1.Do you know where clay comes from？If you take a long walk near the town in which you live，you will very likely find some deep hole or pit in the ground from which men are digging out the stuff we call clay.
A POTTER AT WORK（陶工在工作）
2.Clay is found in thick beds or layers in the earth，and we may therefore call it a rock.We may also call it a mineral.
3.Let us ask the men in the clay-pit to give us a lump of clay.Its colour will most likely be brown.Pure clay is white，but a little red iron-rust is often found mixed with it.As we press the clay between our fingers，we find that we can mould or knead it into any shape we please.
4.Let us make the clay into a ball.Now let us try to play a game of cricket with our clay ball.We shall soon find that the clay ball will not bounce as the leather ball does.
5.When we press a piece of clay out of shape，it does not spring back to its old shape again as a ball made of leather or of india-rubber does.We therefore say that clay is not elastic.
6.We shall next put our lump of clay in the oven，and let it dry for several hours.The dry clay will break into powder，if we drop it on the ground；so we say that dry clay is brittle.
7.But let us put the dry clay into a saucer half full of water.Soon all the water will disappear，while the clay will become soft once more.What has become of the water？Dry clay is full of tiny pores，and it has sucked up the water into its pores.
8.Now let us mould our lump of soft clay into the form of a cup，and fill it with water.The water does not soak through the clay，for all its pores are already full of water.Now you see whyclay is used to line the bottoms and sides of ponds and canals①.
Clay will not let water pass through it：it is waterproof②.
9.Let us mould another lump of clay into the shape of a brick.We shall take this lump of clay to a brick-maker，and ask him to bake it for us in his kiln③.There it will become a hard red block like a brick，which would be very usefulin helping to build a house.ROOFING-TILE AND DRAIN-PIPE（瓦片和渗水管）①Canals，waterways made for boats or ships.
②Waterproof，proof against water；that will not let water pass through.
③Kiln （kil），a furnace for burning lime，baking bricks，etc.
10.Drain-pipes①，tiles②，chimney-pots，and many other articles are made of baked clay.Clay burned in rough lumps is sometimes used for making roads and foot-paths.It soaks up the rain-water，and so keeps the road dry.
11.Jugs and basins and cups and saucers are also made of baked clay.These vessels must not be porous③，or they will let the liquids escape which we put into them.The pores of such articles are filled up by dipping them into a mixture that makes them smooth like glass.
12.A man who makes vessels out of clay is called a potter.He has aflat wheel in front of him on which he places the soft lump of clay，and as it spins round he moulds it with his hands into any shape he likes.Dishes made of clay are called pottery or earthenware.
SUMMARY
Clay is called a rock because it is found in thick beds or layers in the earth.It is waterproof when wet，and when dry it is very brittle.Baked clay is made into bricks，drain-pipes，tiles，chimney-pots，etc.It is also used for making roads and footpaths.Cups and saucers，jugs and basins，are also made from baked clay，by a man called a potter.
①Drain-pipes，pipes which carry off water from fields or houses.
②Tiles，pieces of baked clay used in roofing houses，etc.
③Porous，full of pores or very small openings.
【中文阅读】
1．你知道粘土是从哪儿来的吗？如果你在居住的城镇附近走上一段很长的路，就很可能发现地上有一些深洞（hole）或者深坑（pit），人们就是从这些洞里，把一种叫“粘土”的东西挖出来的。①2．粘土在一些很厚的泥土层中可以找到，我们也可以管粘土叫“岩石”
（rock）或者“矿物”（mineral）。3．咱们朝挖粘土的人要一块粘土吧。粘土的颜色大部分是棕色的。纯粹的粘土是白色的，但经常混有少量的红色铁锈。我们把粘土放在手指之间捻一下，发现可以把它“塑成”（mould）或者“捏成”（knead）任何我们想要的形状。②4．咱们把粘土团成一个球吧，用这个粘土球来玩玩板球！我们很快就会发现，粘土球不会像皮球那样弹跳。③5．我们把一块粘土捏得变形之后，粘土不会弹回原来的形状，而皮子或者天然橡胶做的球，就可以弹回原来的形状。所以我们说，粘土“没有弹性”。
6．然后，我们把那个粘土大块，放进炉子里，烤上几个小时。干燥的粘土，一掉到地上就会碎成粉末。所以我们说，粘土很“脆”，脆的英语是brittle。④7．不过，咱们再把干燥的粘土，放进盛了一半水的碟子里。用不了多久，所有的水就都不见了，而粘土又会变软了。水上哪儿去了？干燥的粘土满是细小的孔洞，把水都吸到孔洞里去了。
8．咱们再把这个软软的粘土大块，塑成一只杯子的形状，盛满水。水是不会渗过粘土的，因为粘土的孔洞已经盛满了水。现在你就知道，人们为什么用粘土，来铺在池塘和水渠的底下和侧面了，因为粘土不会让水透过去，粘土是“防水的”（waterproof）。⑤9．咱们把另一大块粘土塑成砖的形状，把这块粘土拿给烧砖的工人，让他在砖窑（kiln）里给我们烧一遍。这样，粘土就会变成一种暗红色的块儿，跟砖一样。这种粘土，在修建房子的时候非常有用。⑥10．渗水管、瓦片、烟筒的管帽，还有很多其他的物件，都是烧制的粘土做的。⑦烧过的粘土大块，有时候用来修建街道和人行道。粘土能把雨水吸干净，让道路保持干燥。⑧11．水壶、脸盆、杯子、碟子也是烧过的粘土做的，但是这些器皿可不能“渗透”，不然盛上液体就会漏出去。“有渗透性”的英语是porous。这种材料里的小孔，是浸在一种混合物里才堵上的，这种混合物，能让粘土像玻璃一样光滑。⑨12．用粘土制作器皿的人叫“陶工”（potter），⑩陶工前面有一个扁平的轮子，他把软粘土放在上面，轮子一边转，他就一边用手，把粘土塑造成他想要的形状。粘土做的器皿统称陶器（pottery或earthenware）。
译注
①“粘土”也写成“黏土”，主要成分是“含水铝硅酸盐”。形成粘土的矿物有高岭石、蒙脱石、水云母等，此外粘土中还含有石英等杂质。
②粘土的这种特性叫“可塑性”。粘土的可塑性，来自粘土中极小的片状颗粒（小于5微米）。纯粹的粘土叫高岭土，也叫瓷土，就是文中所说的白色，多用来制造瓷器。随着杂质含量的增高，粘土还分为“耐火粘土”（10%以下）、“难熔粘土”（10%-15%）、“易熔粘土”（25%），最后一种粘土就是第9段里所说的暗红色硬块儿，也是烧砖的主要材料。
③板球的英语是cricket，是一种两队各11人的对抗运动，用板子形状的球拍来击打皮球。在英国和澳大利亚、新西兰等英联邦国家很流行，在中国还处于起步阶段。2006年，中国举办了第一次全国板球锦标赛。2012年5月，中国的六名板球国家队选手，还去了英国参加培训。
④这个词我们在前面见过，还记得是用来描述什么的吗？粘土在加热到110摄氏度的时候，粘土孔洞里的水，也就是“自由水分”，就会完全蒸发，让粘土失去可塑性。
⑤现在，为了防止池塘渗漏，除了铺粘土之外，还可以铺膨润土和塑料薄膜。
⑥用专业术语说，这是“粘土焙烧之后成为石质材料”的特性，下一课会详细介绍。
⑦现代工业中，粘土还有很多其他的用途：处理放射性物质、制造颜料、制作复合材料、吸收水中的污染物等等。
⑧这就是所谓的“砖砌路”，一般都是在一个城镇以内的路面。在沥青路和水泥路出现之后，砖砌路变得很少见了。中国的新疆若羌县境内，国道218线，有一段1966年建造的砖砌公路，经历了30多年严苛条件的考验，目前已经成为了一个观光点。
⑨这个步骤应该是陶器的“上釉”。名词“釉”和动词“上釉”的英语都是glaze。“釉”是用矿物原料和化工原料配成的一种浆液，利用坯体的吸水性，可以让釉附着在上面，这样就能让坯体表面形成一种类似玻璃的薄层，是把陶器加工成瓷器的关键一步，可以提高瓷器强度，让瓷器更加美观。最常见、效率最高的上釉法是文中所说的“浸釉”，此外还有“浇釉”、“吹釉”等等。
⑩居然跟哈利·波特的姓氏一样。其实，英语里还有很多姓氏是职业的名字，比如Smith是“铁匠”，Mason是“石工”，等等。
HOW BRICKS ARE MADE
