作者：(美)文森特·默奇
出版社：天津人民出版社
格式: AZW3, DOCX, EPUB, MOBI, PDF, TXT
科学读本·英文原版(套装共6册)试读：
科学读本(英文原版)(第1册)
Foreword
This series of Science Readers was published for the use of teachers and students. It will be found useful,not only in those schools in which Elementary Science is taken as a class subject,but also for the purposes of an ordinary reader.
Of this series of Science Readers,Books I,II,and III are adapted to pupils who are in their third and fourth years of school work. Both the reading and the subject matter of Books IV,V,and VI are suitable for Senior Grades.
It is hoped that the young readers who follow them through these lessons will catch something of the enthusiasm and earnestness which characterize them as they advance step by step from very small beginnings to a real understanding of the elementary facts of natural science.
The subject matter in this volume is intended for higher level students,and includes not only a more in-depth study of the natural sciences,but also attempts to inform the student as to the connection between scientific advances and economic growth.
At the time of this series？ original publication,economic matters were often discussed in British standards;therefore,the student will find that in the later volumes of the Elementary Science Readers,British economics and manufactures are discussed quite frequently. This held true even for the American students who originally used these readers as a textbook to accompany their Elementary Science class studies.
Furthermore,in the nineteenth and early twentieth centuries,hunting,fur-and ivory-trading,and deforestation had become highly developed industries of commerce,to the point where rampant and indiscriminate activities had caused great devastation to the natural world. In modern times,we seek to conserve the natural world,and have put in place protection and preservation laws that are respected and strongly adhered to around the globe; therefore,the reader must approach the lessons dealing with this subject matter with an open mind,and an understanding that this type of activity,while unfortunate,remains a part of history and should be addressed as such.
In spite of some of the inevitable discrepancies between the modern world and the one in which this series was originally published,these science readers remain an excellent source of knowledge of the fundamental facts of the natural sciences,and the enthusiasm and earnestness which characterize these lessons are sure to draw the reader in.
Lesson 01 Water
Fred and his cousin Willie were two smart boys in the same class at school. They were only little boys,but they were fond of their school and their lessons.
They used to play at school in the evening with Fred’s little sister Norah.
Their teacher was giving the class jolly lessons on some of the common things around them. These were not at all like the other lessons of the day. Teacher gave them to the class as a treat. The boys soon began to look forward to them,as the best of all their lessons.
Norah,too,liked to hear all about them from the boys. It was great fun to sit around the fire in the evening,and chat over the lessons of the day.
The irst lesson was about water.
“What do you think,Norah？” said Fred one evening. “Teacher began to talk to us about water,by showing us a saucer full of sawdust.
“He piled up the sawdust in a heap in the saucer,and then tried to do the same with some water in another saucer.”
“But,of course,he couldn’t do it,” said Willie,“because you can’t make water stand up in a heap. It always keeps a lat or level surface.”
“Yes; and,when it got to the top of the saucer,it ran away over the sides,and on to the table,” added Fred. “We saw it low along the table,and fall down to the ground.”
“Why,of course,” said Norah,“water always lows down. We can see it flow down,if we turn on the tap. It never lows up.”
“Teacher told us to think of the rain,too,” said Willie. “The drops of rain always fall down—never up.”
“I can show you some drops of water.” said Fred.“Look; I dip this brush in the water,and shake it.The water will fall from the brush in little round drops.”
SUMMARY
We cannot pile up water in a heap; it always keeps a level surface. Water breaks up into little drops,and flows about.Water always flows down.
Lesson 02 Water—A Liquid
Norah’s mother called her away to mind the baby,before the boys had told her all about their lesson.
She came back as soon as she could,and they began to chat again.
“I wonder whether Norah forgets what we learned about water,” said Fred.
“No,” said Norah,“I don’t forget. I know that water lows,and it always lows down. It keeps a lat surface,and it cannot stand in a heap. It breaks up into round drops,but the drops will run together again,and make a pool of water.”
“Quite right,” said Fred. “But now I’m going to puzzle you. Can you tell me what shape water is？
“Teacher tried to puzzle us; didn’t he,Will？ But he soon made it clear. He showed us the saucer,and we saw that it was round. Then he filled it with water,and of course it was easy to see that the water in the saucer was round too.”
“But the water did not remain round,” said Willie,“for teacher next poured it out of the saucer into a square tin box.”
“I know.” said Norah,“it became square then,like the box.”
“Right,” replied Fred,“and then we saw the water poured out of the box into a tumbler; out of the tumbler into a jug; out of the jug into a bottle. It took the shape of the new vessel each time.
“Can you think of any other things,Norah,that would do as water does？”
“I know some,” said Norah. “Milk and oil,vinegar and tea would do the same.”
“Now,Norah,” said both boys at once,“you must try not to forget the proper name for all these things. Teacher tells us to call them liquids.
“Liquids l ow about,break up into drops,take the shape of the vessel which holds them,and cannot stand in a heap,but always keep a level surface.”
SUMMARY
Water has no shape of its own. It always takes the shape of the vessel which holds it. Water,milk,oil,and vinegar are liquids.
Lesson 03 Solids
“You know what happens,Norah,when I pour water on the table.”
“Oh yes,”replied Norah; “it lows about,because it is a liquid.”
“Now I will put this stone on the table. Will the stone low away too？”
“No,” said Norah,“it will stand where you place it.”
“Then would it be right to call the stone a liquid？” said Fred.
“No,it cannot be a liquid,for all liquids low.”
“We know we can’t pick up water,” said Fred. “It would run through our ingers,and fall in drops on the loor.
“But we can pick up the stone without spilling any of it.”
“Yes,” said Willie,“and we might shake the stone ever so long,but we could not shake drops from it,as we did from the water in the brush.”
“I say,Will,” said Fred,“wasn’t it funny when teacher shook the saw-dust into the basin,and asked one of the boys to pick out the piece of wood？”
“Yes,” said Will,“but there was no piece of wood in the basin,for the little bits of saw-dust do not run together,as the drops of water do.”
“I think,” said Norah,“I can tell you something else. Water and all other liquids have no proper shape. But if we look at this stone,this brick,or this piece of wood,we can see that each of them has a shape of its own.”
“We know that,when we put some water into the basin,it spreads out to ill it,” said Fred.
“Yes,” said Norah,“it takes the shape of the basin,and it keeps a level surface.”
“Now watch,while I put this brick into the basin.Does it spread out to ill the basin,Norah？”
“No,” said Norah.
“Does it take the shape of the basin？”
“No.”
“Teacher gave us the proper name for things like the brick and the piece of wood,” said Willie. “We call them solids.
“Solids are bodies that do not low,do not break up into drops,have a shape of their own,and do not take the shape of the vessel which holds them.”
SUMMARY
Solids do not flow about,and do not fall away in drops,as water does. They do not take the shape of the vessels which hold them,but have a shape of their own.
Lesson 04 Liquids and Solids
When the boys,a few nights later,called Norah to come and play school,Fred said: “I want to be teacher this time. I am going to show Norah what we have been doing in school to-day. Mother gave me this piece of wax,and said I might have this old iron spoon.
“Now I will put the wax into the spoon,” said Fred. “See; it stands in the middle of the spoon.
“I want you to watch what happens,when I hold the spoon over the ire.”
“Why,the solid wax is changing into a liquid,”said Norah.
“How do you know it is a liquid,Norah？”
“It does not stand up in a lump in the middle of the spoon,as it did at first,” said Norah. “It flows about in the spoon. It keeps a level surface.”
“See,” said Fred,“I will pour some of it into this pill-box,just as teacher did today,and stand the box on the table.”
“That is just what we saw,Norah,when the meat was roasting the other day,” said Will.
“Yes,” said Norah,“the solid fat was changed into liquid,and fell in drops into the dish. I took it up in the spoon,and poured it over the meat to baste it.”
“Don’t you two children chatter so,”said Fred. “I want to have a look at our pill-box.
“See,Norah,the wax is cool now. It does not low about,even if we turn it upside down. It is not a liquid now.
“Suppose I cut the box open.”said Fred. “Look;here is a round piece of solid wax,the very shape of the box.”
“Why,Fred,” said Norah,“this proves that liquids do really take the shape of the vessels which hold them.”
“Quite right,clever little sister,” said Fred. “Now tell me what mother does with the liquid fat in the dripping-pan.”
“She pours it into a basin,” said Norah; “When it is cold she turns it out as solid dripping,just the shape of the basin.”
“I saw some solid water in a basin the other day.”said Will. “We call it ice. The cold weather changed the water into ice. When I put the basin on the hearth,the solid ice turned into water again.”
“You can’t change everything like this,” said Fred.
“No,” said Norah,“we can’t change brick,wood,stone,or slate into liquids.”
SUMMARY
Wax is a solid. We can change it into a liquid over the i re.The fire melts the wax. When it gets cold it becomes solid again. Ice is solid water.
Lesson 05 The Cat
“How snug and cozy puss looks in front of the fire,mother.”
The children had just been out for a run,and it was Norah who spoke. “What a quiet,gentle pussy cat it is,” she went on.
“Ah,” said her mother,“she wouldn’t be very quiet or very gentle if a mouse were to run out of its hole.”
“No,” said Willie. “I saw her catch a bird in the garden today. She was fierce and angry then. She tore it to pieces and ate it,after she had killed it.”
“What makes her so cruel sometimes？”asked Norah. “Can’t we teach her better,mother？”
“No,” said Fred,“we can’t; she kills and eats other animals because she was made for it,and meant for it.
“We had a ine lesson at school about the cat today. I’ll tell you all I can about it. Shall I,Norah？”
“Do,please,” said his sister.
“Then take puss on your lap,Norah,and we’ll begin,” said he. “First look at her eyes. Now look into my eyes. You see that round black spot in the middle of my eye？ That is the pupil of the eye.Light enters the eye through the pupil. The pupil of the cats eye is not like ours. In the bright light it is a long narrow slit; when it is dark the pupil opens into a very wide round window.”
“I suppose,” said Norah,“that is to help her to see when it is dark.”
“It is,” said Fred. “She wants to see well then,for the mice come out of their holes at night.
“Look at her now while she is stretching herself.What a wide mouth she has,and what long sharp teeth. Four of the teeth,two in each jaw,are much larger and stronger than the rest. Teacher says they are meant for seizing and tearing the mice and birds. We move our jaw from side to side,as well as up and down,when we chew our food. The cat’s jaw cannot move side-ways,it moves only up and down. Her jaws as well as her teeth are meant for cutting,not for chewing.
“I wonder whether the cat will let us look at her tongue？ Try and open her mouth,Will.” But the cat began to growl and look so savage that they had to give it up.
“Well,”said Fred,“teacher tells us that even the tongue is meant to help the cat in her flesheating. It is not smooth,like our tongue. It is set with small,sharp,horny points which stretch backwards. The cat uses her rough tongue to strip the lesh from the bones.”
SUMMARY
The cat is made to kill and eat other animals. It has a wide mouth,with four great pointed teeth for seizing its prey. All the teeth have sharp,jagged points fit for cutting through flesh.None of them are made for chewing. The jaw moves only and down. The tongue is rough. The cat’s eyes have a curtain in front. The curtain opens wide when it is getting dark,so that the cat can see well when other animals cannot see at all. In the daytime the curtain closes,and the pupil of the eye is only a narrow slit.
Lesson 06 More about the Cat
The next evening,as soon as they sat down,Fred began by asking Norah to tell all she could about the cat.
“All we have seen,” said he,“shows us that the cat was made to kill other living things and feed on their lesh. Even the cat’s eyes are meant to help her to catch her prey in the dark.
“Now,sometimes it is so dark that the cat herself can’t see. She has to feel her way. How do you think she does this,Norah？” Norah was puzzled.
“Look,” said Fred,“at that bare patch on each side of the cat’s mouth. Her long stif whiskers grow out from those patches. The cat feels her way along with the ends of these whiskers.
“Now,little girl,” he went on,“we are going to look at the cat’s feet. The front paws have five toes,the hind ones have four. she walks on her toes,not on her whole foot,as we do.
“Look on the under side of the paws and you will see that they all have soft smooth pads. The cat walks on these pads.”
“Oh,I see,” said Norah. “if the cat made a noise with her feet the mice would hear her and run away.So she has pads to walk on.”
“Teacher pointed out to us,”said Fred,“the loose,springy body,with its soft coat of fur,almost like velvet. All this is to help the cat to move quickly,and at the same time softly and quietly. She treads very lightly and softly.
“Now,one more look at her feet.If we took the cat up when she was angry,we should see that each toe is armed with a strong,curved,pointed claw.
“We don’t see them now; she keeps them drawn up in a sheath. She only stretches them out when she is angry.”
“It is these sharp claws,I suppose,” said Norah,“that help to seize the mouse,when she springs upon it.”
SUMMARY
The cat’s whiskers help it to feel its way when it is too dark to see. The cat walks on its toes,and the toes are padded,so that they do not make any sound as they tread. There are ive toes on the front paws and four on the hind ones. Each toe has a strong,sharp claw for seizing the prey. The cat keeps its claws drawn up in a sheath,except when it is angry.
Lesson 07 Hard and Soft Bodies
“We had a lesson today,” said Fred,“about solid bodies—some hard and some soft. Teacher showed us that we can call a body hard or soft only when we set it side by side with some other body.
“This is how he did it. He put an apple and a turnip on the table,and side by side with them,pieces of chalk,cork,wood,lead,iron,flint,steel,and glass. Then he set one of the boys to try and scratch these things with his nail,one after the other. He could pick pieces out of the turnip and the apple; he could scratch the chalk,cork,wood,and lead; but he could not make the least mark on the iron,lint,steel,or glass.”
“I see,” said Norah. “then this shows that the iron,steel,lint,and glass are harder than the wood and the lead; and that the wood and the lead are harder than the apple and the turnip.”
“You are a sharp little sister,” said Fred,“and you are quite right.
“Teacher next gave the boy a knife,and asked him to cut these things. He could cut little pieces off the lead and the wood,but he could not even scratch the steel,lint,or glass.”
“That was a good way,Fred,” said Willie,“to ind out which were the hardest things,by rubbing them one against another.”
“Yes,” said Fred,“the steel,flint,and glass rub pieces out of the wood and the lead,because they are harder than the wood and lead.
“The steel knife made a scratch on the iron,because it is harder than iron,but it could not scratch the glass.
“The wood and the lead rub pieces out of the chalk and cork,because they are harder than chalk and cork.
“And the chalk and cork rub pieces out of the apple and the turnip,because they are harder than the apple and turnip.”
“Glass must be very hard,” said Will. “A steel knife will not even scratch it.
“Teacher showed us that we can just manage to scratch glass with a sharp bit of lint,but we cannot cut it with lint.”
“I’ve seen a man cut glass,” said Norah.
“Yes,dear,” said Will,“but he cuts it with a diamond,and diamond is the hardest of all bodies.”
SUMMARY
Diamond is the hardest of all bodies. It will cut glass. A steel knife will not even scratch glass. Steel is harder than iron; iron is harder than lead; wood is harder than cork. The hard body will scratch a soft one.
Lesson 08 Porous Bodies
“I wish,” said Fred,“every fellow in my class had a jolly little sister,like I’ve got,to play school in the evenings.
“We had a fine lesson on a sponge today. Would you like us to tell you all about it,Norah？”
“That I should,” said his sister.
“Come along then,” said Fred. “I’ve got the sponge ready. I will stand it in a saucer of water,just as teacher did.
“Now Norah shall take it out of the saucer and put it on the table.
“What have you done with the water in the saucer,Norah？ It is all gone; the saucer is empty.”
“Bring me the sponge. Now squeeze it over the saucer.”
“Oh,I see,” said Norah. “The water all went up into the sponge.”
“Yes,little girl,” said Fred. “And now we will see how it got there.
“If you look at the sponge,you will find that there are little holes all over it.
“I will cut a piece of it away,and we shall see that the holes are not on the outside only,but all through the sponge. The sponge is full of holes.Will knows the proper name for these little holes.”
“Oh yes,” said Willie,“teacher told us to call them pores; and as the sponge is full of pores,we say it is porous.”
“Then I suppose,” said Norah,“the sponge sucks up the water because it is porous; the water ills up the holes in it.”
“Right,” said Fred. “Here is a piece of bread. If I stand it in the saucer with only a little water in the bottom,the bread will soon be wet all through.”
“The bread,like the sponge,is porous,” said Norah. “I can see the holes in it.”
“Yes,” said Willie,“but teacher showed us that some things may be porous although we cannot see the pores.”
“How did he do that？” said Norah.
“He put a piece of lump sugar and a piece of chalk into a plate,with a little red water in the bottom,” said Willie. “We couldn’t see any pores in the sugar or the chalk,but we saw the red water go up. That proves that there must be pores in them,and that sugar and chalk are both porous bodies.”
“Teacher gave us a long word to think about.”said Fred. “The word is absorb,and it means to suck up.
“He says all porous bodies absorb or suck up liquids through their pores.”
SUMMARY
Sponge is full of holes. These holes are called pores. Porous means full of holes. Sponge is a porous body. All things that are full of holes are porous. Bread,chalk,lump-sugar,and salt are porous bodies.
Lesson 09 The Dog
The boys came home one day full of delight.Teacher had been giving them a lesson on the dog.As they had a faithful old dog of their own,the lesson pleased them very much.
“Shall we bring Ponto in,and have a chat about him？” said Fred. Of course they all said “yes,” and a minute or two later the children were sitting on the loor with Ponto in the middle.
“Now first of all,sister,what does Ponto like best for dinner？” said Fred.
“He likes a piece of meat better than anything,”said Norah.
“Yes,” said Fred,“the dog,like the cat,is a lesheater.
“Open your mouth,Ponto,and let us have a look at your teeth,old boy. Look,Norah,his teeth are sharp and pointed. They are just like the cat’s teeth. They are made for cutting through flesh,not for chewing or grinding. The lower jaw has only one movement—up and down.”
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