Physicists From Scotland

"I have now studied the Theory of medicine & have likewise been taught every thing upon the Practice which can be learned in a College. I have also seen some real Practice & have even practised a little myself. But all this is not enough."

"In my last letter to you I proposed to go immediately to London to spend some time in the Hospitals there. I am now advised to put that off and remain here yet a while longer; & I must own the reasons for it are very strong quite unanswerable by me unless you disapprove of them. The following are the chief of them."

"I am not yet installed into the order of the great wig, but have gone through all the examinations, & nothing is wanting but the ceremony, that has been put off by the Processors to wait for some others that are to be promoted along with me 6 days hence."

"Your happiness on the contrary is quite secure because you place it entirely in making others happy and doing those things to the utmost of your power which you can afterwards reflect upon with satisfaction. I must own your letter had that effect upon me that it made me apply to my work with double eagerness and alacrity with the hopes of being some time what you are at present."

"Others in the pursuits after happiness or pleasure must commonly seek those sources of it which they cannot enjoy without some inconvenience to the rest of their fellow creatures; hence they have their imaginary happiness so much soured by Envy, Jealousy, or self-disapprobation that they find themselves dissappointed."

"Most Honrd Sir Your most affectionate letter of the 8th Aprill shews you in such a light as must warm the heart of a son with the highest degree of gratitude and affection."

"I thank God humbly and sincerely. God, who has visited us with many trials, and led us like the Israelites of old from place to place without any certain abode, bless, we beseech Thee, our return home, and mercifully grant that the afflictions and anxieties of that long probation may bear fruit in a more self-denying and godly life ; and that we may have our hearts fixed on a yet more abiding resting-place, eternal in the heavens, for Jesus Christ's sake.'"

"Of all the characters I have read of in history, no nature seems to me so like that of my friend, as that of Blaise Pascal, — with many important modifications be it said. There was the same sensitive organization ; the same intense love of truth for its own sake ; the same fearlessness in facing facts, however they might militate against preconceived notions, or established theories ; the same bright intelligence which to the end triumphed over the exhaustion of the bodily frame ; the same unquestioning submission of will and intellect to the Supreme Being; the same lowly acceptance of the super-natural truths of religion, how incomprehensible soever to man's weakness. . . his was a religion rather of hope than of fear. I never saw in any man such fearlessness in the path of duty. The one question with him was. Is it right ? No dread of consequences, and consequences often bitterly felt by him, and wounding his sensitive nature, ever prevented him from doing that to which conscience prompted."

"I have no scruple in expressing my convictions that you are destined to do something important in science, and under this conviction I am confident that there is no object of ambition worthy of your pursuit, but that of original discovery."

"Most merciful and gracious God, who hast preserved me unto this hour, I most humbly acknowledge Thee as the guide and companion of my youth. Thou hast protected me through the dangers of infancy and childhood, and in my youth Thou didst bless me with the full enjoyment, the happy intimacy, of the best of fathers. Be as gracious and merciful then as Thou hast hitherto been, now that I am about to enter a new stage of existence. Teach me, I beseech Thee, to strengthen in my soul the cultivation of Thy truth, the recollection of the uncertainty of life, the greatness of the objects for which I was created. Revive those delightful religious impressions which in early days I felt more strongly than now ; and as Thou hast been pleased lately to permit me to look to a way of life to which formerly I dared not to do, let the leisure I shall enjoy enlarge my warmth of heart towards Thee. Make every branch of study which I may pursue strengthen my confidence in Thy ever-ruling providence, that, undeceived by views of false philosophy, I may ever in singleness of heart elevate my mind from Thy works unto Thy divine essence. Keep from me a vain and overbearing spirit ; let me- ever have a thorough sense of my own ignorance and weakness ; and keep me through all the trials and troubles of a transitory state in body and soul unto everlasting life, for Jesus Christ's sake. Amen.'"

"Another evil, and one of the worst which arises from the separation of theoretical and practical knowledge, is the fact that a large number of persons, possessed of an inventive turn of mind and of considerable skill in the manual operations of practical mechanics, are destitute of that knowledge of scientific principles which is requisite to prevent their being misled by their own ingenuity. Such men too often spend their money, waste their lives, and it may be lose their reason in the vain pursuits of visionary inventions, of which a moderate amount of theoretical knowledge would be sufficient to demonstrate the fallacy ; and for want of such knowledge, many a man who might have been a useful and happy member of society, becomes a being than whom it would be hard to find anything more miserable. The number of those unhappy persons — to judge from the patent-lists, and from some of the mechanical journals — must be much greater than is generally believed."

"We have... used the word stress to denote the mutual action between two portions of matter. This word was borrowed from common language, and invested with a precise scientific meaning by the late Professor Rankine to whom we are indebted for several other valuable scientific terms."

"Science Of Energetics. Although the mechanical hypothesis just mentioned may be useful and interesting as a means of anticipating laws, and connecting the science of thermodynamics with that of ordinary mechanics, still it is to be remembered that the science of thermodynamics is by no means dependent for its certainty on that or any other hypothesis, having been now reduced, to a system of principles, or general facts, expressing strictly the results of experiment as to the relations between heat and motive power. In this point of view the laws of thermodynamics may be regarded as particular cases of more general laws, applicable to all such states of matter as constitute Energy, or the capacity to perform work, which more general laws form the basis of the science of energetics, — a science comprehending, as special branches, the theories of motion, heat, light, electricity, and all other physical phenomena."

"Hypothesis Of Molecular Vortices. In thermodynamics as well as in other branches of molecular physics, the laws of phenomena have to a certain extent been anticipated, and their investigation facilitated, by the aid of hypotheses as to occult molecular structures and motions with which such phenomena are assumed to be connected. The hypothesis which has answered that purpose in the case of thermodynamics, is called that of "molecular vortices," or otherwise, the "centrifugal theory of elasticity. (On this subject, see the Edinburgh Philosophical Journal, 1849; Edinburgh Transactions, vol. xx.; and Philosophical Magazine, passim, especially for December, 1851, and November and December, 1855.)"

"It is possible to express the laws of thermodynamics in the form of independent principles, deduced by induction from the facts of observation and experiment, without reference to any hypothesis as to the occult molecular operations with which the sensible phenomena may be conceived to be connected; and that course will be followed in the body of the present treatise. But, in giving a brief historical sketch of the progress of thermodynamics, the progress of the hypothesis of thermic molecular motions cannot be wholly separated from that of the purely inductive theory."

"But in practical science, the question is—What are we to do?—a question which involves the necessity for the immediate adoption of some rule of working. In doubtful cases, we cannot allow our machines and our works of improvement to wait for the advancement of science; and if existing data are insufficient to give an exact solution of the question, that approximate solution must be acted upon which the best data attainable show to be the most probable. A prompt and sound judgment in cases of this kind is one of the characteristics of a Practical Man in the right sense of that term."

"In theoretical science, the question is—What are we to think? and when a doubtful point arises, for the solution of which either experimental data are wanting, or mathematical methods are not sufficiently advanced, it is the duty of philosophic minds not to dispute about the probability of conflicting suppositions, but to labour for the advancement of experimental inquiry and of mathematics, and await patiently the time when they shall be adequate to solve the question."

"In treating of the practical application of scientific principles, an algebraical formula should only be employed when its shortness and simplicity are such as to render it a clearer expression of a proposition or rule than common language would be, and when there is no difficulty in keeping the thing represented by each symbol constantly before the mind."

"[T]he symbols of algebra, when employed in abstruse and complex theoretical investigations, constitute a sort of thought-saving machine, by whose aid a person skilled in its use can solve problems respecting quantities, and dispense with the mental labour of thinking of the quantities denoted by the symbols, except at the beginning and the end of the operation."

"Sir John Herschel's "Outlines of Astronomy"—[is] a work in which one of the most profound mathematicians in the world has succeeded admirably in divesting of all mathematical intricacy the explanation of the principles of that natural science which employs higher mathematics most."

"In the original discovery of a proposition of practical utility, by deduction from general principles and from experimental data, a complex algebraical investigation is often not merely useful, but indispensable; but in expounding such a proposition as a part of practical science, and applying it to practical purposes, simplicity is of the importance:—and... the more thoroughly a scientific man has studied higher mathematics, the more fully does he become aware of this truth—and... the better qualified does he become to free the exposition and application of principles from mathematical intricacy."

"The third and intermediate kind of instruction, which connects the first two... relates to the application of scientific principles to practical purposes. It qualifies the student to plan a structure or a machine for a given purpose, without the necessity of copying some existing example, and to adapt his designs to situations to which no existing example affords a parallel. It enables him to compute the theoretical limit of the strength or stability of a structure, or the efficiency of a machine of a particular kind—to ascertain how far an actual structure or machine fails to attain that limit—to discover the cause of such shortcomings—and to devise improvements for obviating such causes; and it enables him to judge how far an established practical rule is founded on reason, how far on mere custom, and how far on error."

"The ascertainment and illustration of truth are the objects; and structures and machines are looked upon merely as natural bodies are; namely, as furnishing experimental data for the ascertaining of principles and examples for their application."

"In this branch of study exactness is an essential feature; and mathematical difficulties must not be shrunk from when the nature of the subject leads to them."

"The objects of instruction in purely scientific mechanics and physics are, first, to produce in the student that improvement of the understanding which results from the cultivation of natural knowledge, and that elevation of mind which flows from the contemplation of the order of the universe; and secondly, if possible, to qualify him to become a scientific discoverer."

"Mechanical knowledge may... be distinguished into three kinds; purely scientific knowledge, purely practical knowledge, and that intermediate kind of knowledge which relates to the application of scientific principles to practical purposes, and which arises from understanding the harmony of theory and practice."

"Some of the evils which are caused by the fallacy of an incompatibility between theory and practice having been described, it must now be admitted, that at the present time those evils show a decided tendency to decline. The extent of intercourse, and of mutual assistance, between men of science and men of practice, the practical knowledge of scientific men, and the scientific knowledge of practical men, have been for some time steadily increasing; and that combination and harmony of theoretical and practical knowledge—that skill in the application of scientific principles to practical purposes, which in former times was confined to a few remarkable individuals, now tends to become more generally diffused."

"The ill-success of the projects of misdirected ingenuity has very naturally the effect of driving those men of practical skill, who, though without scientific knowledge, possess prudence and common sense, to the opposite extreme of caution, and of inducing them to avoid all experiments, and to confine themselves to the careful copying of successful existing structures and machines; a course which, although it avoids risk, would, if generally followed, stop the progress of all improvement. A similar course has sometimes... been adopted by men possessed of scientific as well as practical skill: such men having, in certain cases, from deference to popular prejudice, or from a dread of being reputed us theorists, considered it advisable to adopt the worse and customary design for a work in preference to a better but unusual design."

"The most absurd of all their delusions commonly called the , or to speak more accurately, the inexhaustible source of power—is, in various forms, the subject of several patents in each year."

"But a class of structures fraught with much greater evils exist in great abundance throughout the country—namely, those in which the faults of an unscientific design have been so far counteracted by massive strength, good materials, and careful workmanship, that a temporary stability has been produced, but which contain within themselves sources of weakness, obvious to a scientific examination... that must inevitably cause their destruction within a limited number of years."

"With respect to those works which, from unscientific design, give way during or immediately after their erection, I shall say little; for with all their evils, they add to our experimental knowledge, and convey a lesson, though a costly one."

"[O]f that scientifically practical skill which produces the greatest effect with the least possible expenditure of material and work, the instances are comparatively rare. In too many cases we see the strength and the stability which ought to be given by the skilful arrangement of the parts of a structure supplied by means of clumsy massiveness, and of lavish expenditure of material, labour, and money; and the evil is increased by a perversion of the public taste, which causes works to be admired, not in proportion to their fitness for their purposes, or to the skill evinced in attaining that fitness, but in proportion to their size and cost."

"The evil influence of the supposed inconsistency of theory and practice upon speculative science, although much less conspicuous than it was in the ancient and middle ages, is still occasionally to be traced. This it is which opposes the mutual communication of ideas between men of science and men of practice, and which leads scientific men sometimes to employ, on problems that can only be regarded as ingenious mathematical exercises, much time and mental exertion that would be better bestowed on questions having some connection with the arts, and sometimes to state the results of really important investigations on practical subjects in a form too abstruse for ordinary use; so that the benefit which might be derived from their application is for years lost to the public; and valuable practical principles which might have been anticipated by reasoning, are left to be discovered by slow and costly experience."

"A hypothetical theory is necessary, as a preliminary step, to reduce the expression of the phenomena to simplicity and order before it is possible to make any progress in framing an abstractive theory."

"A physical theory, like an abstract science, consists of definitions and axioms as first principles, and of propositions, their consequences; but with these differences:—first, That in an abstract science, a definition assigns a name to a class of notions derived originally from observation, but not necessarily corresponding to any existing objects of real phenomena, and an axiom states a mutual relation amongst such notions, or the names denoting them; while in a physical science, a definition states properties common to a class of existing objects, or real phenomena, and a physical axiom states a general law as to the relations of phenomena; and, secondly,—That in an abstract science, the propositions first discovered are the most simple; whilst in a physical theory, the propositions first discovered are in general numerous and complex, being formal laws, the immediate results of observation and experiment, from which the definitions and axioms are subsequently arrived at by a process of reasoning differing from that whereby one proposition is deduced from another in an abstract science, partly in being more complex and difficult, and partly in being to a certain extent tentative, that is to say, involving the trial of conjectural principles, and their acceptance or rejection according as their consequences are found to agree or disagree with the formal laws deduced immediately from observation and experiment."

"An essential distinction exists between two stages in the process of advancing our knowledge of the laws of physical phenomena; the first stage consists in observing the relations of phenomena, whether of such as occur in the ordinary course of nature, or of such as are artificially produced in experimental investigations, and in expressing the relations so observed by propositions called formal laws. The second stage consists in reducing the formal laws of an entire class of phenomena to the form of a science; that is to say, in discovering the most simple system of principles, from which all the formal laws of the class of phenomena can be deduced as consequences."

"This law (regarding the theoretical efficiency of heat engines by Mr. Joule), and the law of the maximum efficiency of heat engines, are particular cases of a general law which regulates all transformation of energy, and is the basis of the Science of Energetics."

"Discrepancy between theory and practice, which in sound physical and mechanical science is a delusion, has a real existence in the minds of men; and that fallacy, through rejected by their judgments, continues to exert and influence over their acts."

"The hypothesis of molecular vortices is defined to be that which assumes — that each atom of matter consists of a nucleus or central point enveloped by an elastic atmosphere, which is retained in its position by attractive forces, and that the elasticity due to heat arises from the centrifugal force of those atmospheres revolving or oscillating about their nuclei or central points. According to this hypothesis, quantity of heat is the vis viva of the molecular revolutions or oscillations."

"What may appear as a towering peak to one may seem but an ordinary eminence to another."

"We are perhaps too near the age of transition to see clearly the interplay of all that made for progress. Each of us has had his own peculiar training, his own personal contact with the mighty ones of the immediate past; and this forms as it were a telescopic tube determining limits to our field of vision. No doubt we may range the whole horizon; but after all we look from our own point of vantage."

"Scientific theory and its application to the growing needs of mankind advance hand in hand."

"The next grand extensions of mathematical physics will, in all likelihood, be furnished by quaternions."

"[Examiners] spend their lives in discovering which pages of a text-book a man ought to read and which will not be likely to 'pay'."

"Oh, that's nothing – I could coach a coal scuttle to be Senior Wrangler."

"It is not within our province to inquire by what process, and in what condition the Almighty brought matter into existence-what the space was which it occupied, or what the forms were which it assumed. Of such things we know nothing. In the depths of primeval time, the globe we inhabit may have a planetary existence, wheeling along its ethereal railway without a breathing passenger to count its periods, and without a living plant to measure the day by its opening and closing blossoms, or to mark the rolling seasons by the yearly increments of its stem. Or it may have been the theatre on which vast cycles of animal and vegetable life have been run- now its birthplace, and now its grave: But we have no data to guide us in our conjectures, and even imagination fails us if we call it to our aid. Whatever may have been, had ceased to be at the commencement of our history, when the primary rocks, forming the moten nucleus of the globe, were first exposed to the action of the elements."

"The only sure mode of acquiring sound ideas of our relation to the Creator is to begin with the study of ourselves, and to view God as a Father and Friend, dealing with us in precisely the same way as we would deal with others over whom we exercise authority. Conscience, that infallible Mentor "that sticketh closer than a brother," tells us that we are responsible beings; and in the domestic, as well as the social circle, we speedily feel the discipline and learn the lesson of rewards and punishments. The law written in man's heart points to the past as pregnant with events which may affect the future; and in the earnestness of his aspirations, and the activity of his search, he is gradually led to the mysterious history of his race. He learns that on tables of stone have been engraven the same law to which his heart responded; -that when all were dead, one died for all; and in the contemplation of the great sacrifice, he obtains a solution of the interesting problem of his individual destiny. The Sacred record which is now his guide, speaks to him of fore-knowledge and predestination, while, in perfect consistency, it records the ministration of descending spirits, and the holier communings of God with man. The Divine decrees no longer perplex him. They transcend, indeed, his Reason - but that Reason, the faithful interpreter of Conscience, does not falter in proclaiming the Freedom of his Will, and the Responsibility of his Actions."

"It is God alone that can pronounce upon the real condition of the heart and soul, out of which are the issues of life. A true phrenological fact, therefore, which we can force a sound mind to believe must involve, in one of its aspects, a species of knowledge which ist is not in the power of man, and still less within his province, to attain; and in the other, a physical fact, which can be seen only in the brain itself, and which cannot be interfered from any external sign."

"If it has been revealed to man that the Almighty made him out of the dust of the earth, and breathed into his nostrils the breath of life, it is in vain to tell a Christian that man was originally a speck of albumen, and passed through the stages of monads and monkeys, before he attained his present intellectual preeminence. If it be a received truth that the Creator has repeatedly interposed in the government of the universe and displayed his immediate agency in miraculous interpositions, it is an insult to any reader to tell him that the being slumbers on his throne and rules under a "primal arrangement in his counsels," and "by a code of laws of unbending operation.""

"I would advise you not to expect too much happiness, even from the fulfillment of all your wishes. The moment you have distinguished yourself you become an object of envy and malice ; men whom you believed to be lovers of knowledge you will then find to be lovers only of fame, and haters of all knowledge that has not come from themselves. You will find that a life of science has in it no superiority to any other, unless it is pursued from a higher principle than the mere ambition of notoriety, and that demagogue or a philosopher differ only in the objects of their selfishness. As you will now have experienced how unsatisfying even the pursuit of knowledge is when insulated from higher objects, I hope, if you have not been fortunate enough to begin the study earlier, that you will devote yourself to the most extraordinary of all subjects, one which infinitely surpasses the mechanism of the heavens or the chemistry of the material world, the revelation of your duty and the destiny of man as contained in The Bible — a book which occupied the best hours of the manhood of Newton, of Locke, and of Euler."