CHAPTER III. MARINE BRICK-EARTHS.

 Turning to brick-earths of marine¹ origin, we may say that these constitute by far the largest class of deposits from which bricks are made in this country, and it will be useful to deal with their origin in some detail. If we attentively² watch the action of the weather on a friable³ sea-cliff we notice that large pieces tumble at intervals⁴ on to the beach, and in due time these are washed away by the waves, thus encouraging more to fall when the time is ripe. This process of denudation⁵ each year takes tens of thousands of tons of sandy clays and the like from the beaches around our islands. Large pieces of rock, too, are detached by the weather, and eventually succumb⁶ to wave action. During storms large stones are hurled⁷ against the cliffs, and the general effect of this bombardment is to wear them away, and reduce them to powder and sand grains with all possible expedition. No one who has not seen the waves at work at such times can have any idea of their tremendous power of moving blocks of stone many tons in weight. During calm weather the slight movement of the waves on the beach is manufacturing tons and tons of sand. A mass of gravel⁸ falls from the cliff; the finer particles are floated away at the earliest opportunity; the angular stones have their rough projections⁹ knocked off by striking against each other; and the incessant¹⁰ movement up and down the beach slope reduces the rough stone to a pebble,23 all the time the particles thus shaved off are taken out to sea for greater or less distances. If the cliffs are of limestone¹¹, or similar rock, both chemical and mechanical methods of denudation come into play, and considerable quantities of lime, &c., are taken away by the sea water in suspension and solution. Large quantities of lime are daily added to the sea through the agency of rivers also.

Now, what becomes of these vast quantities of detritus¹² furnished to the sea? That depends on the shore currents at the particular locality. If there is not much of a current, the larger grains of grit¹³ and sand are soon separated from the rest, and fall to the bottom, whilst the clays are taken farther out to sea before being laid down. But, in any case, the reader will readily perceive that marine deposits must of necessity be on a grander scale, and of a much more substantial character, as a rule, than river, lacustrine, or estuarine¹⁴ deposits. By their mode of origin, too, they must be more homogeneous, whilst they are frequently several hundreds of feet in thickness. In their process of deposition¹⁵ they were not influenced by every storm and freshet; nothing short of great earth-movements in process of time, or some other equally grand phenomena¹⁶, could disturb the even tenour of their existence. How different to the comparatively insignificant¹⁷ strata¹⁸ formed by the other methods alluded¹⁹ to!

Take samples of brick-earth of fluviatile origin at intervals and analyse them; no two analyses will be alike, except by a most remarkable²⁰ coincidence—more by accident than otherwise. On the other hand, take a thick marine clay, and compare its chemical composition as ascertained²¹ at the present time with that of it made, say, 20 years ago in the same brickyard, and the analyses will, in most instances, be practically identical—at any rate, so far as they may be of use to the brickmaker.

24 A brickmaker using a marine clay possesses innumerable advantages over another employing brick-earths due to river action. It is no uncommon²² thing for a marine clay—say, 300 feet in thickness—to continue across country for hundreds of miles, stretching from the North of England to the South, and over into the Continent, save for the slight break occasioned by the scooping²³ out of the English Channel. The composition of the Oxford²⁴ Clay, from which the well-known bricks at Peterborough are made, does not differ in the slightest degree, so far as suitability for brickmaking is concerned, from the Oxford Clay of Bourges or Chateauroux, in the centre of France, or indeed at almost any other point en route. With marine beds it is possible to deal with the matter on broad lines, but it is not so with any other class of deposits.

If a marine clay in a specified²⁵ locality is found to be unsuitable for bricks at one point, by reason of the presence of too much lime, it would be a phenomenon if clay along the same geological horizon did not present the same unfavourable features at every other point within the district. The homogeneous composition, both from mineralogical and chemical standpoints, of thick marine clays renders them of special use to the brickmaker. Having by sundry²⁶ processes, after infinite labour, produced a certain class of brick from such an earth, he does not as a rule have to materially modify those processes as the earth is dug into to continue manufacturing the same brick. He is dealing²⁷ with an earth which, comparatively speaking, is a constant quantity—when the clays are thick, and no lines of bedding are distinctly visible.

We find that a rooted conviction exists in many brickyards that clays of marine origin are no good for brickmaking, because (so the opinion runs) they always25 contain so much salt. It is wonderful that such ignorance prevails, when the slightest acquaintance with the subject would teach otherwise. It is perfectly²⁸ true that such deposits might have contained salt during and for some time after deposition, but it is absurd to suppose that their marine origin has anything to do with the presence of common salt in the clay at the present time. Salt is soluble²⁹ in water, and has been removed from such clays by the percolation³⁰ of underground water in 99 cases out of a hundred. Indeed, as a matter of experience, we find that salt is most commonly found in beds of lacustrine origin, or those laid down in enclosed portions of the sea, for reasons we need not enter into at the present moment. Of course, when material is taken from the sea-shore to make into bricks, a considerable quantity of salt is manifest, but that is a totally different thing to the clays deposited—we should not like to say how many thousands of years ago. Clays of all kinds, however, may be impregnated with salt (as in parts of Cheshire), owing to the proximity³¹ of other beds containing that mineral; also by the percolation of underground water with much salt in solution.

To give some idea of the antiquity³² of the Oxford Clay alluded to—and that is quite a “young clay” geologically speaking—we may remark that at the time it was laid down not a single species of animal existed like those now living. The only mammals found, very small and very lowly organised, were like kangaroo rats; the birds were more like flying reptiles³⁴ than anything else; it was the age of reptiles, and enormous, unwieldy brutes³⁵ swam in the water or floundered about on land; huge sharks abounded³⁶, and armour-clad fish of kinds very different to those now existing roamed the sea; even26 the “shell-fish” were not altogether like modern ones; whilst the plants find their nearest modern analogues³⁷ in the wilds of Australasia. No elephants, tigers, lions, bears, or dogs lived then, and the face of Nature wore a totally different aspect to what obtains at the present time in any part of the globe.

And this seems a fitting opportunity to the writer to put on record the fact that many of the most wonderful remains³⁸ found in the Oxford Clay and the neighbouring Kimeridge Clay are due to the discoveries of brickmakers. Without their valuable aid scientists would be quite unable to clearly depict³⁹ the life of those remote epochs. We have mentioned Peterborough; some most interesting remains have been found in the clays near that town during the past few years. To appreciate this let the reader visit the fossil reptile³³ gallery of the British Museum (Natural History), at South Kensington. One of the most recent acquisitions, set up a year or two ago, is the skeleton of a young Plesiosaurus—without doubt the most perfect specimen⁴¹ in the world of its kind—from Peterborough. The Plesiosaurus was a large swimming reptile, with paddles, and a long neck.

We mention these things not only to instil⁴² philosophical⁴³ interest in such brick-earths, which may be reflected upon after business hours, but to impart some idea of the extreme remoteness of the epoch⁴⁰ from the human point of view, and to insist on the immensity of the intervening time throughout which circulating underground waters—even in such an impervious⁴⁴ material as stiff clay—may have exerted chemical action. The “mineralisation” of the fossils is an eloquent⁴⁵ witness of the effect of such changes. The reader will perceive from this that there is scant⁴⁶ possibility of soluble salts27 being present in such marine clays; and the geological circumstances are fully⁴⁷ borne out by the results of hundreds of chemical analyses of thick marine clays.

The invertebrate⁴⁸ fossils more particularly testify to the marine origin of the clays, and are thus invested with considerable practical interest. The man whose duty it is to determine the persistence⁴⁹, or otherwise, of valuable marine brick-earths has thus a much easier task than when called upon to decide the value of a large tract⁵⁰ of land for brickmaking purposes, of fluviatile origin. Finally, brick-earths do not, except in extremely rare instances, vary materially in character when dug into horizontally, thus every opportunity is afforded to the manufacturer for making an unvariable quality brick, tile, or drain pipe. It should be borne in mind, however, that these clays often weather a brown colour, which on being dug into changes to a bluish-black tint⁵¹, the latter being the unaltered and best portion as a rule. The only practical advantage the worker of a superficial river deposit possesses over his neighbour using thick marine clay is in the great range of variation in materials disclosed in the former kind of pit. By judiciously⁵² mixing the different beds he may be able to live well where the worker of marine clays, especially where the clay is too stiff, or contains too much lime, “comes to grief.” A good marine clay is a great boon⁵³, a bad one cannot be remedied other than by the sacrifice of much money.

1 marine   

adj.海的；海生的；航海的；海事的；n.水兵

参考例句：

• Marine creatures are those which live in the sea. 海洋生物是生存在海里的生物。
• When the war broke out,he volunteered for the Marine Corps.战争爆发时，他自愿参加了海军陆战队。

2 attentively   

adv.聚精会神地；周到地；谛；凝神

参考例句：

• She listened attentively while I poured out my problems. 我倾吐心中的烦恼时，她一直在注意听。 来自《简明英汉词典》
• She listened attentively and set down every word he said. 她专心听着，把他说的话一字不漏地记下来。 来自《简明英汉词典》

3 friable   

adj.易碎的

参考例句：

• The friable boxes arrived intact.这些易碎的箱子完整无损地运到了。
• The friable china survived the bumpy journey safe and sound.那批易碎的瓷器经过颠簸的旅途仍完好无损。

4 intervals   

n.[军事]间隔( interval的名词复数 )；间隔时间；[数学]区间；（戏剧、电影或音乐会的）幕间休息

参考例句：

• The forecast said there would be sunny intervals and showers. 预报间晴，有阵雨。
• Meetings take place at fortnightly intervals. 每两周开一次会。

5 denudation   

n.剥下；裸露；滥伐；剥蚀

参考例句：

• Sedimentation and denudation play a role in exceptional cases. 沉积和剥蚀作用的影响只在特殊情况下起作用。 来自辞典例句
• The cooling rate and denudation rate decreased overall from north to south. 总体上自北而南，剥蚀速率和冷却速率均逐渐变小。 来自互联网

6 succumb   

v.屈服，屈从；死

参考例句：

• They will never succumb to the enemies.他们决不向敌人屈服。
• Will business leaders succumb to these ideas?商业领袖们会被这些观点折服吗？

7 hurled   

v.猛投，用力掷( hurl的过去式和过去分词 )；大声叫骂

参考例句：

• He hurled a brick through the window. 他往窗户里扔了块砖。
• The strong wind hurled down bits of the roof. 大风把屋顶的瓦片刮了下来。 来自《简明英汉词典》

8 gravel   

n.砂跞；砂砾层；结石

参考例句：

• We bought six bags of gravel for the garden path.我们购买了六袋碎石用来铺花园的小路。
• More gravel is needed to fill the hollow in the drive.需要更多的砾石来填平车道上的坑洼。

9 projections   

预测( projection的名词复数 )； 投影； 投掷； 突起物

参考例句：

• Their sales projections are a total thumbsuck. 他们的销售量预测纯属估计。
• The council has revised its projections of funding requirements upwards. 地方议会调高了对资金需求的预测。

10 incessant   

adj.不停的，连续的

参考例句：

• We have had incessant snowfall since yesterday afternoon.从昨天下午开始就持续不断地下雪。
• She is tired of his incessant demands for affection.她厌倦了他对感情的不断索取。

11 limestone   

n.石灰石

参考例句：

• Limestone is often used in building construction.石灰岩常用于建筑。
• Cement is made from limestone.水泥是由石灰石制成的。

12 detritus   

n.碎石

参考例句：

• Detritus usually consists of gravel, sand and clay.岩屑通常是由砂砾，沙和粘土组成的。
• A channel is no sooner cut than it chokes in its own detritus.一个河道刚被切割了不久，很快又被它自己的碎屑物质所充塞。

13 grit   

n.沙粒，决心，勇气；v.下定决心，咬紧牙关

参考例句：

• The soldiers showed that they had plenty of grit. 士兵们表现得很有勇气。
• I've got some grit in my shoe.我的鞋子里弄进了一些砂子。

14 estuarine   

河口的，江口的

参考例句：

• The water above the continental shelf is moved by the tides and by estuarine currents. 潮流和河口流使大陆架上的海水流动。
• An outstanding example of the drastic alteration of the estuarine environment is found in the Netherlands. 河口湾环境发生强烈变化的一个突出的例子是荷兰。

15 deposition   

n.免职，罢官；作证；沉淀；沉淀物

参考例句：

• It was this issue which led to the deposition of the king.正是这件事导致了国王被废黜。
• This leads to calcium deposition in the blood-vessels.这导致钙在血管中沉积。

16 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。

17 insignificant   

adj.无关紧要的，可忽略的，无意义的

参考例句：

• In winter the effect was found to be insignificant.在冬季，这种作用是不明显的。
• This problem was insignificant compared to others she faced.这一问题与她面临的其他问题比较起来算不得什么。

18 strata   

n.地层（复数）；社会阶层

参考例句：

• The older strata gradually disintegrate.较老的岩层渐渐风化。
• They represent all social strata.他们代表各个社会阶层。

19 alluded   

提及，暗指( allude的过去式和过去分词 )

参考例句：

• In your remarks you alluded to a certain sinister design. 在你的谈话中，你提到了某个阴谋。
• She also alluded to her rival's past marital troubles. 她还影射了对手过去的婚姻问题。

20 remarkable   

adj.显著的，异常的，非凡的，值得注意的

参考例句：

• She has made remarkable headway in her writing skills.她在写作技巧方面有了长足进步。
• These cars are remarkable for the quietness of their engines.这些汽车因发动机没有噪音而不同凡响。

21 ascertained   

v.弄清，确定，查明( ascertain的过去式和过去分词 )

参考例句：

• The previously unidentified objects have now been definitely ascertained as being satellites. 原来所说的不明飞行物现在已证实是卫星。 来自《简明英汉词典》
• I ascertained that she was dead. 我断定她已经死了。 来自《简明英汉词典》

22 uncommon   

adj.罕见的，非凡的，不平常的

参考例句：

• Such attitudes were not at all uncommon thirty years ago.这些看法在30年前很常见。
• Phil has uncommon intelligence.菲尔智力超群。

23 scooping   

n.捞球v.抢先报道( scoop的现在分词 )；（敏捷地）抱起；抢先获得；用铲[勺]等挖（洞等）

参考例句：

• Heated ice cream scoop is used for scooping really cold ice cream. 加热的冰淇淋勺是用来舀非常凉的冰淇淋的。 来自互联网
• The scoop-up was the key phase during a scooping cycle. 3个区间中，铲取区间是整个作业循环的关键。 来自互联网

24 Oxford   

n.牛津（英国城市）

参考例句：

• At present he has become a Professor of Chemistry at Oxford.他现在已是牛津大学的化学教授了。
• This is where the road to Oxford joins the road to London.这是去牛津的路与去伦敦的路的汇合处。

25 specified   

adj.特定的

参考例句：

• The architect specified oak for the wood trim. 那位建筑师指定用橡木做木饰条。
• It is generated by some specified means. 这是由某些未加说明的方法产生的。

26 sundry   

adj.各式各样的，种种的

参考例句：

• This cream can be used to treat sundry minor injuries.这种药膏可用来治各种轻伤。
• We can see the rich man on sundry occasions.我们能在各种场合见到那个富豪。

27 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。

28 perfectly   

adv.完美地，无可非议地，彻底地

参考例句：

• The witnesses were each perfectly certain of what they said.证人们个个对自己所说的话十分肯定。
• Everything that we're doing is all perfectly above board.我们做的每件事情都是光明正大的。

29 soluble   

adj.可溶的；可以解决的

参考例句：

• These tablets are soluble in water.这些药片可在水中溶解。
• Camphor is soluble in alcohol.樟脑在酒精中可以溶化。

30 percolation   

n.过滤，浸透；渗滤；渗漏

参考例句：

• This corresponds to the percolation phase of the drying mechanism. 这相当于干化机理的渗滤阶段。 来自辞典例句
• The percolation clusters with various occupying probability are constructed. 构造了具有不同占据概率的逾渗集团。 来自互联网

31 proximity   

n.接近，邻近

参考例句：

• Marriages in proximity of blood are forbidden by the law.法律规定禁止近亲结婚。
• Their house is in close proximity to ours.他们的房子很接近我们的。

32 antiquity   

n.古老；高龄；古物，古迹

参考例句：

• The museum contains the remains of Chinese antiquity.博物馆藏有中国古代的遗物。
• There are many legends about the heroes of antiquity.有许多关于古代英雄的传说。

33 reptile   

n.爬行动物；两栖动物

参考例句：

• The frog is not a true reptile.青蛙并非真正的爬行动物。
• So you should not be surprised to see someone keep a reptile as a pet.所以，你不必惊奇有人养了一只爬行动物作为宠物。

34 reptiles   

n.爬行动物，爬虫( reptile的名词复数 )

参考例句：

• Snakes and crocodiles are both reptiles. 蛇和鳄鱼都是爬行动物。 来自《简明英汉词典》
• Birds, reptiles and insects come from eggs. 鸟类、爬虫及昆虫是卵生的。 来自《现代汉英综合大词典》

35 brutes   

兽( brute的名词复数 )； 畜生； 残酷无情的人； 兽性

参考例句：

• They're not like dogs; they're hideous brutes. 它们不像狗，是丑陋的畜牲。
• Suddenly the foul musty odour of the brutes struck his nostrils. 突然，他的鼻尖闻到了老鼠的霉臭味。 来自英汉文学

36 abounded   

v.大量存在，充满，富于( abound的过去式和过去分词 )

参考例句：

• Get-rich-quick schemes abounded, and many people lost their savings. “生财之道”遍地皆是，然而许多人一生积攒下来的钱转眼之间付之东流。 来自英汉非文学 - 政府文件
• Shoppers thronged the sidewalks. Olivedrab and navy-blue uniforms abounded. 人行道上逛商店的人摩肩接踵，身着草绿色和海军蓝军装的军人比比皆是。 来自辞典例句

37 analogues   

相似物( analogue的名词复数 )； 类似物； 类比； 同源词

参考例句：

• A vegetarian gets protein not from meat but from its analogues. 素食者所摄取的蛋白质不是来自肉类而是来自近似肉类的食物。
• Moreover, it tends to foster the human qualities that I admire most-courage and its analogues. 不但如此，它还能培养我最景仰的那些德性-勇敢和诸如此类的东西。

38 remains   

n.剩余物，残留物；遗体，遗迹

参考例句：

• He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
• The remains of the meal were fed to the dog.残羹剩饭喂狗了。

39 depict   

vt.描画，描绘；描写，描述

参考例句：

• I don't care to see plays or films that depict murders or violence.我不喜欢看描写谋杀或暴力的戏剧或电影。
• Children's books often depict farmyard animals as gentle,lovable creatures.儿童图书常常把农场的动物描写得温和而可爱。

40 epoch   

n.(新)时代；历元

参考例句：

• The epoch of revolution creates great figures.革命时代造就伟大的人物。
• We're at the end of the historical epoch,and at the dawn of another.我们正处在一个历史时代的末期，另一个历史时代的开端。

41 specimen   

n.样本，标本

参考例句：

• You'll need tweezers to hold up the specimen.你要用镊子来夹这标本。
• This specimen is richly variegated in colour.这件标本上有很多颜色。

42 instil   

v.逐渐灌输

参考例句：

• It's necessary to instil the minds of the youth with lofty ideals.把崇高理想灌输到年青人的思想中去是很必要的。
• The motive of the executions would be to instil fear.执行死刑的动机是要灌输恐惧。

43 philosophical   

adj.哲学家的，哲学上的，达观的

参考例句：

• The teacher couldn't answer the philosophical problem.老师不能解答这个哲学问题。
• She is very philosophical about her bad luck.她对自己的不幸看得很开。

44 impervious   

adj.不能渗透的，不能穿过的，不易伤害的

参考例句：

• He was completely impervious to criticism.他对批评毫不在乎。
• This material is impervious to gases and liquids.气体和液体都透不过这种物质。

45 eloquent   

adj.雄辩的，口才流利的；明白显示出的

参考例句：

• He was so eloquent that he cut down the finest orator.他能言善辩，胜过最好的演说家。
• These ruins are an eloquent reminder of the horrors of war.这些废墟形象地提醒人们不要忘记战争的恐怖。

46 scant   

adj.不充分的，不足的；v.减缩，限制，忽略

参考例句：

• Don't scant the butter when you make a cake.做糕饼时不要吝惜奶油。
• Many mothers pay scant attention to their own needs when their children are small.孩子们小的时候，许多母亲都忽视自己的需求。

47 fully   

adv.完全地，全部地，彻底地；充分地

参考例句：

• The doctor asked me to breathe in,then to breathe out fully.医生让我先吸气，然后全部呼出。
• They soon became fully integrated into the local community.他们很快就完全融入了当地人的圈子。

48 invertebrate   

n.无脊椎动物

参考例句：

• Half of all invertebrate species live in tropical rain forests.一半的无脊椎动物物种生活在热带雨林中。
• Worms are an example of invertebrate animals.蠕虫是无脊椎动物的一个例子。

49 persistence   

n.坚持，持续，存留

参考例句：

• The persistence of a cough in his daughter puzzled him.他女儿持续的咳嗽把他难住了。
• He achieved success through dogged persistence.他靠着坚持不懈取得了成功。

50 tract   

n.传单，小册子，大片(土地或森林)

参考例句：

• He owns a large tract of forest.他拥有一大片森林。
• He wrote a tract on this subject.他曾对此写了一篇短文。

51 tint   

n.淡色，浅色；染发剂；vt.着以淡淡的颜色

参考例句：

• You can't get up that naturalness and artless rosy tint in after days.你今后不再会有这种自然和朴实无华的红润脸色。
• She gave me instructions on how to apply the tint.她告诉我如何使用染发剂。

52 judiciously   

adv.明断地，明智而审慎地

参考例句：

• Let's use these intelligence tests judiciously. 让我们好好利用这些智力测试题吧。 来自《简明英汉词典》
• His ideas were quaint and fantastic. She brought him judiciously to earth. 他的看法荒廖古怪，她颇有见识地劝他面对现实。 来自辞典例句

53 boon   

n.恩赐，恩物，恩惠

参考例句：

• A car is a real boon when you live in the country.在郊外居住，有辆汽车确实极为方便。
• These machines have proved a real boon to disabled people.事实证明这些机器让残疾人受益匪浅。