denser. 蒂托走近圣马丁教堂附近一带时，发现人群相当密集。

14 porous   

adj.可渗透的，多孔的

参考例句：

• He added sand to the soil to make it more porous.他往土里掺沙子以提高渗水性能。
• The shell has to be slightly porous to enable oxygen to pass in.外壳不得不有些细小的孔以便能使氧气通过。

15 downwards   

adj./adv.向下的（地），下行的（地）

参考例句：

• He lay face downwards on his bed.他脸向下伏在床上。
• As the river flows downwards,it widens.这条河愈到下游愈宽。

16 upwards   

adv.向上，在更高处...以上

参考例句：

• The trend of prices is still upwards.物价的趋向是仍在上涨。
• The smoke rose straight upwards.烟一直向上升。

17 bent   

n.爱好，癖好；adj.弯的；决心的，一心的

参考例句：

• He was fully bent upon the project.他一心扑在这项计划上。
• We bent over backward to help them.我们尽了最大努力帮助他们。

18 contraction   

n.缩略词，缩写式，害病

参考例句：

• The contraction of this muscle raises the lower arm.肌肉的收缩使前臂抬起。
• The forces of expansion are balanced by forces of contraction.扩张力和收缩力相互平衡。

19 linen   

n.亚麻布，亚麻线，亚麻制品；adj.亚麻布制的，亚麻的

参考例句：

• The worker is starching the linen.这名工人正在给亚麻布上浆。
• Fine linen and cotton fabrics were known as well as wool.精细的亚麻织品和棉织品像羊毛一样闻名遐迩。

20 solidifies   

（使）成为固体，（使）变硬，（使）变得坚固( solidify的第三人称单数 )； 使团结一致； 充实，巩固； 具体化

参考例句：

• Jelly solidifies as it gets cold. 肉冻冷却就凝固。
• It is stirred with 10%sodium carbonate solution(50ml)and then with water (50ml), after which It'solidifies. 与10％碳酸钠溶液（50毫升）混合搅拌，然后再用50毫升水混合搅拌，从而析出固体。

21 spines   

n.脊柱( spine的名词复数 )；脊椎；（动植物的）刺；书脊

参考例句：

• Porcupines use their spines to protect themselves. 豪猪用身上的刺毛来自卫。
• The cactus has spines. 仙人掌有刺。 来自《现代英汉综合大词典》

22 fathoms   

英寻( fathom的名词复数 )

参考例句：

• The harbour is four fathoms deep. 港深为四英寻。
• One bait was down forty fathoms. 有个鱼饵下沉到四十英寻的深处。

23 concoct   

v.调合，制造

参考例句：

• I gave her a tip on how to concoct a new kind of soup.我教她配制一种新汤的诀窍。
• I began to concoct explanations of my own.我开始思考自己的解释。

24 residual   

adj.复播复映追加时间；存留下来的，剩余的

参考例句：

• There are still a few residual problems with the computer program.电脑程序还有一些残留问题。
• The resulting residual chromatism is known as secondary spectrum.所得到的剩余色差叫做二次光谱。

25 petrified   

adj.惊呆的；目瞪口呆的v.使吓呆，使惊呆；变僵硬；使石化(petrify的过去式和过去分词)

参考例句：

• I'm petrified of snakes. 我特别怕蛇。
• The poor child was petrified with fear. 这可怜的孩子被吓呆了。 来自《简明英汉词典》

26 congealing   

v.使凝结，冻结( congeal的现在分词 )；（指血）凝结

参考例句：

• Vague European uneasiness was congealing into panic. 欧洲各国先是隐约不安，后来逐渐惊慌失措起来。 来自辞典例句
• The process of congealing or the state of being congealed. 凝结的过程或被凝结后的状态。 来自互联网

27 stony   

adj.石头的，多石头的，冷酷的，无情的

参考例句：

• The ground is too dry and stony.这块地太干，而且布满了石头。
• He listened to her story with a stony expression.他带着冷漠的表情听她讲经历。

28 scaly   

adj.鱼鳞状的；干燥粗糙的

参考例句：

• Reptiles possess a scaly,dry skin.爬行类具有覆盖着鳞片的干燥皮肤。
• The iron pipe is scaly with rust.铁管子因为生锈一片片剥落了。

29 evergreens   

n.常青树，常绿植物，万年青( evergreen的名词复数 )

参考例句：

• The leaves of evergreens are often shaped like needles. 常绿植物的叶常是针形的。 来自《简明英汉词典》
• The pine, cedar and spruce are evergreens. 松树、雪松、云杉都是常绿的树。 来自辞典例句

30 evergreen   

n.常青树；adj.四季常青的

参考例句：

• Some trees are evergreen;they are called evergreen.有的树是常青的，被叫做常青树。
• There is a small evergreen shrub on the hillside.山腰上有一小块常绿灌木丛。

31 deciduous   

adj.非永久的；短暂的；脱落的；落叶的

参考例句：

• Overgrown deciduous shrubs can be cut back at this time of year.过于繁茂的落叶灌木可以在每年的这个时候修剪。
• Deciduous trees shed their leaves in autumn.落叶树木在秋天落叶。

32 hibernate   

v.冬眠，蛰伏

参考例句：

• Bears often hibernate in caves.熊常在山洞里冬眠。
• Some warm-blooded animals do not need to hibernate.一些温血动物不需要冬眠。

33 unctuous   

adj.油腔滑调的，大胆的

参考例句：

• He speaks in unctuous tones.他说话油腔滑调。
• He made an unctuous assurance.他做了个虚请假意的承诺。

34 phenomena   

n.现象

参考例句：

• Ade couldn't relate the phenomena with any theory he knew.艾德无法用他所知道的任何理论来解释这种现象。
• The object of these experiments was to find the connection,if any,between the two phenomena.这些实验的目的就是探索这两种现象之间的联系，如果存在着任何联系的话。

35 intercourse   

n.性交；交流，交往，交际

参考例句：

• The magazine becomes a cultural medium of intercourse between the two peoples.该杂志成为两民族间文化交流的媒介。
• There was close intercourse between them.他们过往很密。

36 incapable   

adj.无能力的，不能做某事的

参考例句：

• He would be incapable of committing such a cruel deed.他不会做出这么残忍的事。
• Computers are incapable of creative thought.计算机不会创造性地思维。

37 seminal   

adj.影响深远的；种子的

参考例句：

• The reforms have been a seminal event in the history of the NHS.这些改革已成为英国国民保健制度史上影响深远的一件大事。
• The emperor's importance as a seminal figure of history won't be diminished.做为一个开创性历史人物的重要性是不会减弱的。

38 secretion   

n.分泌

参考例句：

• Is there much secretion from your eyes?你眼里的分泌物多吗？
• In addition,excessive secretion of oil,water scarcity are also major factors.除此之外，油脂分泌过盛、缺水也都是主要因素。

39 hibernating   

（某些动物）冬眠，蛰伏( hibernate的现在分词 )

参考例句：

• The hibernating animals reduce movement to far below the ordinary level. 冬眠的动物把活动量大大减少到低于一般的水平。
• People find hibernating animals asleep. 人们发现冬眠动物处于休眠状态。