Using Python for CI/CD Pipelines
Technical requirements
The origins and philosophy of CI/CD
Scene 1 – continuous integration
Scene 2 – continuous delivery
Scene 3 – continuous deployment
Python CI/CD essentials – automating a basic task
Working with devs and infrastructure to deliver your product
Performing rollback
Summary
Part 3: Let’s Go Further, Let’s Build Bigger
10
Common DevOps Use Cases in Some of the Biggest Companies in the World
AWS use case – Samsung electronics
Scenario
Brainstorming
Solution
Azure Use Case – Intertech
Scenario
Brainstorming
Solution
Google Cloud use case – MLB and AFL
Scenario
Brainstorming
Solution
Summary
11
MLOps and DataOps
Technical requirements
How MLOps and DataOps differ from regular DevOps
DataOps use case – JSON concatenation
MLOps use case – overclocking a GPU
Dealing with velocity, volume, and variety
Variety
The Ops behind ChatGPT
Summary
12
How Python Integrates with IaC Concepts
Technical requirements
Automation and customization with Python’s Salt library
How Ansible works and the Python code behind it
Automate the automation of IaC with Python
Summary
13
The Tools to Take Your DevOps to the Next Level
Technical requirements
Advanced automation tools
Advanced monitoring tools
Advanced event response strategies
Summary
Index
Other Books You May Enjoy
Preface
Welcome to this book! Let’s talk about the content of this book and what you will learn from it This book is about two things: DevOps and Python It is about how these two entities, philosophies, frameworks, or whatever you would like to call them interact with each other.
This book will help you understand Python on a technical level, but also on a conceptual level, including what distinguishes Python from a lot of other languages and what makes it so popular among programmers and others who provide IT solutions.
At the same time, it will give you perspective on how important and useful DevOps is in modern IT infrastructure and how you can implement the concepts of DevOps using Python.
You will learn how to make the hard stuff easy and how to solve problems in a consistent and sustainable way. You will also learn how to insert bits of Python code into your workload to smoothen your problem-solving process.
This book will go beyond just some technical descriptions and processes and will help you make your workflow and work process even better regardless of the tools you are using.
Another random document with no related content on Scribd:
"The Accent is always on the penultimate syllable. Esperanto reminds one of Italian, when spoken, and has proved extremely melodious for singing.
"The Vocabulary. The principle of internationalism is applied here in a most ingenious fashion. Dr. Zamenhof proceeded thus: he compared the dictionaries of the different languages, and picked out first those words which are common to them all. He spelled them according to the phonetic system, dropped the special endings in each idiom, and adopted them as root-words in his proposed language. … Then he picked out those which appear in most languages, although not in all. … For the remaining words, and there are comparatively few left, which are never the same in the different languages, Dr. Zamenhof selected them in such a manner as to make the task of acquiring Esperanto equally difficult or equally easy for all concerned."
A. Schinz, Esperanto: the Proposed Universal Language (Atlantic Monthly, January, 1906).
The sixth international Congress of teachers and promoters of Esperanto is appointed to be held at Washington in 1910. An influential Esperanto Association has been organized in the United States, under the presidency of Dr. D. O. S. Lowell, of the Boston Latin School.
SCIENCE AND INVENTION, RECENT: Eugenics: The Science and Art of being Well-born.
"We know that the old rule, ‘Increase and multiply,’ meant a vast amount of infant mortality, of starvation, of chronic disease, of widespread misery. In abandoning that rule, as we have been forced to do, are we not now left free to seek that our children, though few, should be at all events fit, the
finest, alike in physical and psychical constitution, that the world has seen?
"Thus has come about the recent expansion of that conception of eugenics or the science and art of being well-born, and of breeding the human race a step nearer towards perfection which a few among us, and more especially Mr. Francis Galton, have been developing for some years past. Eugenics is beginning to be felt to possess a living actuality which it was not felt to possess before. Instead of being a benevolent scientific fad, it begins to present itself as the goal to which we are inevitably moving. … Human eugenics need not be, and is not likely to be, a cold-blooded selection of partners by some outside scientific authority. But it may be, and is very likely to be, a slowly growing conviction first among the more intelligent members of the community, and then by imitation and fashion among the less intelligent members that our children, the future race, the torch-bearers of civilisation for succeeding ages, are not the mere result of chance or Providence, but that, in a very real sense, it is within our grasp to mould them, that the salvation or damnation of many future generations lies in our hands, since it depends on our wise and sane choice of a mate. …
"Eventually, it seems evident, a general system, whether private or public, whereby all personal facts, biological and mental, normal and morbid, are duly and systematically registered, must become inevitable if we are to have a real guide as to those persons who are most fit or least fit to carry on the race. Unless they are full and frank, such records are useless. But it is obvious that for a long time to come such a system of registration must be private. … Through the munificence of Mr. Galton and the co-operation of the University of London the beginning of the attainment of these eugenic ideals has at length been rendered possible. The senate of the University has this year appointed Mr. Edgar Schuster, of New College, Oxford, to the Francis Galton
Research Scholarship in Natural Eugenics. It will be Mr. Schuster’s duty to carry out investigations into the history of classes and of families, and to deliver lectures and publish memoirs on the subject of his investigations. It is a beginning only, but the end no man can foresee."
Havelock Ellis, Eugenics and St. Valentine (Nineteenth Century, May, 1906).
SCIENCE AND INVENTION, RECENT:
The Gasoline Engine.
Writing in 1905, in an article entitled "The Age of Gasoline," contributed to the American Review of Reviews, Mr. F. K. Grain, M. E., gave this brief account of the rapid development of its use as a producer of power, threatening to supersede coal: "About fifteen years ago we first began to hear much of the gasoline engine, which was then in a very crude state. Its possibilities, however, were so attractive, and the field for its use so large, practically unlimited, that inventors and manufacturers at once bent their energies to its development, with the result that the gasoline engine has reached a degree of perfection in the past few years that is surprising in view of the fact that the designers were working out a new problem in a practically unknown field, and consequently had no data, theoretical or practical, of any value to assist. … As a motive power, utilized by means of the internal-combustion engine, gasoline is at this time revolutionizing travel, through the automobile. The automobile, in turn, has been the means of adapting gasoline to propulsion of railway trains, as this form of power is found especially useful on short lines where the traffic is light. Several railroads are now building gasoline motor cars of considerable size. …
"The gasoline engine as now made is an adaptation of the steam
engine, employing the gas produced by gasoline as a means of energy. Contrary to the general understanding, the gas or gasoline engine is but a high-pressure caloric motor. The power in the gasoline motor is derived by igniting the gas produced in the cylinder, which in turn by its heat expands, the atmosphere imparting energy to the piston by its expansion. A common error is the supposition that the explosion of the gas produces the power, the same as a blow from a hammer, whereas it is the heat generated by the ignition of the compressed gases acting expansively."
One of the speakers at a Congress of Applied Chemistry held in London in May, 1909, said that it seemed almost certain that for most purposes on land the internal combustion engine would before long replace the steam engine, at any rate for moderate powers; for whereas the best types of the latter furnish only about 12 per cent, of the energy of the fuel in the form of work, the former can ordinarily be made to yield 25 per cent., and in the case of the Diesel engine the return is as much as 37 per cent.
{602}
SCIENCE AND INVENTION, RECENT: Interferometer, The: Principle of the Invention of Professor Michelson for Infinitesimal Measurements. Suggestion of an Unvarying Unit of Measurement.
"In the measurement of length or motion a most refined instrument is the interferometer, devised by Professor A. A. Michelson, of the University of Chicago. It enables an observer to detect a movement through one five-millionth of an inch. The principle involved is illustrated in a simple experiment. If by dropping a pebble at each of two centres, say a yard apart, in a still pond, we send out two systems of waves, each system will ripple out in a series of concentric circles. If, when the waves meet, the crests from one set of
waves coincide with the depressions from the other set, the water in that particular spot becomes smooth because one set of waves destroys the other. In this case we may say that the waves interfere. If, on the other hand, the crests of waves from two sources should coincide, they would rise to twice their original height. Light-waves sent out in a similar mode from two points may in like manner either interfere, and produce darkness, or unite to produce light of double brilliancy. These alternate dark and bright bands are called interference fringes. When one of the two sources of light is moved through a very small space, the interference fringes at a distance move through a space so much larger as to be easily observed and measured, enabling an observer to compute the short path through which a light-source has moved. … Many diverse applications of the interferometer have been developed, as, for example, in thermometry. The warmth of a hand held near a pencil of light is enough to cause a wavering of the fringes. A lighted match shows contortions. … When the air is heated its density and refractive power diminish: it follows that if this experiment is tried under conditions which show a regular and measurable displacement of the fringes, their movement will indicate the temperature of the air. This method has been applied to ascertain very high temperatures, such as those of the blast furnace. Most metals expand one or two parts in 100,000 for a rise in temperature of one degree centigrade. When a small specimen is examined the whole change to be measured may be only about 1/10000 inch, a space requiring a good microscope to perceive, but readily measured by an interferometer. It means a displacement amounting to several fringes, and this may be measured to within of a fringe or less; so that the whole displacement may be measured to within a fraction of one per cent. Of course, with long bars the accuracy attainable is much greater.
"The interferometer has much refined the indications of the balance. In a noteworthy experiment Professor Michelson found the amount of attraction which a sphere of lead exerted on a
small sphere hung on an arm of a delicate balance. The amount of this attraction when two such spheres touch is proportional to the diameter of the large sphere, which in this case was about eight inches. The attraction on the small ball on the end of the balance was thus the same fraction of its weight as the diameter of the large ball was of the diameter of the earth, something like one twenty-millionth. So the force to be measured was one twenty-millionth of the weight of this small ball. In the interferometer the approach of the small ball to the large one produced a displacement of seven whole fringes."
George Iles, Inventors at Work, pages 214-218 (Doubleday, Page & Co., New York).
SCIENCE AND INVENTION, RECENT: International Congresses of Science.
The most notable of the gatherings at St. Louis in 1904, connected with the Louisiana Purchase Exposition, was the Congress of Arts and Science.
See (in this Volume) ST. LOUIS: A. D. 1904.
Hardly less important from some points of view was the meeting of the First Pan-American Scientific Congress, at Santiago, Chile, beginning on the 25th of December, 1908. It had been preceded by three scientific congresses of the Latin-American states, at Buenos Aires in 1898, at Montevideo in 1901, and at Rio de Janeiro in 1905. The Pan-American comprehensiveness was given to a fourth one by an official invitation from the Chilean Government to the Government of the United States to send delegates to the meeting, and a further invitation from the Chilean Committee of Organization to fifteen of the prominent universities of the United States to do the same. The response to the invitation was cordial, and both of the
American continents were well represented at the Congress. The programme of topics for discussion included a number of historically and politically scientific questions of specially American interest, such, for example, as the following:
"An explanation of the reasons why the colonies of English America were able to unite into a single state after they had attained their independence, while those of Spanish America never succeeded in establishing a permanent union.
"The extent to which America has come to possess a civilization, as well as interests and problems, different from those of Europe.
"Given the special circumstances of the states of the New World, would it be feasible to create an American international law? and if so, upon what bases should it rest, and how should it be composed?"
SCIENCE AND INVENTION, RECENT: The Moving Picture Show. The Millions entertained by it in the United States.
In 1908, in the United States, "the moving-picture show drew an attendance of 4,000,000 daily, a total attendance of more than a billion; or an average of one visit a month to this form of amusement for every man, woman, and child in the whole country. Already this infant industry has developed to a point where $50,000,000 is invested in it, and 7,000 moving-picture houses are scattered over the country. Of the larger cities, Chicago has at present 313 moving-picture shows, and probably will have 500 before the end of the present year. New York has 300, St. Louis 205, Philadelphia 186, San Francisco 131, Pittsburgh 90, and Boston 31. Hundreds of smaller cities and towns have from one to a dozen, and the craze has extended to Mexico, Central and South America, and the Panama Canal Zone. Nearly 1,000,000 feet, or 190 miles, of films are shown every day in the United States. … Making of these films is in itself
an enormous business. The organization which controls them not only has agents photographing scenes in every part of the world, but maintains theatres and out-of-door establishments, where complete plays and all sorts of other activities are presented before the camera."
New York Evening Post.
{603}
SCIENCE AND INVENTION, RECENT: Opsonins: A remarkable new Discovery in Biology.
Discovery of the functions of the white corpuscles found in the blood of animals was begun, it is said, by Dr. Augustus Waller, in 1843, and continued in much later years by Professor Metchnikoff, who was associated with the work of Pasteur. The latter determined the surprising and extremely important fact that the white corpuscles or cells are essentially minute living creatures, which serve the larger creature they inhabit as a sanitary guard, defending it against the invasion of microbes that are hostile to its health. They pursue and devour these malignant invaders; whence the name that has been given to them, of "phagocytes," or "eating cells."
"When we study the process familiarly known as ‘inflammation,’ we find the most perfect illustration at once of the duties of the white blood-cells and of the new phase and meaning of a common occurrence which are revealed by research. ‘Inflammation’ is a process which follows upon a large variety of injuries, and which marks the onset and course of many diseases, from a scratch on the finger to an inflammation of the lungs. … Given a simple scratch and the phagocytes stimulated by the injury to the tissues will come hurrying to the scene of the accident like ambulance men, eager to assist in the removal of any deleterious matter, and to give their
aid in the healing process and in the formation of the new tissue, the production of which will complete the cure. But given a scratch that inoculates the finger with ‘dirt,’ which is only another name for microbes, and the nature of inflammation becomes clearer to us. In a few hours the finger will begin to feel painful; its temperature will rise; it will appear red and ‘inflamed,’ and it will exhibit swelling. Later on, if we puncture the swelling, we shall find a yellow fluid, which we name ‘pus,’ or ‘matter,’ escaping from the puncture. Now to what are the symptoms of inflammation due? The plain answer is, that they represent the results of a great migration of phagocytes from the blood-vessels, destined to attack, and if possible remove, the infective particles which threaten to do us injury. The inflammation, in this view, is the evidence of a battle being fought in our favour, and often with very long odds against us. If our phagocytes gain a complete victory, we escape the suppuration which we saw to result in the shape of the ‘festering’ finger. If, on the other hand, they sustain defeat, they will fight on, leaving their dead behind. It is the dead white blood-cells, which have fallen in the fray, which constitute the ‘pus’ or ‘matter’ we find in wounds. … These dead cells, like the corpses of soldiers who fall in battle, later become hurtful to the organism they in their lifetime were anxious to protect from harm, for they are fertile sources of septicaemia and pyaemia (blood-poisoning) the pestilence and scourge so much dreaded by operative surgeons.
"Such is the story which forms the natural prologue to the history of ‘Opsonins.’ For many a day after the publication of Metchnikoff’s discoveries regarding the germ-killing power of the phagocytes, it was held that these living cells alone accomplished the duty of disposing of troublesome invaders. Later on, other opinions were advanced to the effect that while the phagocytes did undoubtedly accomplish their work in the direction indicated, they demanded aid to that end from an outside source. This source was indicated and represented by
the plasma or blood-fluid itself. The fluid part of the blood had long been known to possess germ-killing properties, but the extent of its powers in this direction had not been duly determined, nor had the important point been settled whether the plasma as a whole or only part thereof aided the white blood-cells in their forays on microbes. … Researches made prior to the year 1903 gave cause for the belief in the importance of the blood-plasma in whole or in part, but it was in the year just named that very important investigations were undertaken with the view to determining the exact status of the blood-fluid in work of bactericidal kind. Drs. Wright and Douglas of St. Mary’s Hospital, London, undertook a piece of research conducted on lines somewhat different from those on which previous work of this nature had been carried on. They proceeded first of all by the aid of delicate processes to separate the blood-corpuscles from the blood-fluid. The white blood-cells were thus kept in a medium or fluid of neutral kind, while the blood-fluid itself on the other hand was obtained free from its corpuscles. Next in order an emulsion of certain microbes capable of producing disease was made in a solution of salt. When the phagocytes, alive, of course, in their neutral fluid, were allowed access to the germs they did not attack them. It was as if two contending armies had been brought face to face, waiting to attack, but restrained by some negotiations proceeding between the commanders. The case was at once altered, and the battle began, when the experimenters brought the separated blood-fluid into the field. Added to the germs and to the phagocytes these elements, which had been ‘spoiling for a fight,’ joined issue, and the white blood-cells performed their normal work of microbe-baiting. There was but one inference to be drawn from these facts. Clearly, the addition of the blood-fluid supplied some condition or other, necessary for the development of the fighting powers of the cells. … Our investigators are of the opinion that the real source of the power possessed by the blood-fluid or ‘plasma’ is to be sought and found in substances contained therein and called ‘Opsonins.’ We can now
appreciate the meaning of this term. It is derived from the classic verb for catering, for preparing food or for providing food. The view taken of opsonic action justifies the use of the word, for it is believed that these substances perform their share of the germ-destroying work, not by urging on or stimulating the phagocytes to the attack, but, on the contrary, by acting on the microbes, by weakening their powers of resistance and by rendering them the easy prey of the white blood-cells. The ‘Opsonins’ are carried by the blood-stream everywhere, and it is when they come in contact with any microbe-colonies in the body that they exert their specific action on the germs. … The idea that the more active our white blood-cells are, and the more extensive and complete their work, the greater the amount of ‘Opsonins’ present, is one which seems to be founded on a rational basis. This view regards these substances as the real cause of phagocytic activity. That ‘Opsonins’ furthermore appear to possess definite degrees of power seems proved by the observation that a person’s blood may contain sufficient to deal with one disease in the way of stimulating the phagocytes to work, while the same quantity would not equal half that required to effect a satisfactory attack on another and different disease. What has been called the ‘opsonic index ’ of a person is the standard, if so we may call it, or measure of his germ-killing power, in so far as the amount of ‘Opsonins’ contained in his blood is concerned. By a technical procedure and calculation the experimenter can compute the opsonic power of a given specimen of blood."
Wilson, About Opsonins
(Cornhill,
January, 1907).
{604}
SCIENCE AND INVENTION, RECENT: Medical.
Andrew
See (in this Volume) PUBLIC HEALTH.
SCIENCE AND INVENTION, RECENT: Physical: The New Conceptions of Electricity, Matter and Ether. Statement by Madame Curie.
Sir Joseph Thomson’s Address to the British Association at Winnipeg.
Sir Oliver Lodge on the Ether of Space.
"One point which appears to-day to be definitely settled is a view of atomic structure of electricity, which goes to confirm and complete the idea that we have long held regarding the atomic structure of matter, which constitutes the basis of chemical theories. At the same time that the existence of electric atoms, indivisible by our present means of research, appears to be established with certainty, the important properties of these atoms are also shown. The atoms of negative electricity which we call electrons, are found to exist in a free state, independent of all material atoms, and not having any properties in common with them. In this state they possess certain dimensions in space, and are endowed with a certain inertia, which has suggested the idea of attributing to them a corresponding mass.
"Experiments have shown that their dimensions are very small compared with those of material molecules, and that their mass is only a small fraction, not exceeding one one-thousandth of the mass of an atom of hydrogen. They show also that if these atoms can exist isolated, they may also exist in all ordinary matter, and may be in certain cases emitted by a substance such as a metal without its properties being changed in a manner appreciable by us.
"If, then, we consider the electrons as a form of matter, we are led to put the division of them beyond atoms and to admit the existence of a kind of extremely small particles able to
enter into the composition of atoms, but not necessarily by their departure involving atomatic destruction. Looking at it in this light, we are led to consider every atom as a complicated structure, and this supposition is rendered probable by the complexity of the emission spectra which characterize the different atoms. We have thus a conception sufficiently exact of the atoms of negative electricity.
"It is not the same for positive electricity, for a great dissimilarity appears to exist between the two electricities. Positive electricity appears always to be found in connection with material atoms, and we have no reason, thus far, to believe that they can be separated. Our knowledge relative to matter is also increased by an important fact. A new property of matter has been discovered which has received the name of radioactivity. Radioactivity is the property which the atoms of certain substances possess of shooting off particles, some of which have a mass comparable to that of the atoms themselves, while the others are the electrons. This property, which uranium and thorium possess in a slight degree, has led to the discovery of a new chemical element, radium, whose radioactivity is very great. Among the particles expelled by radium are some which are ejected with great velocity, and their expulsion is accompanied with a considerable evolution of heat. A radioactive body constitutes, then, a source of energy.
"According to the theory which best accounts for the phenomena of radioactivity, a certain proportion of the atoms of a radioactive body is transformed in a given time, with the production of atoms of less atomic weight, and in some cases with the expulsion of electrons. This is a theory of the transmutation of elements, but differs from the dreams of the alchemists in that we declare ourselves, for the present at least, unable to induce or influence the transmutation. Certain facts go to show that radioactivity appertains in a slight degree to all kinds of matter. It may be, therefore,
that matter is far from being as unchangeable or inert as it was formerly thought; and is, on the contrary, in continual transformation, although this transformation escapes our notice by its relative slowness."
Madame Curie, Modern Theories
of
Electricity
and
Matter (Annual Report, Smithsonian Institution, 1905-1906, pages 103-104).
A remarkable summary of recent advances in physical science, by Sir Joseph Thomson, in his presidential address at the opening (August 25, 1909) of the seventy-ninth annual meeting of the British Association for the Advancement of Science, held at Winnipeg, Canada, contains what is, without doubt, the most successful of endeavors to give some understanding of the new conceptions of matter, ether and electricity, with which scientists are now working, to minds that have not been scientifically trained. Sir Joseph treats the subject at more length than can be given to it here, but abridgment seems possible without robbing it of the more important parts of its rich content of information:
"The period which has elapsed since the Association last met in Canada [1897] has been," said the President, "one of almost unparalleled activity in many branches of physics, and many new and unsuspected properties of matter and electricity have been discovered. The history of this period affords a remarkable illustration of the effect which may be produced by a single discovery; for it is, I think, to the discovery of the Röntgen rays that we owe the rapidity of the progress which has recently been made in physics. A striking discovery like that of the Röntgen rays acts much like the discovery of gold in a sparsely populated country; it attracts workers who come in the first place for the gold, but who may find that the country has other products, other charms, perhaps even more valuable than the gold itself. The country in which the
gold was discovered in the case of the Röntgen rays was the department of physics dealing with the discharge of electricity through gases, a subject which, almost from the beginning of electrical science, had attracted a few enthusiastic workers, who felt convinced that the key to unlock the secret of electricity was to be found in a vacuum tube.
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Röntgen, in 1895, showed that when electricity passed through such a tube the tube emitted rays which could pass through bodies opaque to ordinary light; which could, for example, pass through the flesh of the body and throw a shadow of the bones on a suitable screen. … It is not, however, to the power of probing dark places, important though this is, that the influence of Röntgen rays on the progress of science has mainly been due; it is rather because these rays make gases, and, indeed, solids and liquids, through which they pass, conductors of electricity. … The study of gases exposed to Röntgen rays has revealed in such gases the presence of particles charged with electricity; some of these particles are charged with positive, others with negative, electricity. The properties of these particles have been investigated; we know the charge they carry, the speed with which they move under an electric force, the rate at which the oppositely charged ones recombine, and these investigations have thrown a new light, not only on electricity, but also on the structure of matter. We know from these investigations that electricity, like matter, is molecular in structure, that just as a quantity of hydrogen is a collection of an immense number of small particles called molecules, so a charge of electricity is made up of a great number of small charges, each of a perfectly definite and known amount. … Nay, further, the molecular theory of matter is indebted to the molecular theory of electricity for the most accurate determination of its fundamental quantity, the number of molecules in any given quantity of an elementary substance.
"The great advantage of the electrical methods for the study of the properties of matter is due to the fact that whenever a particle is electrified it is very easily identified, whereas an uncharged molecule is most elusive; and it is only when these are present in immense numbers that we are able to detect them. …
"We have already made considerable progress in the task of discovering what the structure of electricity is. We have known for some time that of one kind of electricity the negative and a very interesting one it is. We know that negative electricity is made up of units all of which are of the same kind; that these units are exceedingly small compared with even the smallest atom. … The size of these corpuscles is on an altogether different scale from that of atoms; the Volume of a corpuscle bears to that of the atom about the same relation as that of a speck of dust to the Volume of this room. Under suitable conditions they move at enormous speeds, which approach in some instances the velocity of light. The discovery of these corpuscles is an interesting example of the way Nature responds to the demands made upon her by mathematicians. Some years before the discovery of corpuscles it had been shown by a mathematical investigation that the mass of a body must be increased by a charge of electricity. This increase, however, is greater for small bodies than for large ones, and even bodies as small as atoms are hopelessly too large to show any appreciable effect; thus the result seemed entirely academic. After a time corpuscles were discovered, and these are so much smaller than the atom that the increase in mass due to the charge becomes not merely appreciable, but so great that, as the experiments of Kaufmann and Bucherer have shown, the whole of the mass of the corpuscle arises from its charge.
"We know a great deal about negative electricity; what do we know about positive electricity? Is positive electricity molecular in structure? Is it made up into units, each unit
carrying a charge equal in magnitude though opposite in sign to that carried by a corpuscle? … The investigations made on the unit of positive electricity show that it is of quite a different kind from the unit of negative; the mass of the negative unit is exceedingly small compared with any atom; the only positive units that up to the present have been detected are quite comparable in mass with the mass of an atom of hydrogen; in fact they seem equal to it. This makes it more difficult to be certain that the unit of positive electricity has been isolated, for we have to be on our guard against its being a much smaller body attached to the hydrogen atoms which happen to be present in the vessel. … At present the smallest positive electrified particles of which we have direct experimental evidence have masses comparable with that of an atom of hydrogen.
"A knowledge of the mass and size of the two units of electricity, the positive and the negative, would give us the material for constructing what may be called a molecular theory of electricity, and would be a starting point for a theory of the structure of matter; for the most natural view to take, as a provisional hypothesis, is that matter is just a collection of positive and negative units of electricity, and that the forces which hold atoms and molecules together, the properties which differentiate one kind of matter from another, all have their origin in the electrical forces exerted by positive and negative units of electricity, grouped together in different ways in the atoms of the different elements. As it would seem that the units of positive and negative electricity are of very different sizes, we must regard matter as a mixture containing systems of very different types, one type corresponding to the small corpuscle, the other to the large positive unit. Since the energy associated with a given charge is greater the smaller the body on which the charge is concentrated, the energy stored up in the negative corpuscles will be far greater than that stored up by the positive. The amount of energy which is
stored up in ordinary matter in the form of the electrostatic potential energy of its corpuscles is, I think, not generally realized. … This energy is fortunately kept fast bound by the corpuscles; if at any time an appreciable fraction were to get free the earth would explode and become a gaseous nebula. The matter of which I have been speaking so far is the material which builds up the earth, the sun, and the stars, the matter studied by the chemist, and which he can represent by a formula; this matter occupies, however, but an insignificant fraction of the universe; it forms but minute islands in the great ocean of the ether, the substance with which the whole universe is filled.
{606}
"The ether is not a fantastic creation of the speculative philosopher; it is as essential to us as the air we breathe. For we must remember that we on this earth are not living on our own resources; we are dependent from minute to minute upon what we are getting from the sun, and the gifts of the sun are conveyed to us by the ether. It is to the sun that we owe not merely night and day, springtime and harvest, but it is the energy of the sun, stored up in coal, in waterfalls, in food, that practically does all the work of the world. … On the electro-magnetic theory of light, now universally accepted, the energy streaming to the earth travels through the ether in electric waves; thus practically the whole of the energy at our disposal has at one time or another been electrical energy. The ether must, then, be the seat of electrical and magnetic forces. We know, thanks to the genius of Clerk Maxwell, the founder and inspirer of modern electrical theory, the equations which express the relation between these forces, and although for some purposes these are all we require, yet they do not tell us very much about the nature of the ether.
"Let us consider some of the facts known about the ether. When light falls on a body and is absorbed by it, the body is
pushed forward in the direction in which the light is travelling, and if the body is free to move it is set in motion by the light. Now it is a fundamental principle of dynamics that when a body is set moving in a certain direction, or, to use the language of dynamics, acquires momentum in that direction, some other mass must lose the same amount of momentum; in other words, the amount of momentum in the universe is constant. Thus, when the body is pushed forward by the light, some other system must have lost the momentum the body acquires, and the only other system available is the wave of light falling on the body; hence we conclude that there must have been momentum in the wave in the direction in which it is travelling. Momentum, however, implies mass in motion. We conclude, then, that in the ether through which the wave is moving there is mass moving with the velocity of light. The experiments made on the pressure due to light enable us to calculate this mass. …
"The place where the density of the ether carried along by an electric field rises to its highest value is close to a corpuscle, for round the corpuscles are by far the strongest electric fields of which we have any knowledge. We know the mass of the corpuscle, we know from Kaufmann’s experiments that this arises entirely from the electric charge, and is therefore due to the ether carried along with the corpuscle by the lines of force attached to it. … Around the corpuscle ether must have an extravagant density; whether the density is as great as this in other places depends upon whether the ether is compressible or not. If it is compressible, then it may be condensed round the corpuscles, and there have an abnormally great density; if it is not compressible, then the density in free space cannot be less than the number I have just mentioned. With respect to this point we must remember that the forces acting on the ether close to the corpuscle are prodigious. … I do not know at present of any effect which would enable us to determine whether ether is compressible or not. And although at first sight the idea that we are immersed
in a medium almost infinitely denser than lead might seem inconceivable, it is not so if we remember that in all probability matter is composed mainly of holes. We may, in fact, regard matter as possessing a bird-cage kind of structure in which the Volume of the ether disturbed by the wires when the structure is moved is infinitesimal in comparison with the Volume enclosed by them. If we do this, no difficulty arises from the great density of the ether; all we have to do is to increase the distance between the wires in proportion as we increase the density of the ether."
Some English journals, in discussing Sir Joseph Thomson’s address at Winnipeg, spoke doubtingly of its scientific soundness, regarding it as too speculative, representing conclusions in advance of what physical science had obtained a real warrant to draw. These newspaper critics were called sharply to account by Sir Oliver Lodge, and told that they were suspicious of Sir Joseph’s statements only because they knew nothing of the data on which he founded them.
In a magazine article of the previous year, Sir Oliver Lodge had already traversed part of the ground covered by the impressive review of Sir Joseph Thomson. In that article he said of the present conception of the ether of space, as accepted among the leaders of physical science:
"When a steel spring is bent or distorted, what is it that is really strained? Not the atoms the atoms are only displaced; it is the connecting links that are strained the connecting medium the ether. Distortion of a spring is really distortion of the ether. All strain exists in the ether. Matter can only be moved. Contact does not exist between the atoms of matter as we know them; it is doubtful if a piece of matter ever touches another piece, any more than a comet touches the sun when it appears to rebound from it; but the atoms are connected, as the planets, the comets and the sun are connected, by a continuous plenum without break or
discontinuity of any kind. Matter acts on matter solely through the ether. But whether matter is a thing utterly distinct and separate from the ether, or whether it is a specifically modified portion of it modified in such a way as to be susceptible of locomotion, and yet continuous with all the rest of the ether, which can be said to extend everywhere, far beyond the bounds of the modified and tangible portion called matter are questions demanding, and I may say in process of receiving, answers.
"Every such answer involves some view of the universal, and possibly infinite, uniform, omnipresent connecting medium, the ether of space."
Oliver Lodge, The Ether of Space (North American Review, May, 1908).
[Transcriber's Note: The Michelson-Morley experiment 21 years earlier had cast doubt on the ether concept. https://www.gutenberg.org/ebooks/70888]
SCIENCE AND INVENTION, RECENT: Radium and Radio-activity: The Discovery by Professor and Madame Curie. The Light it throws on many Scientific Problems. Faraday’s Prophetic Anticipation. The Dissolution of Atoms.
"In his first treatise on the X-rays, Röntgen [see in Volume VI.] drew attention to the fact that they proceeded from those parts of the Röntgen tubes where the glass, under the influence of the impinging cathode rays, showed the most fluorescence. It therefore seemed possible that the existence of these mysterious rays was in some way dependent on previously acquired fluorescence, and many physicists tried to ascertain with the well-known Balmain dyes, which become luminous after exposure to the light, if results could be
obtained resembling those with a Röntgen tube.
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"Similar attempts by the French physicist, Henri Becquerel, were crowned with success in an unexpected direction. He exposed a uranium salt to the light, and then placing it in a dark room on a photographic plate covered with opaque paper he demonstrated the action of these rays on the plate through the paper, thin sheets of metal, etc. But the supposed and sought-for relation of the rays to the previous fluorescence was not evident, for Becquerel obtained precisely the same results with preparations of uranium which had not only not been previously exposed directly to the light, but had purposely been kept some time in darkness and could therefore display no stored-up luminescence. He had, however, discovered the uranium or Becquerel rays. …
"At Becquerel’s suggestion Madame Curie undertook a systematic investigation of all the chemical elements and established the fact that with none of them, excepting uranium and thorium, could an appreciable effect indicating rays be obtained with her apparatus. On the other hand, she found that many of the minerals investigated showed noticeable action in this direction. The fact that a few of them, the uranium pitchblende, for example, from Joachimsthal, Bohemia, emitted rays three or four times stronger than those of pure uranium, and which could not therefore be announced as uranium rays, led her to suppose that in the pitchblende itself, apart from the uranium, there must exist a still more powerful radioactive substance. It is a matter of record how, in this research, which might serve as a model for such work, she and her husband, so soon afterwards to lose his life by a deplorable accident, succeeded in tracing this supposed substance more and more accurately, and finally in obtaining it pure. Madame Curie thus became the discoverer of radium, a new element possessed of wonderful, of fabulous qualities.
"Besides Madame Curie no other investigator but Professor Braunschweig, so far as I know, has yet succeeded in obtaining pure radium."
Franz Himstedt, Radioactivity (Annual Report, Smithsonian Institution, 1905-1906, pages 117-118).
"The phenomena of radio-activity revive interest in the prophetic views of Michael Faraday. In 1816, when he was but twenty-four years of age, he delivered a lecture at the Royal Institution in London on Radiant Matter. In the course of his remarks there occurs this passage: ‘If we now conceive a change as far beyond vaporization as that is above fluidity, and then take into account the proportional increased extent of alteration as the changes arise, we shall perhaps, if we can form any conception at all, not fall short of radiant matter; and as in the last conversion many qualities were lost, so here also many more would disappear. It was the opinion of Newton, and of many other distinguished philosophers, that this conversion was possible, and continually going on in the processes of nature, and they found that the idea would bear without injury the applications of mathematical reasoning as regards heat, for instance. If assumed, we must also assume the simplicity of matter; for it would follow that all the variety of substances with which we are acquainted could be converted into one of three kinds of radiant matter; which again may differ from each other only in the size of their particles or their form. The properties of known bodies would then be supposed to arise from the varied arrangements of their ultimate atoms, and belong to substances only as long as their compound nature existed; and thus variety of matter and variety of properties would be found co-essential.’"
George Iles,
Inventors at Work, pages 204-205 (Doubleday, Page & Co., New York).
"An ascertained commercial value of £4 per milligramme (equivalent to £114,000 per ounce) has been placed upon radium by a contract just entered into between the British Metalliferous Mines (Limited) and Lord Iveagh and Sir Ernest Cassel for the supply of 7½ grammes (rather more than a quarter of an ounce) of pure radium bromide. This very large order for radium will be supplied from the above named company’s mine near Grampound Road in Cornwall."
London Times, June 21, 1909.
SCIENCE AND INVENTION, RECENT:
The Mono-Rail Gyroscopic System.
A mechanical invention not yet developed, but which seems more than likely to count among the most important of the next few years, is that known as the Brennan mono-rail system, which balances cars and trains of cars on a single rail by use of the principle of the gyroscope. It was first exhibited by its English inventor, Mr. Louis Brennan, in model form, before the Royal Society, in 1907, and won so much confidence in its possibilities that the British War Office and the India Office gave financial assistance to meet the cost of the long experiments that were necessary for adapting the system to service on a large practical scale. The result of these experiments was exhibited in public trials at New Brompton, England, and, subsequently, at New York, in the later part of 1909. The following account of the exhibition at New Brompton was given by The Times:
"The car with which the test runs were carried out is 40 ft. in length and 10 ft. in width; its weight is 22 tons, and it is designed for a load of 10 to 15 tons. The weight of the gyroscopes, of which there are two, is 1½ tons, each having a
diameter of 3 ft. 6 in. The speed of rotation is 3,000 r. p. m., or considerably less than it was in the 6 ft. model exhibited before the Royal Society. It would be possible for the car to obtain the necessary power by collecting current from an overhead wire with a consequent saving of weight, but in the present example the motive power is provided by two Wolseley petrol engines, one of 80 h. p., and the other of 20 h. p., driving two direct-current shunt-wound motors of the Siemens type. It is not necessary that the car should be propelled electrically, and steam or other motive power could be employed; but in any case it would be necessary to spin the gyroscopes electrically, this method being ideal for the purpose. The air is exhausted from the gyroscope cases, the pressure in them being equivalent to from ½ in. to 5/8 in. of mercury. It is hoped in future installations to design the gyroscopes for higher speeds, and in that case it would be possible to reduce the size and weight of the equipment. In this first car the gyroscopes run in the vertical plane, but that is merely for convenience, the essential feature being that the trunnions should be at right angles to the track. …
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"Several experimental trips were made on the factory circular track as well as on the straight, and the car travelled with remarkable steadiness throughout. It is not likely that the Brennan mono-rail will find any wide field of application in this country, but there would appear to be great advantages in the system for mountain railways in India and elsewhere, and, indeed, it seems suitable for adoption in any country where new railways are being planned. The inventor lays stress on the absolute safety of the system at speeds ranging up to about 150 miles per hour."
SCIENCE AND INVENTION, RECENT: Sanitary.
See (in this Volume) PUBLIC HEALTH.
SCIENCE AND INVENTION, RECENT: Submarine Signal Bells.
In May, 1909, it was announced from Washington that "the Government, recognizing the substantial service rendered to shipping by submarine bells, has decided to extend their installation from time to time to light vessels and stations on both coasts and upon the great lakes. At present forty-six of the light vessels are thus equipped, and the signals which they send out are of undoubted aid to deep-water navigation. Canada, England, Germany, Holland, France, Sweden, and Denmark are following suit. The bells operate during fogs and at night and the sound waves emitted by the bell under water have been known to travel as far as twenty-seven miles. These sound waves are picked up by the receiving microphones on board ships, and by the code signal of each station the vessel’s navigator is able to tell where he is."
See (in this Volume) above, ELECTRICAL: WIRELESS TELEGRAPHY: THE CRY THAT BROUGHT HELP.
SCIENCE AND INVENTION, RECENT: The Turbine Steam Engine. Its Successful Development. First Use on Ocean Steamers. The "Lusitania" and "Mauretania."
"For a long time and well into the nineteenth century, water was lifted by pistons moving in cylindrical pumps. Meantime the turbine grew steadily in favor as a water motor, arriving at last at high efficiency. This gave designers a hint to reverse the turbine and use it as a water lifter or pump: this machine, duly built, with a continuous instead of an
intermittent motion, showed much better results than the old-fashioned pump. The turbine-pump is accordingly adopted for many large waterworks, deep mines and similar installations. This advance from to-and-fro to rotary action extended irresistibly to steam as a motive power. It was clear that if steam could be employed in a turbine somewhat as water is, much of the complexity and loss inherent in reciprocating engines would be brushed aside. A pioneer inventor in this field was Gustave Patrich De Laval, of Stockholm, who constructed his first steam turbine along the familiar lines of the Barker mill. Steam is so light that for its utmost utilization as a jet a velocity of about 2,000 feet a second is required, a rate which no material is strong enough to allow. De Laval by using the most tenacious metal for his turbines is able to give their swiftest parts a speed of as much as 1400 feet a second. His apparatus is cheap, simple and efficient; it is limited to about 300 horse-power. Its chief feature is its divergent nozzle, which permits the outflowing steam to expand fully with all the effect realized in a steam cylinder provided with expansion valve gear. Another device of De Laval which makes his turbine a safe and desirable prime mover is the flexible shaft which has a little, self-righting play under the extreme pace of its rotation.
"Of direct action turbines the De Laval is the chief; of compound turbines, in which the steam is expanded in successive stages, the first and most widely adopted was invented by the Honourable Charles A. Parsons of Newcastle-on-Tyne. … In 1894 Mr. Parsons launched his Turbinia, the first steamer to be driven by a turbine. Her record was so gratifying that a succession of vessels, similarly equipped, were year by year built for excursion lines, for transit across the British Channel, for the British Royal Navy, and for mercantile marine service. The thirty-fifth of these ships, the Victorian of the Allan Line, was the first to cross the Atlantic Ocean, arriving at Halifax, Nova Scotia, April 18, 1905. She was followed by the
Virginian of the same line which arrived at Quebec, May 8, 1905. Not long afterward the Cunard Company sent from Liverpool to New York the Carmania equipped with steam turbines, and in every other respect like the Caronia of the same owners, which is driven by reciprocating engines of the best model. Thus far the comparison between these two ships is in favor of the Carmania. The new monster Cunarders, the Lusitania and the Mauretania, each of 70,000 horse power, are to be propelled by steam turbines. The principal reasons for this preference are thus given by Professor Carl C. Thomas: Decreased cost of operation as regards fuel, labor, oil, and repairs. Vibration due to machinery is avoided. Less weight of machinery and coal to be carried, resulting in greater speed. Greater simplicity of machinery in construction and operation, causing less liability to accident and breakdown. Smaller and more deeply immersed propellers, decreasing the tendency of the machinery to race in rough weather. Lower centre of gravity of the machinery as a whole, and increased headroom above the machinery. According to recent reports, decreased first cost of machinery."
George Iles, Inventors at Work, pages 452-456 (Doubleday, Page & Co., New York).
In August, 1908, the Lusitania made the voyage from Queenstown to New York in 4 days and 15 hours; again in February, 1909, in 4 days, 17 hours and 6 minutes. In September, 1909, the
Mauretania crossed from New York to Queenstown in 4 days, 13 hours and 41 minutes.
SCIENCE AND INVENTION, RECENT:
The Washington Memorial Institution. Extension of the Usefulness of Scientific Work in Departments of the Government.
See (in this Volume) EDUCATION: UNITED STATES: A. D. 1901.
SCIENCE AND INVENTION, RECENT: The Nobel Prizes.
See (in this Volume) NOBEL PRIZES.
See also EARTHQUAKES.
----------SCIENCE AND INVENTION, RECENT: End--------
----------SCOTLAND: Start--------
SCOTLAND: A. D. 1901 (March). Census.
According to the returns of the decennial enumeration made on the night of the 31st of March, 1901, the population of Scotland that day, "including those in the Royal Navy, and belonging to the Mercantile shipping in Scottish Ports or on Scottish waters, number 4,472,000 persons, of whom 2,173,151 are males, and 2,298,849 females.
"When compared with the corresponding population as enumerated at the Census of 1891, a total increase of 446,353 is found to have occurred; the male increase being 230,434, and the female
215,919.
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The percentage rate of increase of both sexes during the decennial period is 11.09 that of the males being 11.86, and of the females 10.37. The corresponding total rate of increase during the preceding decennium, 1881-1891, was 7.77 per cent.
… The rate at the present Census for Scotland is, with the exception of that at 1881, the highest since the decennial period 1821-1831. …
"In 19 Counties an increase in the population has taken place, in 14 a decrease. The highest rate of increase both sexes combined is in Linlithgow, 24.4 per cent.; followed by Lanark with an increase of 21.1 per cent.; Stirling with one of 20.6 per cent.; Renfrew with one of 16.5 per cent.; Dumbarton with one of 16.2 per cent.; Kincardine with one of 15.3 per cent.; Fife with one of 15.0 per cent. The greatest falling off occurs in Berwick, 4.6 per cent.; in Orkney, 5.7 per cent.; in Roxburgh, 8.8 per cent.; in Caithness 8.9 per cent.; in Wigtown, 9.4 per cent.; and in Selkirk 15.8 percent. Inverness stands almost as it was, having increased but 0.1 per cent., and the minimum rate of falling off as to population is in Banff, 0.3 per cent., and Argyll, 0.6 per cent. …
"Among the larger Burghs the increase of population varies not a little. Thus, in Motherwell, which heads the list, the increase during the decennial period 1891-1901, is at the rate of 62.5 per cent. Partick follows with a rate of increase of 48.6 per cent.; Wishaw with one of 36.8 percent.; Hamilton with one of 31.8 per cent.; Kirkcaldy with one of 25.5 percent.; Falkirk with one of 24.3 per cent.; Govan with one of 24.2 per cent.; Coatbridge with one of 21.3 per cent.; Aberdeen with one of 22.9 per cent.; Kilmarnock with one of 20.1 per cent.; Paisley with one of 19.5 per cent.; Airdrie with one of 16.5 per cent.; Glasgow with one of 15.5 per cent.; Ayr with one of 15.1 per cent.; Edinburgh with one of 14.8 per cent.; Dunfermline with one of 14.1 percent.; Leith
