Chapter 7_2
材料化学chapter7-2储氢合金
作温度、压力条件要求不高,易于实施,设备简单。 ②氢化物生成热少,具有适于常温使用的氢的平衡分
解压力,而且可根据需要能容易地释放出氢。 ③可供反复使用,历经吸氢释氢的反复循环,其性能
维持不变,不会因为燃料中所含杂质的污染而使吸 氢释氢性能下降。 ④贮氢合金造价低廉、稳定、轻质、便于贮运。
贮氢合金中较使用的合金类型
② 镧镍系合金(LaNi5、La2Mg17、La2Ni5Mg15)
③ 镧镍系合金在常温、低压(1.5x105Pa)下即可
释放氢气,吸氢量大,但含有镧系元素中的稀有金属 镧。相对而言,稀土合金被认为是最好的贮氢合金。 混合稀土类合金是在LaNi5基础上发展起来的一类贮 氢合金。比如MI为富镧的混合稀土价格仅为纯镧的 1/5,性能与LaNi5相当,都易活化。吸氢后体积膨胀 与LaNi5相当。
7.3.2 贮氢合金材料的作用机理
金属贮氢的原理在于这类材料中一个金属原子能与 两个、三个甚至更多的氢原子结合,生成稳定的金属 氢化物,同时放出热量。等将其稍稍加热,氢化物又 会发生分解,将吸收的氢释放出来,同时吸收热量。
有效地利用金属与氢的可逆反应,就可实现化学能 (氢)、热能(反应热)和机械能(平衡氢压)间的 相互转换。
贮氢材料即可作为氢的输送介质,还有一系列其 他用途,如制作稀土贮氢电池、能量转换介质、 分离氢、精制和分离氢的同位素、催化剂和敏感 元件等。
(1)电池材料
镍-氢化物新型二次电池因其比能量高、无污染等优 点已经开始取代传统的镍镉电池在信息产业、航天领域 等大规模应用。贮氢合金作为镍-氢化物电池的负极材 料,既是电池制备的关键材料,也是目前贮氢合金应用 最成熟的领域。
大学物理7-2磁场的源
q
+
r
v
B
q
r
v
B
例4 半径为 R 的带电薄圆盘的电荷面密度为 ,并 以角速度 绕通过盘心垂直于盘面的轴转动,求圆盘 中心的磁感应强度。
解法一 :圆电流的磁场
dq 2 rdr dI rdr T 2 / dB
R o r
0 dI
2r
0
2
dr
7.2
magnetic field and magnetic induction
磁力——电流和磁体之间的相互作用。 (1) 磁铁与磁铁之间的相互作用力 磁铁
同极相斥 异极相吸
注意:如果把一条磁铁折成数段,不论段数 多少或各段的长短如何,每一小段仍将形成 一个很小的磁铁,仍具有N、S两极,即 N 极与 S 极相互依存而不可分离。但是,正电 荷或负电荷却可以独立存在,这是磁现象和 电现象的基本区别。
(1) 将电流分解为无数个电流元 Idl (2) 由电流元求dB (据毕—萨定律)
(3) 将 dB 在坐标系中分解,并用磁场叠加原理做对称 性分析,以简化计算步骤 (4) 对 dB 积分求 B = dB
Bx dBx , B y dB y , Bz dBz
L L L
矢量合成: B B i B j B k x y z
2
x
C
o
0 I B (cos 1 cos 2 ) 4 r
方向:电流与磁感强度成 右手螺旋定则 注意:从直电流始端沿电 流方向积分到末端。 ◆ 无限长载流长直导线 的磁场
z
D
2
B
I
o
x
C
r
(牛津上海版八年级上)Chapter 7《Nobody wins》(Part Ⅱ)Grammar课件(2)
We use some in positive statements about amounts. We use any in negative statements and questions. I have got some questions. She has not got any questions.
Example: S1 Have we got any apples? S2 Yes, we’ve got some apples. S1 Have we got any beans? S2 No, we haven’t got any beans.
1 Workbook 8A, pagy information?
We use some and any before plural countable nouns (e.g., questions) and uncountable nouns (e.g., information).
a) cakes, sandwiches b) orange juice, apple
We use some and any to talk about amounts that are not definite or exact.
Customer: Have you got any tea?
Waiter:
Sorry, we haven’t got any tea, but we’ve got some coffee.
Customer: Have you got any tea? Waiter: Sorry, we haven’t got any tea, but we’ve got some coffee.
juice c) chips, noodles d) milk, soya milk
机械设计基础(第七版)陈云飞 卢玉明主编课后答案
chapter11-1什么是运动副?高副与低副有何区别?答:运动副:使两构件直接接触,并能产生一定相对运动的连接。
平面低副-凡是以面接触的运动副,分为转动副和移动副;平面高副-以点或线相接触的运动副。
1-2什么是机构运动简图?它有什么作用?答:用简单的线条和符号代表构件和运动副,并按比例定出各运动副位置,表示机构的组成和传动情况。
这样绘制出的简明图形就称为机构运动简图。
作用:机构运动简图不仅能表示出机构的传动原理,而且还可以用图解法求出机构上各有关点在所处位置的运动特性(位移,速度和加速度)。
它是一种在分析机构和设计机构时表示机构运动的简便而又科学的方法。
1-3平面机构具有确定运动的条件是什么?答:机构自由度F>0,且与原动件数相等,则机构各构件间的相对运动是确定的;这就是机构具有确定运动的条件。
(复习自由度4个结论P17)chapter22-1什么是曲柄摇杆机构的急回特性和死点位置?答:急回特性:曲柄等速回转的情况下,摇杆往复运动速度快慢不同,摇杆反行程时的平均摆动速度必然大于正行程时的平均摆动速度,此即急回特性。
死点位置:摇杆是主动件,曲柄是从动件,曲柄与连杆共线时,摇杆通过连杆加于曲柄的驱动力F正好通过曲柄的转动中心,所以不能产生使曲柄转动的力矩,机构的这种位置称为死点位置。
即机构的从动件出现卡死或运动不确定的现象的那个位置称为死点位置(从动件的传动角 =0°)。
chapter33-2通常采用什么方法使凸轮与从动件之间保持接触?答:力锁合:利用重力、弹簧力或其他外力使从动件与凸轮轮廓始终保持接触。
形锁合:利用高副元素本身的几何形状使从动件与凸轮轮廓始终保持接触。
3-3什么叫刚性冲击和柔性冲击?用什么方法可以避免刚性冲击?答:刚性冲击:从动件在运动开始和推程终止的瞬间,速度突变为零,理论上加速度为无穷大,产生无穷大的惯性力,机构受到极大的冲击,称为刚性冲击。
柔性冲击:当从动件做等加速或等减速运动时,在某些加速度突变处,其惯性力也随之有限突变而产生冲击,这种由有限突变而引起的冲击比无穷大惯性力引起的刚性冲击轻柔了许多,故被称为柔性冲击。
8B Chapter 7 revision 2
Chapter 7课文回顾We considered the _____question briefly. Pansy said we ____to call it the Mayfield Sun. Millie suggested the Mayfield Mirror __ the Mayfield Star.We all had _____ ideas, and so Joyce said that we should think about this a bit ____. We would make a ____ about the name at the next meeting. We agreed to concluded the meeting then. We arranged to have the next meeting in one ___ time.语法专练1.你应该早起床。
———————————————2.汤姆不应该大声讲话。
———————————————3.我们应该现在回家吗?———————————————1.She ought to speak to me politely.(改为一般疑问句)_____________________________________________2.Y our brother ought to tell you the news.(改为否定句)——————————————————————3.Y ou should be careful when you cross the street.(改为同义句)——————————————————————4.He ought to do it carefully.(改为反义疑问句)——————————————————————5.We ought to arrive there at seven.(对划线部分提问)——————————————————————选择题()1.Tony goes to work by ____train. He usually catches ____7:30 train.A. the, theB. /, aC. the, aD. /, the( ) 2. Do more reading, ____ you will find it easy to write a composition.A. /B. andC. orD.but( ) 3. The teacher said that there ____ planets around the Sun.A. isB. areC. wereD. was( )4. The new edition will add two new sections in order to attract more old people.A. so thatB. as soon asC. so as toD. since( )5. A: The tallest tree in the school garden fell down in the storm last night.B:________!A. That's all rightB. Never mindC. What a pityD. Well done( )6.As they were all sleeping ____of them heard the knock at the door.A. allB. noneC. bothD. any( )7. What ____ you ____ this problem in this strange way?A. make, considerB. make, to considerC. makes, considerD. makes, considering( )8. Wen Hui Daily is famous ____ China.A. forB. inC. toD.in( )9. I wonder ____ was elected the president of the Science Ciub.A. whenB. whoC. howD. where( )10. I hope more museums can be ____ to visitors.A. freeB. busyC. paidD. spent( )11. Feng Xiaogang's films are popular ____young people.A. toB. amongC. betweenD.for( )12. Children ____read all kinds of newspapers.A. needB. need toC. needsD. needs to( )13. After the racing car started, it ran ____.A. quicker and quickerB. more and more quicklyC. quick and quickD. more and more quick ( )14. I can recite ____of passage of Chapter 7.A. two—thirdB. two—thirdsC. second—threeD. second—threes( )15. I often ask for suggestions from my teachers.A. adviceB. reasonsC. hobbiesD. charge( )16. These boys continued discussing how to edit the newspaper ____ it was late.A. butB. as soon asC. afterD. though( )17. Chinese people usually have a thorough cleaning before the Spring Festive.A. ordinaryB. completeC. imcompleteD. common( )18. Mike asked me how long ____.A. I had come to ShanghaiB. had I come to ShanghaiC.I had been in ShanghaiD. I had been to Shanghai( )19. Jack doesn't have lunch at school.____.A. So does PeterB. Peter doesn't, tooC.Neither does PeterD. Neither has Peter( )20. Tom suggested that his best friend ____his father their plan.A. discussB. tellC. discussedD. told用所给词的适当形式填空1. Mr Black told me to answer the question _____.(brief)2. Su Mang is a well—known fashion chief _____.(edit)3. We have a wide _____of the latest products in our city all year around.(choose)4. Who took charge of the meeting which was _____ last Friday?(hold)5. More newspapers are published to meet the needs of different _____.(read)改变句子1. Most students elected Arthur to be the secretary.(对划线部分)_______ ________ most students elect Arthur to be?2. He has been a sports reporter for five years.(改为同义句)He _______ ________ sports reporter five years ago.3. She's got used to reading China Daily, ______ ______?(完成反意疑问句)4. We shouldn't make a noise in public.(改为同义句)We ______ not ______ make a noise in public.5. The Germans published the first modern—style newspaper in 1609.(对划线部分提问)_______ _______ the Germans published the first modern—style newspaper?。
Principles of Accounting CHAP 7-2 Rule-base or Principle-base
Consistency - When a company applies the same
accounting treatment to similar events from period to period.
2. Revenue recognition
3. PMarticnhincgiples
4. Full disclosure
2. Materiality
Third
C3. oInndusstrtyrparaicntictes
level
4. Conservatism
The "how"—
implementation
Financial Reporting
distinctive an2d. aUsnsdepfcuerleicndiitafdsesieccisssiominngseanings. These terms constit3u. tfAuebtuoruett cehansetehrfplloraiwsnes guage of First level
How to develop a coherent set of standards and rules How to solve new and emerging practical problems
Concepts and objectives, basis of the rules
ASSUMPTIONS
Economic Entity
Third Level: Principles
教硕版-Chapter 7-2-方差比率的区间估计与F分布
F分布概率表
附表3是双侧概率表,附表4是单侧概率表,它们都只 给出了两个概率值(用α表示),0.05和0.01. 查F分布表时,根据需要选择双侧表或单侧表,再按 两个自由度及相应的概率去找到对应的 F 值。例:
F0.05(2,9) 4.26
F0.01(2,9) 8.02
其含义是取自同一个正态总体的两个样本n1和n2之方 差的比值F,只有5%的样本可能比4.26大,只有1% 的样本可能比8.06大。
两总体方差之比的区间估计
两总体方差之比的区间估计( F分布) 2 2 2 2 s s 1 1 (df1 n1 1, n1 1 1 n1 1 F 2 ; 2 2 2 s n2 1 2 s n2 1 F 2 df 2 n2 1)
根据F分布,估计两体方差之比的置信区间:
2
(X X )
ns 2
(n 1) s 2 n1
如果从同一个总体中抽样,有 1= 2,则 F
s 2 n1 1 s 2 n2 1
F分布的特点
1、F分布呈正偏态,随着两个自由度的的增大, 趋近于正态分布。 2、当分子的自由度为1,分母的自由度为任意值, F值和分母的自由度相同概率的t值(双侧概率)的 平方相等。
s n1 1 1 2 F / 2 s n2 1
若来自同一总体
例7-8
2
2 1 2 2
F / 2
s s
2 2
n1 1 n2 1
查双侧概率
来自同一总体
F
s 2 n1 1 12 s
2 n2 1
2
; F 2
s 2 n1 1 s
2 n2 1
Chapter 7-2 固相反应(1)
第五节:低温(热)固相反应固相化学反应分为三类, 即反应温度低于100℃的低温固相反应、反应温度介于100~600℃之间的中温固相反应以及反应温度高于600℃的高温固相反应。
低温固相反应的反应物常常是分子固体(如含结晶水的盐)或低维结构化合物。
实例一: 固体4-甲基苯胺与固体CoCl 2·6H 2O 按2∶1 摩尔比在室温(20℃) 下混合, 一旦接触, 界面即刻变蓝, 稍加研磨反应完全, 该反应甚至在0℃同样瞬间变色。
但在CoCl 2的水溶液中加入4-甲基苯胺(同上摩尔比) , 无论是加热煮沸或研磨、搅拌都不能使白色的4-甲基苯胺表面变蓝, 即使在饱和的CoCl 2水溶液中也是如此。
CH 3C 6H 4NH 2, m.p.=44.5℃,b.p.=200.4℃80ºC(1)中和反应。
(2) 氧化还原反应。
(3) 配位反应。
(4) 分解反应。
(5) 离子交换反应。
(6) 成簇反应。
(7) 嵌入反应。
(8) 催化反应。
(9) 取代反应。
(10) 加成反应。
(11) 异构化反应。
(12) 有机重排反应。
(13) 偶联反应。
(14) 缩合或聚合反应。
(15) 主客体包合反应。
(1)潜伏期。
固体反应物间的扩散及产物成核过程便构成了固相反应特有的潜伏期。
这两种过程均受温度的显著影响, 温度越高, 扩散越快, 产物成核越快, 反应的潜伏期就越短; 反之, 则潜伏期就越长。
当低于成核温度Tn时, 固相反应就不能发生。
(2)无化学平衡。
当反应中有气态物质参与时, 如果这些气体组分作为产物的话,随着气体的逸出, 这些气体组分的分压较小, 因而反应一旦开始, 便可一直维持到所有反应物全部消耗, 亦即反应进行到底。
(3) 拓扑化学控制原理。
只有合适取向的晶面上的分子足够地靠近, 才能提供合适的反应中心, 使固相反应得以进行。
(4) 分步反应。
可以通过精确控制反应物的配比等条件, 实现分步反应,得到所需的目标化合物。
《旅游英语视听说》Chapter 7 (2)
3)Being knowledgeable about the checking-out times, hotel services and local attractions is essential. But even more important, are personal warmth, friendliness, and good people skills. 4)When travelers reach their hotel, they are often tired or stressed. The desk clerk’s job is to make them feel truly welcomed and comfortable. So they will make a point of staying at your hotel every time when they are in town. 5)The front desk is an excellent place to start if you are interested in career of hotel management since it allows you to learn about the many different aspects involving in running a hotel efficiently and places you on the front line of customer relations.
following statements are true or false. Write T for true and F for false.
• 1.__F___ Front desk is different from reservation
Chapter 7 课后答案
Chapter 7 答案Discourse Analysis1.Define the following terms briefly.(1)discourse: a general term for examples of language use, i.e. language producedas the result of an act of communication. It refers to the larger units oflanguage such as paragraphs, conversations and interviews.(2)discourse analysis: the study of how sentences in written and spoken languageform larger meaning units such as paragraphs, conversations and interviews.(3)given information: the information that the addresser believes is known to the addressee.(4)new information: the information that the addresser believes is not knownto the addressee.(5)topic: the main center of attention in a sentence.(6)cohesion: the grammatical and/or lexical relationships between the differentelements of a text. This may be the relationship between different sentencesor different parts of a sentence.(7)coherence: the relationship that links the meanings of utterances ina discourseor of the sentences in a text.(8)discourse marker: the technical term for all the items that are used to helpconstruct discourse, such as signifying the beginning or ending of a paragraphor a turn in conversation. They are commonly used in the initial positionof an utterance and are syntactically detachable from a sentence, such aswell, I mean, now, then, first, second, finally.(9)adjacency pair: a set of two consecutive, ordered turns that “go together” in aconversation, such as sequences of question/answer, greeting/greeting, invitation/acceptance, criticism/denial.(10) preference structure: in the conversations there can be several second partsrelated to one first part, but they are not of equal status. The structural likelihoodis called preference, and this likely structure is the preference structurethat divides second parts into preferred and dispreferred. The former is thestructurally expected and the latter unexpected. In answering the question“Have you got a light?”, the reply “Here you are” is preferred and “Sorry, no, I don’t smoke” is dispr eferred.(11 presequence: the opening sequences that are used to set up some special potentialactions, such as greetings before formal conversations. “What are youdoing tonight?” can be used as a presequence if it is followed by “If nothingspecial, come over and have dinner with us please.”(12) critical discourse analysis: the analysis of language use directed at, and committedto, discovering the concealed ideological bias, injustice, inequality in the power relations among speakers and hearers.2.In the study of discourse, cohesion refers to the grammatical and/or lexical relationshipsbetween the different parts of a text. This may be the relationship betweendifferent sentences or different parts of a sentence. It concerns the questionof how sentences are explicitly linked together in a discourse by different kinds ofovert devices. Such cohesive devices include reference, substitution, ellipses, conjunction and lexical cohesion.3.one→the look-out4.them (line 4)→plant and animal species (line 3)that (line 7)→“Every ecosystem everywhere can’t be preserved intact.”it (line 7)→“Every ecosystem everywhere can’t be preserved intact.”it (1st one, line 8)→how can it be made consistent with the earlier objective?it (2nd one, line 8)→to deprive some people in some parts of the world of a pieceof their ecosystem but not others.5.It is not a coherent discourse. Although it has connection words such as a Ford–– a car and black –– Black, which look like cohesive devices, they refer to entirelydifferent things. There is a total lack of internal relation among the sentences. Atext can’t be only based on superficial connections between the words to pursuecoherence; there must be some relationship that links the meanings of the sentencesin a text, too. This text is not in line with our real experience of the way theworld is. Thus, we can’t make sense of it directly unless we are laborious to createmeaningful connections which are not actually expressed by the words and sentences.So it’s not a coheren t discourse.6.Coherence is the relationship that links the meanings of utterances ina discourse or of the sentences in a text. This extract is coherent. All the sentences (questions in fact) are organized around the topic “interview”, and they are arrang ed from the general to the more specific in a logical order so that the text is easy to follow.。
chapter7 (2)
理解集合框架 掌握ArrayList与LinkedList类 掌握HashMap与LinkedHashMap 掌握Iterator类 掌握Collections类和Arrays类
3
使用数组保存所有学员的姓名、年龄、地址信息
◦ 数组无法修改长度,一旦定义了数组,那么它是定长的, 如果新增了一位学员,无疑需要重新定义数组
//此时就可以直接使用String来接收返回值了 String s = it.next(); System.out.println(s); }
12
对于List集合来说,通过listIterator()方法可以获得 一个功能更为强大的列表迭代器ListIterator, ListIterator扩展了Iterator,它过对比ArrayList和LinkedList,不难发现,其实不管 是ArrayList也好,LinkedList也罢,它们的本质区别不 在于几个方法的存在与否,对于ArrayList来说,由于遍 历的便捷,提供了indexOf()方法,对于LinkedList来说, 由于增删的便捷,提供了诸如addFirst()、addLast()、 removeFirst()、removeLast()等方法。
相对与ArrayList来说,基于链表对增加、删除元素 的便捷性,LinkedList提供了addFirst、addLast、 removeFirst、removeLast等方法。
14
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典范英语7-2-吵闹的邻居(1st)
Happiness comes from your heart.
He can communicate with the neighbours, and try to understand and forgive them.
1 Mr Flinch —What is he like?
In a grim, grey house in a grim, grey town lived an unhappy man.(P3) He was a miser (P4)
He was mean and miserable (P4)
What was Mr. Flinch’s problem?
Who are the people on the front cover?
Poppy,
Mr. Flinch, Carl,
possibly a musician.
a mechanic
Read Chapter 1 and answer —Who is Mr. Flinch? —What is he like? —What was his problem?
Do you feel any sympathy for Mr Flinch? Why or why not?
If you were Mr Flinch, what would you do to your noisy neighbours?
What can we learn from the story?
and intonation. Use your voice and expression to tell
CHAPTER 7-2
改变中子泄漏
小型快中子反应堆中, 小型快中子反应堆中,可以用移动反射层的方法改 变中子的泄漏
控制中常用的物理量
过剩反应性ρ 过剩反应性ρex (剩余反应性) 剩余反应性)
堆芯中没有任何控制毒物时的反应性。 堆芯中没有任何控制毒物时的反应性。
控制毒物反应性∆ρ 价值) 控制毒物反应性∆ρi (价值)
棒组的重叠
棒间的干涉效应
调节带和插入极限
调节棒组执行电站负荷调节任务,当堆芯 调节棒组执行电站负荷调节任务, 处于某一功率水平运行时, 处于某一功率水平运行时,调节棒组有一 个正常的活动范围, 个正常的活动范围,这个活动范围称为调 节带。 节带。 在反应堆的寿期初、 末各个阶段, 在反应堆的寿期初、中、末各个阶段,各 调节棒组在零功率至满功率范围内, 调节棒组在零功率至满功率范围内,均有 相应的调节带
某一控制毒物投入堆芯时所引起的反应性变化。 某一控制毒物投入堆芯时所引起的反应性变化。
停堆深度ρ 停堆深度ρs
当全部控制毒物都投入堆芯时, 当全部控制毒物都投入堆芯时,堆所达到的负反 应性。 应性。
总的被控反应性
剩余反应性与停堆深度之和。 剩余反应性与停堆深度之和。 即 ∆ρ=ρex+ρs
各种反应性效应
棒积分价值-IRW(z) 棒积分价值-
棒从某个参考高度移动到该高度时, 棒从某个参考高度移动到该高度时,引入的总的 反应性 参考高度一般选择棒全插或全提位置
棒微分积分价值曲线
控制棒分组
控制棒组分为停堆 棒组和调节棒组两 停堆棒组为A1、 类。停堆棒组为A1、 A2棒组,每组有8 A2棒组 每组有8 棒组, 束控制棒束; 束控制棒束;调节 棒组为T1、T2、T3、 棒组为T1、T2、T3、 T4棒组,包含的控 T4棒组 棒组, 制棒束数分别为8 制棒束数分别为8、 4、4、5 一个控制棒束组件 包括20根控制棒 根控制棒。 包括20根控制棒。
§7-2 沸腾换热与热管
却公式仍然适用,即:
q h(t w t s ) ht
但对于沸腾换热的h却有许多不同的计算公式。
Heat Transfer
建筑工程系
The Department
of Construction Engineering
Logo
1. 大容器饱和核态沸腾 影响核态沸腾的因素主要是过热度和汽化核 心数,而汽化核心数受表面材料、表面状况、压 力等因素的支配,所以沸腾换热的情况液比较复 杂,导致了个计算公式分歧较大。目前存在两种 计算是: ( 1 )针对一种液体的计算公式; ( 2 )广泛适用于各种液体的计算式;
Logo
(2) 汽泡的存在条件 汽泡半径R必须满足下列条件才能存活(克拉贝龙 方程) 2 Ts R Rmin rv (t w t s )
式中: — 表面张力,N/m;r — 汽化潜热,J/kg v — 蒸汽密度,kg/m3;tw — 壁面温度,C
ts — 对应压力下的饱和温度, C
tw ts 。则 其过热度为: ,而贴壁处液体具有最大过热度 tl t s 壁面凹处最先能满足汽泡生成的条件:
讨论:①若表面张力>内外压差,汽泡不能形成。 ②若表面张力<内外压差,界面上汽泡不断蒸发,汽 泡才能成长。
Heat Transfer
建筑工程系
The Department
of Construction Engineering
Heat Transfer
建筑工程系
The Department
of Construction Engineering
Logo
三、沸腾传热机理
D过渡沸腾区 Transition boiling regime 汽泡迅速形成,许多汽泡连成 一片,在壁面上形成一层汽膜,汽 膜的导热系数低。 E,F稳定膜态沸腾区 Stable film boiling regime 汽泡的产生和脱离速度几乎不 变,在壁面上形成稳定的汽膜。 E 区:辐射比例小 F区:辐射所占比例越来越大
Chapter 7-determiners (2)
√
4.A square has four sides. √
5.The telephone was invented in 1876. √
6.A telephone was invented in 1876. X
7.The iphone has become very popular.
√
8.An iphone has become)
When we say the reference is generic, we are talking about any member representative of a class of people or things. All the three forms of article can be used generically to refer to the members of a class as a whole.
Exercises
Textbook: 7A-7F
Home-reading
textbook
page 86-107 Pronouns
Preparation for Quiz 2 in early May Q+A before Quiz 2
Thank you!
X
Specific reference (特指)
Specific reference refers to a particular specimen of the class.Specific reference falls into two kinds:
Indefinite specific reference (非确定特指) Definite specific reference (确定特指)
典范英语7-2读书笔记(优选.)
精品word.最新文件---------------- 仅供参考--------------------已改成-----------word文本 --------------------- 方便更改赠人玫瑰,手留余香。
Name: ________________Class: _________________Submission Date: September / 9 / 2013Title of the book: Coming Clean (7-2)●Translate the following phrases(翻译下列短语;英译汉部分只需译出下划线部分):“怎么回事?”___________________告诉他真相 ___________________就在那时 ___________________盯着某人看 ___________________朝某人笑 ___________________干洗店 ___________________“我们有些事情要告诉您。
”________He looks smart! ____________________turn on the taps _____________________stick his fork into ____________________I am just getting used to it. _______________“Is it working?” Janey asked. _____________We’ll have to own up. ___________________The head promised him a new suit._________1 / 4●Questions and answers:1. Why did Mrs. Venn give a little jump when she saw Mr. Such? (chapter 1)__________________________________________________________________________ ____________________________________________________________________________________________ __________________2. What happened to Mr. Such’s new trousers when Derek and Janey were drawing? (chapter 2)__________________________________________________________________________ ____________________________________________________________________________________________ __________________3. How many ways did they try to get the trousers clean? What are they? (chapter 2-3)__________________________________________________________________________ ____________________________________________________________________________________________ __________________4. When did Derek and Janey deicide to tell Mr Such the truth? (chapter 3)__________________________________________________________________________ ____________________________________________________________________________________________ __________________5. How did Mr. Such smother the flames? What color will be Mr. Such’s new trousers?(chapter 3)__________________________________________________________________________ ____________________________________________________________________________________________ __________________6. What do you think of Mr. Such? (chapter 1-3)__________________________________________________________________________ ____________________________________________________________________________________________ __________________●Brief summary of the each chapter(概括每个章节的简要大意,包括人物、时间、地点、事件等):ChapterOne:___________________________________________________________________________ ___________________________________________________________________________________ ___________________________________________________________________________ ____________________________________ChapterTwo:___________________________________________________________________________ ___________________________________________________________________________________ _____________________________________________________________________________________________ __________________Chapter Three:___________________________________________________________________________ _________________________________________________________________________________ _____________________________________________________________________________________________ __________________最新文件---------------- 仅供参考--------------------已改成-----------word文本 --------------------- 方便更改赠人玫瑰,手留余香。
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Chapter 7The Sounding of the CallWhen Buck earned sixteen hundred dollars in five minutes for JohnThornton, he made it possible for his master to pay off certain debts andto journey with his partners into the East after a fabled lost mine, thehistory of which was as old as the history of the country. Many menhad sought it; few had found it; and more than a few there were who hadnever returned from the quest. This lost mine was steeped in tragedyand shrouded in mystery. No one knew of the first man. The oldesttradition stopped before it got back to him. From the beginning therehad been an ancient and ramshackle cabin. Dying men had sworn to it,and to the mine the site of which it marked, clinching their testimonywith nuggets that were unlike any known grade of gold in the Northland.But no living man had looted this treasure house, and the dead weredead; wherefore John Thornton and Pete and Hans, with Buck and half adozen other dogs, faced into the East on an unknown trail to achievewhere men and dogs as good as themselves had failed. They sleddedseventy miles up the Yukon, swung to the left into the Stewart River,passed the Mayo and the McQuestion, and held on until the Stewartitself became a streamlet, threading the upstanding peaks which markedthe backbone of the continent.John Thornton asked little of man or nature. He was unafraid of thewild. With a handful of salt and a rifle he could plunge into thewilderness and fare wherever he pleased and as long as he pleased.Being in no haste, Indian fashion, he hunted his dinner in the course ofthe day's travel; and if he failed to find it, likethe Indian, he kept ontravelling, secure in the knowledge that sooner or later he would come toit. So, on this great journey into the East, straight meat was the bill offare, ammunition and tools principally made up the load on the sled, andthe time-card was drawn upon the limitless future.To Buck it was boundless delight, this hunting, fishing, andindefinite wandering through strange places. For weeks at a time theywould hold on steadily, day after day; and for weeks upon end theywould camp, here and there, the dogs loafing and the men burning holesthrough frozen muck and gravel and washing countless pans of dirt bythe heat of the fire. Sometimes they went hungry, sometimes theyfeasted riotously, all according to the abundance of game and the fortuneof hunting. Summer arrived, and dogs and men packed on their backs,rafted across blue mountain lakes, and descended or ascended unknownrivers inslender boats whipsawed from the standing forest.The months came and went, and back and forth they twisted throughthe uncharted vastness, where no men were and yet where men had beenif the Lost Cabin were true. They went across divides in summerblizzards, shivered under the midnight sun on naked mountains betweenthe timber line and the eternal snows, dropped into summer valleys amidswarming gnats and flies, and in the shadows of glaciers pickedstrawberries and flowers as ripe and fair as any the Southland couldboast. In the fall of the year they penetrated a weird lake country, sadand silent, where wild- fowl had been, but where then there was no life norsign of life-- only the blowing of chill winds, the forming of ice insheltered places, and the melancholy rippling of waves on lonely beaches.And through another winter they wandered on the obliteratedtrailsof men who had gone before. Once, they came upon a path blazedthrough the forest, an ancient path, and the Lost Cabin seemed very near.But the path began nowhere and ended nowhere, and it remainedmystery, as the man who made it and the reason he made it remainedmystery. Another time they chanced upon thetime-graven wreckage ofa hunting lodge, and amid the shreds of rotted blankets John Thorntonfound a long-barrelled flint-lock. He knew it for a Hudson BayCompany gun of the young days in the Northwest, when such a gun wasworth its height in beaver skins packed flat, And that was all--no hint asto the man who in an early day had reared the lodge and left the gunamong the blankets.Spring came on once more, and at the end of all their wandering theyfound, not the Lost Cabin, but a shallow placerin a broad valley wherethe gold showed like yellow butter across the bottom of the washing-pan.They sought no farther. Each day they worked earned them thousandsof dollars in clean dust and nuggets, and they worked every day. Thegold was sacked in moose-hide bags, fifty pounds to the bag, and piledlike so much firewood outside the spruce-bough lodge. Like giantsthey toiled, days flashing on the heels of days like dreams as theyheaped the treasure up.There was nothing for the dogs to do, save the hauling in of meatnow and again that Thornton killed, and Buck spent long hours musingby the fire. The vision of the short-legged hairy man came to him morefrequently, now that there was little work to be done; and often, blinkingby the fire, Buck wandered with him in that other world which he remembered.The salient thing of this other world seemed fear. Whenhewatched the hairy man sleeping by the fire, head between his knees andhands clasped above, Buck saw that he slept restlessly, with many startsand awakenings, at which times he would peer fearfully into thedarkness and fling more wood upon the fire. Did they walk by thebeach of a sea, where the hairy man gathered shell- fish and ate them as hegathered, it was with eyes that roved everywhere for hidden danger andwith legs prepared to run like the wind at its first appearance. Throughthe forest they crept noiselessly, Buck at the hairy man's heels; and theywere alert and vigilant, the pair of them, ears twitching and moving andnostrils quivering, for the man heard and smelled as keenly as Buck.The hairy man could spring up into the trees and travel ahead as fast ason the ground, swinging by the arms from limb to limb, sometimes adozen feet apart, letting go and catching,never falling, never missing hisgrip. In fact, he seemed as much at home among the trees as on theground; and Buck had memories of nights of vigil spent beneath treeswherein the hairy man roosted, holding on tightly as he slept.And closely akin to the visions of the hairy man was the call stillsounding in the depths of the forest. It filled him with a great unrestand strange desires. It caused him to feel a vague, sweet gladness, andhe was aware of wild yearnings and stirrings for he knew not what.Sometimes he pursued the call into the forest, looking for it as though itwere a tangible thing, barking softly or defiantly, as the mood mightdictate. He would thrust his nose into the cool wood moss, or into theblack soil where long grasses grew, and snort with joy at the fat earthsmells; or he would crouch for hours, as if in concealment, behindfungus-covered trunks of fallen trees, wide-eyed and wide-eared to allthat moved and sounded about him. It might be, lying thus, that hehoped to surprise this call he could not understand. But he did notknow why he did these various things. He was impelled to do them,and did not reason about them at all.Irresistible impulses seized him. He would be lying in camp,dozing lazily in the heat of the day, when suddenly his head would liftand his ears cock up, intent and listening, and he would spring to his feetand dash away, and on and on, for hours, through the forest aisles andacross the open spaces where the niggerheads bunched. He loved torun down dry watercourses, and to creep and spy upon the bird life in thewoods. For a day at a time he would lie in the underbrush where hecould watch the partridges drumming and strutting up and down. Butespecially he loved to run in the dim twilight ofthe summer midnights,listening to the subdued and sleepy murmurs of the forest, reading signsand sounds as man may read a book, and seeking for the mysterioussomething thatcalled--called, waking or sleeping, at all times, for him to come.One night he sprang from sleep with a start, eager-eyed, nostrilsquivering and scenting, his mane bristling in recurrent waves. From theforest came the call (or one note of it, for the call was many noted),distinct and definite as never before,--a long-drawn howl, like, yet unlike,any noise made by husky dog. And he knew it, in the old familiar way,as a sound heard before. He sprang through the sleeping camp and inswift silence dashed through the woods. As he drew closer to the cryhe went more slowly, with caution in every movement, till he came to anopen place among the trees, and looking out saw, erect onhaunches,with nose pointed to the sky, a long, lean, timber wolf.He had made no noise, yet it ceased from its howling and tried tosense his presence. Buck stalked into the open, half crouching, bodygathered compactly together, tail straight and stiff, feet falling withunwonted care. Every movement advertised commingled threateningand overture of friendliness. It was the menacing truce that marks themeeting of wild beasts that prey. But the wolf fled at sight of him.He followed, with wild leapings, in a frenzy to overtake. He ran himinto a blind channel, in the bed of the creek where a timber jam barredthe way. The wolf whirled about, pivoting on his hind legs after thefashion of Joe and of all cornered husky dogs, snarling and bristling,clipping his teeth together in a continuous and rapid succession of snaps.Buck did not attack, but circled him about and hedged himin withfriendly advances. The wolf was suspicious and afraid; for Buck madethree of him in weight, while his head barely reached Buck's shoulder.Watching his chance, he darted away, and the chase was resumed.Time and again he was cornered, and the thing repeated, though he wasin poor condition, or Buck could not so easily have overtaken him. Hewould run till Buck's head was even with his flank, when he would whirlaround at bay, only to dash away again at the first opportunity.But in the end Buck's pertinacity was rewarded; for the wolf, findingthat no harm was intended, finally sniffed noses with him. Then theybecame friendly, and played about in the nervous, half- coy way withwhich fierce beasts belie their fierceness. After some time of this thewolf started off at an easy lope ina manner that plainly showed he wasgoing somewhere. He made it clear to Buck that he was to come, andthey ran side by side through the sombre twilight, straight up the creekbed, into the gorge from which it issued, and across the bleak dividewhere it took its rise.On the opposite slope of the watershed they came down into a levelcountry where were great stretches of forest and many streams, andthrough these great stretches they ran steadily, hour after hour, the sunrising higher and the day growing warmer. Buck was wildly glad. Heknew he was at last answering the call, running by the side of his woodbrother toward the place from where the call surely came. Oldmemories were coming upon him fast, and he was stirring to them as ofold he stirred to the realities of which they were the shadows. He haddone this thing before, somewhere in that other and dimly rememberedworld, andhe was doing it again, now, running free in the open, theunpacked earth underfoot, the wide sky overhead.They stopped by a running stream to drink, and, stopping, Buckremembered John Thornton. He sat down. The wolf started ontoward the place from where the call surely came, then returned to him,sniffing noses and making actions as though to encourage him. ButBuck turned about and started slowly on the back track. For the betterpart of an hour the wild brother ran by his side, whining softly. Thenhe sat down, pointed his nose upward, and howled. It was a mournfulhowl, and as Buck held steadily on his way he heard it grow faint andfainter until it was lost in the distance.John Thornton was eating dinner when Buck dashed into camp andsprang upon him in a frenzy of affection, overturning him, scramblingupon him, licking his face, biting hishand--"playing the general tom-fool," as John Thornton characterized it, the while he shook Buck backand forth and cursed him lovingly.For two days and nights Buck never left camp, never let Thorntonout of his sight. He followed him about at his work, watched himwhile he ate, saw him into his blankets at night and out of them in themorning. But after two days the call in the forest began to sound moreimperiously than ever. Buck's restlessness came back on him, and hewas haunted by recollections of the wild brother, and of the smiling landbeyond the divide and the run side by side through the wide foreststretches. Once again he took to wandering in the woods, but the wildbrother came no more; and though he listened through long vigils, themournful howl was never raised.He began to sleep out at night, staying away from camp fordays at atime; and once he crossed the divide at the head of the creek and wentdown into the land of timber and streams. There he wandered for aweek, seeking vainly for fresh sign of the wild brother, killing his meatas he travelled and travelling with the long, easy lope that seems neverto tire. He fished for salmon in a broad stream that emptied somewhereinto the sea, and by this stream he killed a large black bear, blinded bythe mosquitoes while likewise fishing, and raging through the foresthelpless and terrible. Even so, it was a hard fight, and it aroused thelast latent remnants of Buck's ferocity. And two days later, when hereturned to his kill and found a dozen wolverenes quarrelling over thespoil, he scattered them like chaff; and those that fled left two behindwho would quarrel no more.The blood-longing became stronger than ever before. He wasakiller, a thing that preyed, living on the things that lived, unaided, alone,by virtue of his own strength and prowess, surviving triumphantly in ahostile environment where only the strong survived. Because of all thishe became possessed of a great pride in himself, which communicateditself like a contagion to his physical being. It advertised itself in allhis movements, was apparent in the play of every muscle, spoke plainlyas speech in the way he carried himself, and made his glorious furry coatif anything more glorious. But for the stray brown on his muzzle andabove his eyes, and for the splash of white hair that ran midmost downhis chest, he might well have been mistaken for a gigantic wolf, largerthan the largest of the breed. From his St. Bernard father he hadinherited size and weight, but it was his shepherd mother who had givenshape to that size and weight. His muzzle was the long wolf muzzle,savethat was larger than the muzzle of any wolf; and hishead,somewhat broader, was the wolf head on a massive scale. His cunningwas wolf cunning, and wild cunning; his intelligence, shepherdintelligence and St. Bernard intelligence; and all this, plus anexperience gained in the fiercest of schools, made him as formidable acreature as any that intelligence roamed the wild. A carnivorous animalliving on a straight meat diet, he was in full flower, at the high tide of hislife, overspilling with vigor and virility. When Thornton passed acaressing hand along his back, a snapping and crackling followed thehand, each hair discharing its pent magnetism at the contact. Everypart, brain and body, nerve tissue and fibre, was keyed to the mostexquisite pitch; and between all the parts there was a perfect equilibriumor adjustment. To sights and sounds and events which requiredaction, he responded with lightning-likerapidity. Quickly as a huskydog could leap to defend from attack or to attack, he could leap twice asquickly. He saw the movement, or heard sound, and responded in lesstime than another dog required to compass the mere seeing or hearing.He perceived and determined and responded in the same instant. Inpoint of fact the three actions of perceiving, determining, and respondingwere sequential; but so infinitesimal were the intervals of time betweenthem that they appeared simultaneous. His muscles were surchargedwith vitality, and snapped into play sharply, like steel springs. Lifestreamed through him in splendid flood, glad and rampant, until itseemed that it would burst him asunder in sheer ecstasy and pour forthgenerously over the world."Never was there such a dog," said John Thornton one day, as thepartners watched Buck marching out of camp."When he was made, the mould was broke," said Pete."Py jingo! I t'ink so mineself," Hans affirmed.They saw him marching out of camp, but they did not see the instantand terrible transformation which took place as soon as he was withinthe secrecy of the forest. He no longer marched. At once he became athing of the wild, stealing along softly, cat- footed, a passing shadow thatappeared and disappeared among the shadows. He knew how to takeadvantage of every cover, to crawl on his belly like a snake, and like asnake to leap and strike. He could take a ptarmigan from its nest, kill arabbit as it slept, and snap in mid air the little chipmunks fleeing asecond too late for the trees. Fish, in open pools, were not too quickfor him; nor were beaver, mending their dams, too wary. He killed toeat, not from wantonness; but he preferred to eat what he killed himself.So a lurking humor ran through his deeds, and it was his delight to stealupon the squirrels, and, when he all but had them, to let them go,chattering in mortal fear to the treetops.As the fall of the year came on, the moose appeared in greaterabundance, moving slowly down to meet the winter in the lower and lessrigorous valleys. Buck had already dragged down a stray part-growncalf; but he wished strongly for larger and more formidable quarry, andhe came upon it one day on the divide at the head of the creek. A bandof twenty moose had crossed over from the land of streams and timber,and chief among them was a great bull. He was in a savage temper,and, standing over six feet from the ground, was as formidable anantagonist as even Buck could desire. Back and forth the bull tossed hisgreat palmated antlers, branching to fourteen points and embracingseven feet within the tips. His small eyes burned witha vicious andbitter light, while he roared with fury at sight of Buck.From the bull's side, just forward of the flank, protruded a featheredarrow-end, which accounted for his savageness. Guided by that instinctwhich came from the old hunting days of the primordial world, Buckproceeded to cut the bull out from the herd. It was no slight task. Hewould bark and dance about in front of the bull, just out of reach of thegreat antlers and of the terrible splay hoofs which could have stampedhis life out with a single blow. Unable to turn his back on the fangeddanger and go on, the bull would be driven into paroxysms of rage. Atsuch moments he charged Buck, who retreated craftily, luring him on bya simulated inability to escape. But when he was thus separated fromhis fellows, two or three of the younger bulls would charge back uponBuck and enable the wounded bullto rejoin the herd.There is a patience of the wild--dogged, tireless, persistent as lifeitself--that holds motionless for endless hours the spider in its web, thesnake in its coils, the panther in its ambuscade; this patience belongspeculiarly to life when it hunts its living food; and it belonged to Buckas he clung to the flank of the herd, retarding its march, irritating theyoung bulls, worrying the cows with their half-grown calves, anddriving the wounded bull mad with helpless rage. For half a day thiscontinued. Buck multiplied himself, attacking from all sides,enveloping the herd in a whirlwind of menace, cutting out his victim asfast as it could rejoin its mates, wearing out the patience of creaturespreyed upon, which is a lesser patience than that of creatures preying.As the day wore along and the sun dropped to its bed inthenorthwest (the darkness had come back and the fall nights were sixhours long), the young bulls retraced their steps more and morereluctantly to the aid of their beset leader. The down-coming winter washarrying them on to the lower levels, and it seemed they could nevershake off this tireless creature that held them back. Besides, it was notthe life of the herd, or of the young bulls, that was threatened. The lifeof only one member was demanded, which was a remoter interest thantheir lives, and in the end they were content to pay the toll.As twilight fell the old bull stood with lowered head, watching hismates--the cows he had known, the calves he had fathered, the bulls hehad mastered--as they shambled on at a rapid pace through the fadinglight. He could not follow, for before his nose leaped the mercilessfanged terror that would not let him go. Three hundredweight morethan half a ton heweighed; he had lived a long, strong life, full of fightand struggle, and at the end he faced death at the teeth of a creaturewhose head did not reach beyond his great knuckled knees.From then on, night and day, Buck never left his prey, never gave it amoment's rest, never permitted it to browse the leaves of trees or theshoots of young birch and willow. Nor did he give the wounded bullopportunity to slake his burning thirst in the slender trickling streamsthey crossed. Often, in desperation, he burst into long stretches of flight.At such times Buck did not attempt to stay him, but loped easily at hisheels, satisfied with the way the game was played, lying down when themoose stood still, attacking him fiercely when he strove to eat or drink.The great head drooped more and more under its tree of horns,andthe shambling trot grew weak and weaker. He took to standing for longperiods, with nose to the ground and dejected ears dropped limply; andBuck found more time in which to get water for himself and in which torest. At such moments, panting with red lolling tongue and with eyesfixed upon the big bull, it appeared to Buck that a change was comingover the face of things. He could feel a new stir in the land. As themoose were coming into the land, other kinds of life were coming in.Forest and stream and air seemed palpitant with their presence. Thenews of it was borne in upon him, not by sight, or sound, or smell, butby some other and subtler sense. He heard nothing, saw nothing, yetknew that the land was somehow different; that through it strange thingswere afoot and ranging; and he resolved to investigate after he hadfinished the business in hand.At last, at the end of the fourth day, he pulled the great moose down.For a day and a night he remained by the kill, eating and sleeping, turnand turn about. Then, rested, refreshed and strong, he turned his facetoward camp and John Thornton. He broke into the long easy lope, andwent on, hour after hour, never at loss for the tangled way, headingstraight home through strange country with a certitude of direction thatput man and his magnetic needle to shame.As he held on he became more and more conscious of the new stir inthe land. There was life abroad in it different from the life which hadbeen there throughout the summer. No longer was this fact borne inupon him in some subtle, mysterious way. The birds talked of it, thesquirrels chattered about it, the very breeze whispered of it. Severaltimes he stopped and drew in thefresh morning air in great sniffs,reading a message which made him leap on with greater speed. He wasoppressed with a sense of calamity happening, if it were not calamityalready happened; and as he crossed the last watershed and droppeddown into the valley toward camp, he proceeded with greater caution.Three miles away he came upon a fresh trail that sent his neck hairrippling and bristling, It led straight toward camp and John Thornton.Buck hurried on, swiftly and stealthily, every nerve straining and tense,alert to the multitudinous details which told a story--all but the end.His nose gave him a varying description of the passage of the life on theheels of which he was travelling. He remarked die pregnant silence ofthe forest. The bird life had flitted. The squirrels were in hiding.One only he saw,--a sleek gray fellow, flattened against a gray dead limbso that he seemed a part of it, a woody excrescence upon the wood itself.As Buck slid along with the obscureness of a gliding shadow, hisnose was jerked suddenly to the side as though a positive force hadgripped and pulled it. He followed the new scent into a thicket andfound Nig. He was lying on his side, dead where he had draggedhimself, an arrow protruding, head and feathers, from either side of his body.A hundred yards farther on, Buck came upon one of the sled-dogsThornton had bought in Dawson. This dog was thrashing about in adeath-struggle, directly on the trail, and Buck passed around him withoutstopping. From the camp came the faint sound of many voices, risingand falling in a sing-song chant. Bellying forward to the edge of theclearing, he found Hans,lying on his face, feathered with arrows like aporcupine. At the same instant Buck peered out where the spruce-bough lodge had been and saw what made his hair leap straight up on hisneck and shoulders. A gust of overpowering rage swept over him. Hedid not know that he growled, but he growled aloud with a terribleferocity. For the last time in his life he allowed passion to usurpcunning and reason, and it was because of his great love for JohnThornton that he lost his head. The Yeehats were dancing about thewreckage of the spruce-bough lodge when they heard a fearful roaringand saw rushing upon them an animal the like of which they had neverseen before. It was Buck, a live hurricane of fury, hurling himself uponthem in a frenzy to destroy. He sprang at the foremost man (it was thechief of the Yeehats), ripping the throat wide open till the rent jugularspouted a fountain of blood. He did not pause to worrythe victim, butripped in passing, with the next bound tearing wide the throat of asecond man. There was no withstanding him. He plunged about intheir very midst, tearing, rending, destroying, in constant and terrificmotion which defied the arrows they discharged at him. In fact, soinconceivably rapid were his movements, and so closely were theIndians tangled together, that they shot one another with the arrows; andone young hunter, hurling a spear at Buck in mid air, drove it throughthe chest of another hunter with such force that the point broke throughthe skin of the back and stood out beyond. Then a panic seized theYeehats, and they fled in terror to the woods, proclaiming as they fledthe advent of the Evil Spirit.And truly Buck was the Fiend incarnate, raging at their heels anddragging them down like deer as they raced through the trees. It was afateful day for the Yeehats. They scattered farand wide over theThe Call of the Wild country, and it was not till a week later that the last of the survivorsgathered together in a lower valley and counted their losses. As forBuck, wearying of the pursuit, he returned to the desolated camp. Hefound Pete where he had been killed in his blankets in the first momentof surprise. Thornton's desperate struggle was fresh-written on theearth, and Buck scented every detail of it down to the edge of a deeppool. By the edge, head and fore feet in the water, lay Skeet, faithful tothe last. The pool itself, muddy and discolored from the sluice boxes,effectually hid what it contained, and it contained John Thornton; forBuck followed his trace into the water, from which no trace led away.。