詹姆斯·克拉克·麦克斯韦James Clerk Maxwell

詹姆斯·克拉克·麦克斯韦出生于爱丁堡印度街14号，这是一栋他父母在19世纪20年代建造的房子。

你可以在探访詹姆斯·克拉克·麦克斯韦故居上看到更多关于这座房子的信息。

不久之后，他家搬到了柯库布里郡格伦莱尔的家，那里距离邓弗里斯约20公里。他在那里享受了乡村的成长环境，他的天生好奇心在幼年就显露出来。在1834年4月25日写的一封信中，当“这个男孩”还不到三岁时，他被描述如下，见[3]：-

他是个非常快乐的孩子，自从天气变得温和以来进步很大；他对门、锁、钥匙等东西很感兴趣，“给我看看它是怎么做的”这句话从不离口。他还探究溪流和门铃线的隐蔽走向，水如何从池塘穿过墙壁、通过一个拱道或小桥，再沿着排水沟流下……

麦克斯韦八岁时母亲去世。他父母计划让他在家接受教育直到13岁，然后他就能去爱丁堡大学，但这个计划落空了。他们雇了一个16岁的男孩做家庭教师，但这一安排并不成功，于是决定让麦克斯韦去爱丁堡公学。

麦克斯韦与家人于1841年11月18日抵达赫里奥特街31号，即他父亲的姐妹伊莎贝拉约瑟夫·韦德伯恩的家。他进入爱丁堡学院就读，在那里得到了“傻瓜”的绰号。彼得·格思里·泰特虽然年龄几乎相同，却比麦克斯韦低一个年级。彼得·格思里·泰特后来成为他亲密的校友和终身朋友，他这样描述麦克斯韦的学校时光[42]：-

在学校里，他起初被认为害羞且相当迟钝。他没有结交朋友，偶尔的假期都用来阅读古老的歌谣、绘制奇特的图表和制作粗糙的机械模型。这种专注投入，对他的同学们来说完全无法理解，因为他们当时对数学一无所知，这为他赢得了一个不太光彩的绰号。然而，大约在学业中期，他突然成为同学中最杰出的人之一，令同伴们大为惊讶，在奖学金、数学和英语诗歌方面屡获奖项，有时甚至获得最高奖。

1846年初，14岁的麦克斯韦写了一篇关于卵形线的论文。在这项工作中，他推广了椭圆的定义，通过定义一点的轨迹，其中$m$乘以到一个固定点的距离加上$n$乘以到第二个固定点的距离之和为常数。如果$m = n = 1$，则该曲线为椭圆。麦克斯韦还定义了具有两个以上焦点的曲线。这成为他的第一篇论文On the description of oval curves, and those having a plurality of foci，于1846年4月6日在爱丁堡皇家学会上宣读。这些想法并非完全新颖，因为勒内·笛卡儿此前已定义过此类曲线，但这项工作对于一个14岁的孩子来说非常出色。

麦克斯韦不是爱丁堡学院的dux，这个荣誉归于刘易斯·坎贝尔，他后来成为圣安德鲁斯大学的希腊语教授。刘易斯·坎贝尔是麦克斯韦的亲密朋友，他写了传记[3]及其第二版[4]。这些传记充满了个人回忆，读起来引人入胜。

1847年11月，16岁的麦克斯韦进入菲利普·凯兰教授的第二数学班、福布斯教授的自然哲学（物理）班以及威廉·哈密顿从男爵教授的邏輯班。彼得·格思里·泰特同样在爱丁堡大学，后来在Proceedings of the Royal Society of Edinburgh（1879-80）中写道[6]：-

1847年冬天，我们一同出现在福布斯和菲利普·凯兰的课堂上，他在那里表现极为突出。在前者的课上，他特别受宠，获准自由使用课堂设备进行原创实验。……在此期间，他写了两篇有价值的论文，发表在我们的《学报》上，分别是《滚动曲线理论》和《弹性固体的平衡》。

爱丁堡大学至今仍保存着麦克斯韦在本科期间借回家阅读的书籍记录。这些包括

奥古斯丁·路易·柯西，Calcul Différentiel
约瑟夫·傅里叶，Théorie de la Chaleur
加斯帕尔·蒙日，Géometrie Descriptive
艾萨克·牛顿，Optics
西莫恩·德尼·泊松，Mechanics
布鲁克·泰勒，Scientific Memoirs
Willis，Principles of Mechanism

麦克斯韦于1850年10月进入剑桥大学彼得学院，但后来转到三一学院，因为他认为在那里更容易获得奖学金。我们再次引用彼得·格思里·泰特在Proceedings of the Royal Society of Edinburgh（1879-80）中的文章：-

……他在1850年秋天来到剑桥时，已经掌握了大量知识，对于一个如此年轻的人来说，这确实非常惊人，但其杂乱无章的状态令他那有条不紊的私人导师感到震惊。尽管导师是威廉·霍普金斯，但学生在很大程度上自行其是，可以毫不夸张地说，近年来没有哪位高水平的数学荣誉学位考试一等及格者（Wrangler）在进入参议院时，比麦克斯韦更缺乏训练以产出“有回报的”工作。但凭借纯粹的智力，尽管在考试条件下如何有效运用知识方面所知甚少，他还是获得了第二名优等生（Second Wrangler）的位置，并在史密斯奖（Smith's Prizes）这一更高难度的考验中与第一名优等生（Senior Wrangler）并列。

Thomson [42]描述了麦克斯韦的本科时代：-

……学者们在一张桌子上共同用餐。这使麦克斯韦每天都能接触到学院中最具才智的一群人，其中许多人在后来的生活中取得了卓越成就。尽管他害羞且有些古怪，这些人还是认可了他非凡的能力。……麦克斯韦给所有遇到他的人留下的力量印象是显著的；这往往更多归因于他的个性而非他所说的话，因为许多人发现很难跟上他快速从一个话题切换到另一个话题，他活跃的想象力同时启动了许多线索，以至于在追完一个之前就已经转向了另一个。

麦克斯韦于1854年获得了奖学金，并从三一学院毕业，获得数学学位。那一年的第一名优等生是爱德华·约翰·劳思，他不仅是一位优秀的数学家，还是一位精通当时剑桥荣誉学位考试（Tripos）所需应试方法的天才。麦克斯韦留在剑桥招收学生，随后由三一学院授予奖学金以继续工作。

麦克斯韦最重要的成就之一是他对麦可·法拉第的电力和磁力线理论的扩展和数学表述。他的论文On Faraday's lines of force于1855年和1856年分两部分在剑桥哲学学会上宣读。麦克斯韦表明，几个相对简单的数学方程可以表达电场和磁场的行为及其相互关系。

然而，在1856年初，麦克斯韦的父亲生病了，麦克斯韦希望能有更多时间陪伴他。因此，他试图在苏格兰获得一个职位，当Forbes告诉他阿伯丁的马里沙尔学院自然哲学教授职位空缺时，他申请了该职位。麦克斯韦于1856年复活节假期前往爱丁堡与父亲团聚，两人一起去了Glenlair。4月3日，他的父亲去世，不久之后，麦克斯韦按计划返回了剑桥。在4月底之前，他得知自己已被任命为马里沙尔学院的讲席教授。

1856年11月，麦克斯韦在阿伯丁接受了任命。当剑桥大学圣弗瑞兹·约翰学院宣布1857年约翰·柯西·亚当斯奖的题目为The Motion of Saturn's Rings时，麦克斯韦立即产生了兴趣。麦克斯韦和彼得·格思里·泰特在1847年还是爱丁堡学院的学生时就思考过土星环的问题。麦克斯韦决定角逐该奖，他在阿伯丁头两年的研究就围绕这个课题展开。他证明，只有当环由大量微小固体颗粒组成时才能实现稳定，这一解释现已被旅行者号航天器证实。1857年8月28日，麦克斯韦在格伦莱尔时写给刘易斯·坎贝尔的信中写道：-

我已在固体环上造成了几个缺口，现在正一头扎进流体环中，伴随着一场真正令人震惊的符号碰撞。等我重新出现时，将会是在暗环中，那有点像从一片炮林中发起的塞瓦斯托波尔围城战，炮林一个方向延伸100英里，另一个方向延伸30,000英里，炮弹永不停歇，而是绕着一个半径170,000英里的圆圈旋转飞去……

麦克斯韦的论文为他赢得了约翰·柯西·亚当斯奖，乔治·比德尔·艾里写道：-

这是我所见过的最非凡的数学应用于物理学的例子之一。

1858年2月，麦克斯韦与凯瑟琳·玛丽·杜瓦订婚，并于1859年6月结婚。尽管他此时已娶了马歇尔学院院长的女儿，但在1860年马歇尔学院与国王学院合并时，麦克斯韦作为系里资历较浅者，不得不另谋职位。然而，他的科学工作一直进展得非常成功。乔治·加布里埃尔·斯托克斯曾在1857年11月7日写信给他：-

我刚收到你关于动力学陀螺等的论文，以及关于颜色感知实验的报告。后者在发表时我错过了，刚刚怀着极大的兴趣读完。这些结果为三原色感知理论提供了最非凡、最重要的证据，据我所知，这一理论是你，而且只有你，建立在精确的数值基础之上。

1859年，爱丁堡大学自然哲学讲席空缺，福布斯已转赴圣安德鲁斯，命运似乎对麦克斯韦微笑，要将他带回故乡。他在1859年11月30日写信请麦可·法拉第为他作推荐人。麦克斯韦的许多朋友也申请了这一职位，包括彼得·格思里·泰特和爱德华·约翰·劳思。尽管麦克斯韦科学成就卓著，却败给了彼得·格思里·泰特。爱丁堡报纸Courant报道这一结果时指出：

麦克斯韦已被公认为科学界所知最杰出的人物之一。

他未被任命的原因，必定就是该报所写的：

……在我们这样的大学里，教授还应具备另一种品质，那就是在假定学生知识不完善、甚至完全无知的前提下进行口头讲解的能力。

说他不是教资质不佳学生的最佳人选，这或许不无道理，但他讲课差则肯定不是事实。乔治·加布里埃尔·斯托克斯在1854年写道，他：

……曾有一次在场，当时[麦克斯韦]向剑桥哲学学会报告他的几何研究，那次我对他异常清晰的阐述方式印象深刻。

再次，威廉敏娜·弗莱明曾听过麦克斯韦的讲座，表达了类似的想法[22]：-

简而言之，麦克斯韦学识过于渊博，独创性过强，难以在基础教学中发挥最佳水平。然而，对于那些能跟上他的人来说，他的教学是一种享受。

1860年，麦克斯韦被任命为伦敦国王学院自然哲学讲席的 vacant 职位。麦克斯韦在这个职位上度过的六年是他进行最重要实验工作的时期。这个职位的职责比阿伯丁的更为繁重。坎贝尔在[3]中写道：-

一年中有九个月的授课，晚上为工匠等开设的讲座也被视为教授职责的一部分。

在伦敦，大约1862年，麦克斯韦计算出电磁场的传播速度大约等于光速。他因此提出光现象是一种电磁现象。麦克斯韦写下了真正非凡的话：-

我们几乎无法避免这样的结论：光是由同一种介质的横向波动构成的，而这种介质是电和磁现象的原因。

麦克斯韦还继续了他在阿伯丁开始的工作，研究气体动理论。1866年，他通过对气体进行统计处理，独立于Ludwig 路德维希·玻尔兹曼，提出了麦克斯韦-路德维希·玻尔兹曼气体动理论。这一理论表明，温度和热量只涉及分子运动。

这一理论意味着从确定性概念——热量被视为从热流向冷——转变为统计概念：高温分子只有高概率向低温分子运动。麦克斯韦的方法并未拒绝早期的热力学研究，而是使用更好的基础理论来解释观察和实验。

麦克斯韦于1865年春天离开伦敦国王学院，回到他在苏格兰的庄园格伦莱尔。他定期前往剑桥，并于1871年颇为勉强地接受了剑桥的聘请，成为首位卡文迪什物理学讲席教授。他设计了卡文迪什实验室并协助建立。该实验室于1874年6月16日正式启用。

这四个偏微分方程，即今所称的麦克斯韦方程组，首次以完整发展的形式出现在Electricity and Magnetism（1873年）中。这项工作的大部分是麦克斯韦在格伦莱尔、于其担任伦敦职位之后与就任卡文迪什讲席之前的那段时期完成的。它们是19世纪数学的伟大成就之一。

1874年至1879年间，占据麦克斯韦大部分时间的一项任务，是他编辑Henry Cavendish论文的工作。Cavendish，见[14]：-

……只发表了两篇论文[并]留下了二十包关于数学电学和实验电学的手稿。……麦克斯韦以极大的热情投入这项工作：他让自己的头脑充分吸收Cavendish时期的科学文献；他重复了Cavendish的许多实验，并亲手抄写了手稿。……题为‘The Electrical Researches of the Honourable Henry Cavendish’的卷册于1879年出版，作为电学史中的一章，无与伦比。

弗莱明听了麦克斯韦在剑桥的最后一门课程。他写道[22]：-

在1879年5月的最后一个学期，麦克斯韦的健康显然开始衰退，但他仍继续讲课直到学期结束。……哪怕只是短暂地亲身结识麦克斯韦教授，并享有聆听他口头讲授的殊荣，这本身就是一种自由教育，不仅如此，它还是一种启迪，因为他所说的或所做的每一件事，都带有天才的明确印记，这不仅令人极为钦佩，也令人极为敬仰。

麦克斯韦和同样生病的妻子回到Glenlair度夏。他的健康继续恶化，尽管他仍然非常愉快，却忍受了许多痛苦。1879年10月8日，他和妻子回到剑桥，但此时他几乎无法行走。这位世界所知的伟大科学家之一于11月5日去世。他的医生Paget医生说：-

没有人比他更自觉地、更平静地面对死亡。

James Clerk Maxwell was born at 14 India Street in Edinburgh, a house built by his parents in the 1820s.

You can see more about this house at THIS LINK.

Shortly afterwards his family moved to their home at Glenlair in Kirkcudbrightshire about 20 km from Dumfries. There he enjoyed a country upbringing and his natural curiosity displayed itself at an early age. In a letter written on 25 April 1834 when 'The Boy' was not yet three years old he is described as follows, see [3]:-

He is a very happy man, and has improved much since the weather got moderate; he has great work with doors, locks, keys etc., and 'Show me how it doos' is never out of his mouth. He also investigates the hidden course of streams and bell-wires, the way the water gets from the pond through the wall and a pend or small bridge and down a drain ...

When James was eight years old his mother died. His parents plan that they would educate him at home until he was 13 years old, and that he would then be able to go the Edinburgh University, fell through. A 16 year old boy was hired to act as tutor but the arrangement was not a successful one and it was decided that James should attend the Edinburgh Academy.

James, together with his family, arrived at 31 Heriot Row, the house of Isabella Wedderburn his father's sister, on 18 November 1841. He attended Edinburgh Academy where he had the nickname 'Dafty'. P G Tait, although almost the same age, was one class below James. Tait, who would become a close school friend and friend for life, described Maxwell's school days [42]:-

At school he was at first regarded as shy and rather dull. he made no friendships and spent his occasional holidays in reading old ballads, drawing curious diagrams and making rude mechanical models. This absorption in such pursuits, totally unintelligible to his schoolfellows, who were then totally ignorant of mathematics, procured him a not very complimentary nickname. About the middle of his school career however he surprised his companions by suddenly becoming one of the most brilliant among them, gaining prizes and sometimes the highest prizes for scholarship, mathematics, and English verse.

In early 1846 at the age of 14, Maxwell wrote a paper on ovals. In this work he generalised the definition of an ellipse by defining the locus of a point where the sum of $m$ times the distance from one fixed point plus $n$ times the distance from a second fixed point is constant. If $m = n = 1$ then the curve is an ellipse. Maxwell also defined curves where there were more than two foci. This became his first paper On the description of oval curves, and those having a plurality of foci which was read to the Royal Society of Edinburgh on 6 April 1846. These ideas were not entirely new as Descartes had defined such curves before but the work was remarkable for a 14 year old.

Maxwell was not dux of the Edinburgh Academy, this honour going to Lewis Campbell who later became the professor of Greek at the University of St Andrews. Lewis Campbell was a close friend of Maxwell's and he wrote the biography [3] and its second edition [4]. These biographies make fascinating reading filled with personal memories.

At the age of 16, in November 1847, Maxwell entered the second Mathematics class taught by Kelland, the natural philosophy (physics) class taught by Forbes and the logic class taught by William Hamilton. Tait, also at the University of Edinburgh, later wrote in the Proceedings of the Royal Society of Edinburgh (1879-80) [6]:-

The winter of 1847 found us together in the classes of Forbes and Kelland, where he highly distinguished himself. With the former he was a particular favourite, being admitted to the free use of the class apparatus for original experiments. ... During this period he wrote two valuable papers which are published in our Transactions, on 'The Theory of Rolling Curves and The Equilibrium of Elastic Solids'.

The University of Edinburgh still has a record of books that Maxwell borrowed to take home while an undergraduate. These include

Cauchy, Calcul Différentiel
Fourier, Théorie de la Chaleur
Monge, Géometrie Descriptive
Newton, Optics
Poisson, Mechanics
Taylor, Scientific Memoirs
Willis, Principles of Mechanism

Maxwell went to Peterhouse Cambridge in October 1850 but moved to Trinity where he believed that it was easier to obtain a fellowship. Again we quote Tait's article in the Proceedings of the Royal Society of Edinburgh (1879-80):-

... he brought to Cambridge in the autumn of 1850, a mass of knowledge which was really immense for so young a man, but in a state of disorder appalling to his methodical private tutor. Though the tutor was William Hopkins, the pupil to a great extent took his own way, and it may safely be said that no high wrangler of recent years ever entered the Senate-house more imperfectly trained to produce 'paying' work than did Clerk Maxwell. But by sheer strength of intellect, though with the very minimum of knowledge how to use it to advantage under the conditions of the Examination, he obtained the position of Second Wrangler, and was bracketed equal with the Senior Wrangler, in the higher ordeal of the Smith's Prizes.

Thomson [42] describes Maxwell's undergraduate days:-

... Scholars dined together at one table. This brought Maxwell into daily contact with the most intellectual set in the College, among whom were many who attained distinction in later life. These in spite of his shyness and some eccentricities recognised his exceptional powers. ... The impression of power which Maxwell produced on all he met was remarkable; it was often much more due to his personality than to what he said, for many found it difficult to follow him in his quick changes from one subject to another, his lively imagination started so many hares that before he had run one down he was off on another.

Maxwell obtained his fellowship and graduated with a degree in mathematics from Trinity College in 1854. The First Wrangler in that year was Edward Routh, who as well as being an excellent mathematician was a genius at mastering the cramming methods required to succeed in the Cambridge Tripos of that time. Maxwell remained at Cambridge where he took pupils, then was awarded a Fellowship by Trinity to continue work.

One of Maxwell's most important achievements was his extension and mathematical formulation of Michael Faraday's theories of electricity and magnetic lines of force. His paper On Faraday's lines of force was read to the Cambridge Philosophical Society in two parts, 1855 and 1856. Maxwell showed that a few relatively simple mathematical equations could express the behaviour of electric and magnetic fields and their interrelation.

However, in early 1856, Maxwell's father became ill and Maxwell wanted to be able to spend more time with him. He therefore tried to obtain an appointment in Scotland, applying for the post of Professor of Natural Philosophy at Marischal College in Aberdeen when Forbes told him it was vacant. Maxwell travelled to Edinburgh for the Easter vacation of 1856 to be with his father and the two went together to Glenlair. On 3 April his father died and, shortly after, Maxwell returned to Cambridge as he had planned. Before the end of April he learnt that he had been appointed to the chair at Marischal College.

In November 1856 Maxwell took up the appointment in Aberdeen. When the subject announced by St John's College Cambridge for the Adams Prize of 1857 was The Motion of Saturn's Rings Maxwell was immediately interested. Maxwell and Tait had thought about the problem of Saturn's rings in 1847 while still pupils at the Edinburgh Academy. Maxwell decided to compete for the prize and his research at Aberdeen in his first two years was taken up with this topic. He showed that stability could be achieved only if the rings consisted of numerous small solid particles, an explanation now confirmed by the Voyager spacecraft. In a letter to Lewis Campbell, written on 28 August 1857, while he was at Glenlair, Maxwell wrote:-

I have effected several breaches in the solid ring, and now am splash into the fluid one, amid a clash of symbols truly astounding. When I reappear it will be in the dusky ring, which is something like the siege of Sebastopol conducted from a forest of guns 100 miles one way, and 30,000 miles the other, and the shot never to stop, but go spinning away round a circle, radius 170,000 miles...

Maxwell's essay won him the Adams Prize and Airy wrote:-

It is one of the most remarkable applications of mathematics to physics that I have ever seen.

Maxwell became engaged to marry Katherine Mary Dewar in February 1858 and they married in June 1859. Despite the fact that he was now married to the daughter of the Principal of Marischal College, in 1860, when Marischal College and King's College combined, Maxwell, as the junior of the department, had to seek another post. His scientific work, however, had been proceeding with great success. Stokes had written to him on 7 November 1857:-

I have just received your papers on the dynamical top, etc., and the account of experiments on the perception of colour. The latter, which I missed seeing at the time when it was published, I have just read with great interest. The results afford most remarkable and important evidence in favour of the theory of three primary colour-perceptions, a theory which you, and you alone, as far as I know, have established on an exact numerical basis.

When the Chair of Natural Philosophy at Edinburgh became vacant in 1859, Forbes having moved to St Andrews, it seemed that fate had smiled on Maxwell to bring him back to his home town. He asked Faraday to act as a referee for him, in a letter written on 30 November 1859. Many of Maxwell's friends were also applicants for this post including Tait and Routh. Maxwell lost out to Tait despite his outstanding scientific achievements. When the Edinburgh paper, the Courant, reported the result it noted that:-

Professor Maxwell is already acknowledged to be one of the most remarkable men known to the scientific world.

The reason he was not appointed must have been those given by the paper when they wrote:-

... there is another quality which is desirable in a Professor in a University like ours and that is the power of oral exposition proceeding on the supposition of imperfect knowledge or even total ignorance on the part of pupils.

The claim that he was not the best person to teach poorly qualified pupils may have been a fair one but it is certainly not the case that he was a poor lecturer. Stokes wrote in 1854 that he had:-

... once been present when [Maxwell] was giving an account of his geometrical researches to the Cambridge Philosophical Society, on which occasion I was struck with the singularly lucid manner of his exposition.

Again Fleming, who had attended Maxwell's lectures, expressed similar thoughts [22]:-

Maxwell in short had too much learning and too much originality to be at his best in elementary teaching. For those however who could follow him his teaching was a delight.

In 1860 Maxwell was appointed to the vacant chair of Natural Philosophy at King's College in London. The six years that Maxwell spent in this post were the years when he did his most important experimental work. The duties of the post were more demanding than those at Aberdeen. Campbell writes in [3]:-

There were nine months of lecturing in the year, and evening lectures to artisans, etc., were recognised as a part of the Professor's duties.

In London, around 1862, Maxwell calculated that the speed of propagation of an electromagnetic field is approximately that of the speed of light. He proposed that the phenomenon of light is therefore an electromagnetic phenomenon. Maxwell wrote the truly remarkable words:-

We can scarcely avoid the conclusion that light consists in the transverse undulations of the same medium which is the cause of electric and magnetic phenomena.

Maxwell also continued work he had begun at Aberdeen, considering the kinetic theory of gases. By treating gases statistically in 1866 he formulated, independently of Ludwig Boltzmann, the Maxwell-Boltzmann kinetic theory of gases. This theory showed that temperatures and heat involved only molecular movement.

This theory meant a change from a concept of certainty, heat viewed as flowing from hot to cold, to one of statistics, molecules at high temperature have only a high probability of moving toward those at low temperature. Maxwell's approach did not reject the earlier studies of thermodynamics but used a better theory of the basis to explain the observations and experiments.

Maxwell left King's College, London in the spring of 1865 and returned to his Scottish estate Glenlair. He made periodic trips to Cambridge and, rather reluctantly, accepted an offer from Cambridge to be the first Cavendish Professor of Physics in 1871. He designed the Cavendish laboratory and helped set it up. The Laboratory was formally opened on 16 June 1874.

The four partial differential equations, now known as Maxwell's equations, first appeared in fully developed form in Electricity and Magnetism (1873). Most of this work was done by Maxwell at Glenlair during the period between holding his London post and his taking up the Cavendish chair. They are one of the great achievements of 19th -century mathematics.

One of the tasks which occupied much of Maxwell's time between 1874 and 1879 was his work editing Henry Cavendish's papers. Cavendish, see [14]:-

... published only two papers [and] left twenty packages of manuscript on mathematical and experimental electricity. ... Maxwell entered upon this work with the utmost enthusiasm: he saturated his mind with the scientific literature of Cavendish's period; he repeated many of his experiments, and copied out the manuscript with his own hand. ... The volume entitled 'The Electrical Researches of the Honourable Henry Cavendish' was published in 1879, and is unequalled as a chapter in the history of electricity.

Fleming attended Maxwell's last lecture course at Cambridge. He writes [22]:-

During the last term in May 1879 Maxwell's health evidently began to fail, but he continued to give his lectures up to the end of the term. ... To have enjoyed even a brief personal acquaintance with Professor Maxwell and the privilege of his oral instruction was in itself a liberal education, nay more, it was an inspiration, because everything he said or did carried the unmistakable mark of a genius which compelled not only the highest admiration but the greatest reverence as well.

Maxwell returned with his wife, who was also ill, to Glenlair for the summer. His health continued to deteriorate and he suffered much pain although remained remarkably cheerful. On 8 October 1879 he returned with his wife to Cambridge but, by this time he could scarcely walk. One of the greatest scientists the world has known died on 5 November. His doctor, Dr Paget, said:-

No man ever met death more consciously or more calmly.