William Arnold Anthony

“ But, while the theory of thermodynamics asserts that the combustion of a pound of carbon yields an amount of heat equivalent to 11,116,800 foot-pounds of energy, it also asserts just as clearly and just as firmly that, under the conditions which exist upon this planet, heat can not be transformed into mechanical effect without wasting a considerable portion of the energy due to it. ”

“ By its aid we may frequently modify some of the conditions, known to be conditions, in such ways that the phenomenon is not arrested, but so altered in the rate with which its details pass before us that they may be easily observed. Experiment also often leads to new phenomena, and to a knowledge of activities before unobserved. Indeed, by far the greater part of our knowledge of natural phenomena has been acquired by means of experiment. To be of value, experiments must be conducted with system, and so as to trace out the whole course of the phenomenon. ”

“ It may be well to emphasize a little the first conclusion, that no heat-engine whatever can be more efficient than a reversible engine. If the reasoning is correct, no form of heat-engine, whether using air, or gas, or a condensable vapor, or a liquid, or a solid, as the working substance, or using thermo-electric currents, or any other means of converting heat into mechanical effect, can be more efficient than any one of the reversible engines. ”

“ We are almost constantly obliged, in physical science, to measure the quantities with which we deal. We measure a quantity when we compare it with some standard of the same kind. A simple number expresses the result of the comparison.
If we adopt arbitrary units of length, time, and mass (or quantity of matter) , we can express the measure of all other quantities in terms of these so-called fundamental units. A unit of any other quantity, thus expressed, is called a derived unit. ”

“ Why may not the union of carbon with oxygen be made to generate electric currents instead of heat? Electric energies have been made that convert into mechanical effect 60 to 70 per cent, of the energy of the electric current, and a much higher efficiency might, no doubt, be obtained. Already something has been done toward the generation of electric currents by the union of carbon and oxygen; but, so far, no means has been discovered by which such a union can be effected, except at a high temperature, and this involves a great waste of energy in the form of heat. ”

“ Measurements.—All the phenomena of Nature occur in matter, and are presented to us in time and space. Time and space are fundamental conceptions: they do not admit of definition. Matter is equally indefinable: its distinctive characteristic is its persistence in whatever state of rest or motion it may happen to have, and the resistance which it offers to any attempt to change that state. ”

“ No matter what the working substance, or in what way heat is made to yield mechanical effect, so long as the process is completely reversible, the same amount of mechanical effect will always be derived from the same heat taken from the source. ”

“ Those bodies which exhibit electrolysis are always such as have considerable freedom of motion among their molecules. Ordinarily, they are liquids or solids in solution or fused. The discharge through gases is also probably accompanied by electrolysis. Bodies which can be decomposed were called by Faraday, to whom the nomenclature of this subject is due, electrolytes. The current is usually introduced into the electrolyte by solid terminals called electrodes. The one at the higher potential is called the positive electrode or anode; the other, the negative electrode, or cathode. ”

“ A discovery that would enable us to convert the energy of fuel into electric currents directly and completely would revolutionize, not only the methods of obtaining power, but the methods of obtaining light and distributing heat as well. I have shown elsewhere that, if a Brayton oil-engine is used to drive a dynamo-electric machine producing the electric light, more than twice as much light will be developed as would be obtained if the oil that runs the engine were burned in the ordinary coal-oil lamps. ”

“ There is no escaping this conclusion except through the perpetual motion, or the derivation of mechanical effect from the heat of a body already cold. It has been sometimes claimed that the latter alternative was no impossibility, that the expansion of a compressed gas, the expansion of a gas into a vacuum, or the diffusion of one gas into another, may perform work at the expense of its own heat, while being cooled down to a lower temperature than surrounding bodies. ”

“ In conducting our experiments, and in reasoning upon them, we are often guided by suppositions suggested by previous experience. If the course of our experiment be in accordance with our supposition, there is, so far, a presumption in its favor. So, too, in reference to our reasonings: if all our facts are seen to be consistent with some supposition not unlikely in itself, we say it thereby becomes probable. ”

“ If a scale of temperature be constructed such that the temperature of the source is to the temperature of the refrigerator of a reversible engine as the heat derived from the source is to the heat given to the refrigerator, the scale divisions will differ but little from the divisions of the scales in common use. ”

“ The secondary cell of Planté is an example of a cell made directly by electrolysis, as has been assumed in the preliminary discussion. The electrodes are both lead plates, and the electrolyte dilute sulphuric acid. When a current is passed through the cell, the oxygen evolved on the anode combines with the lead to form peroxide of lead, which coats the surface of the electrode. When the cell is inserted in a circuit, a current is set up, the peroxide is reduced to a lower oxide, and the metallic lead of the other plate is oxidized. ”

“ In other words, if a given quantity of heat be taken from a source, as a steam-boiler, and made to do work by means of any form of engine, a considerable portion of that heat must, from the very nature of things under existing conditions, be allowed to pass through the engine and raise the temperature of other bodies to no useful purpose. ”

“ Measure of the Counter Electromotive Force of Decomposition.— In the general formula developed in § 377 the quantity represents the energy expended in the circuit which does not appear as heat developed in accordance with Joule's law. In the present case it is the energy expended during electrolysis in decomposing chemical compounds and in doing mechanical work. In many cases the mechanical work done is not appreciable; but when a liquid like water is decomposed into its constituent gases, work is done by the expansion of the gases from their volume as water to their volume as gases. ”

“ That the perpetual motion is impossible, and that "it is impossible by means of inanimate material agency to derive mechanical effect from any portion of matter by cooling it below the temperature of the coldest of surrounding objects." ”

“ Physics deals with all those phenomena of matter which are not directly related to chemical changes. Astronomy is thus a branch of Physics, yet it is usually excluded from works like the present on account of its special character. ”

“ Transfer of Heat.—In the preceding discussions it has been assumed that heat may be transferred from one body to another, and that if two bodies in contact be at different temperatures, heat will be transferred from the hotter to the colder body. In general, if transfer of heat be possible in any system, heat will pass from the hotter to the colder parts of the system, and the temperature of the system will tend to become uniform. ”

“ If A transfers to the refrigerator less heat than B takes away, the refrigerator will grow colder and colder, and, since for the purposes of this discussion all other bodies may be assumed to be at the same temperature as the source, this will present the case of a machine producing mechanical effect while taking heat from the coldest of surrounding bodies. ”

“ The Spark, Brush, and Glow Discharges.—When a conductor is charged to a high potential and brought near another conductor which is joined to ground, a spark or a series of sparks will pass from one to the other. This phenomenon and others associated with it are most readily studied by the use of an electrical machine or an induction coil, between the electrodes of which a great difference of potential can be easily produced. ”

“ The piston and sides of the cylinder are supposed to be perfect non-conductors, while the bottom of the cylinder is a perfect conductor of heat. The engine has a source of heat and a refrigerator, whose temperatures are supposed to remain absolutely constant whether parting with or receiving heat. There is also a non-conducting stand, on which, if the cylinder be placed, no heat can enter or escape from it, however much the air within it may change in temperature. ”

“ If a current be sent through the series of cells containing these solutions, the same number of univalent, ions will be liberated in each. The difference of potential between the terminals of the cells will be in general different for each of them. We have from Ohm's law the relation where the current is the same for each cell and the difference of potential and the conductivity (§ 275) different for the different cells. Now consider a cross-section in one of the cells parallel with the electrodes; let and represent the velocities of the ions evolved in this cell. ”

“ That all reversible engines, whatever the working substance, have the same efficiency; that is, taking from the source the same quantity of heat H, they will transfer to the refrigerator the same quantity h, and convert into mechanical effect the same quantity Hh. Hence whatever results are derived from a discussion of any one form of reversible engine will be true of all others. ”

“ Divisions of Natural Science.—Everything which can affect our senses we call matter. Any limited portion of matter, however great or small, is called a body. All bodies, together with their unceasing changes, constitute Nature. ”

“ It is that of an engine completely reversible in all its physical and mechanical agencies. A water-motor which could be driven backward by means of some source of power, and would then raise to a given level as much water as it would use from that level to develop the power required to run it backward, would be a reversible engine. It is plainly to be seen that such a motor would be a perfect motor, and also a perfect pump. ”

“ Concerning the ultimate modes of existence or action, we know nothing whatever; hence, a law of nature cannot be demonstrated in the sense that a mathematical truth is demonstrated. Yet so great is the constancy of uniform sequence with which phenomena occur in accordance with the laws which we discover, that we have no doubt respecting their validity. ”

“ A reversible heat-engine would be one which, running forward and performing a certain amount of work by means of a given amount of heat derived from a source, would, if run backward by the performance upon it of the same amount of work, restore to the source the same amount of heat. ”

“ The body of the tube is filled with a faint rosy light, which in many cases breaks up into a succession of bright and dark layers transverse to the direction of the discharge. The discharge in this case is called the stratified discharge. A vacuum-tube m which the exhaustion is such that the phenomena are those here described is often called a Geissler tube. As the exhaustion is raised still higher, the rosy light in the tube fades out, the non-luminous space around the negative electrode becomes very much greater, and the phenomena in the tube become exceedingly interesting. ”

“ Such a heat-engine would be a perfect engine in the sense that it would produce as much mechanical effect as could be produced by any heat-engine under the same conditions from the same quantity of heat. ”

“ Let represent the weight of the hydrogen evolved by unit current in unit time, and the chemical equivalent of one of the products of electrolysis in the cell. Then represents the weight of that product evolved by unit current in unit time, and represents the current that will evolve unit weight in unit time. Now the electrolytes are prepared so that the weights of the constituents in the cells are given by where is a number which is the same for all the cells. ”

“ Two platinum electrodes are immersed in water slightly acidulated with sulphuric acid, and tubes are arranged above them so that the gases evolved can be collected separately. When the current is passing, bubbles of gas appear on the electrodes. When they are collected and examined, the gas which appears at the anode is found to be oxygen, and that which appears at the cathode to be hydrogen. The quantities evolved are in the proportion to form water. ”

“ The Electric Arc.—If the terminals of an electric circuit, in which is an electromotive force of forty or more volts, be formed of carbon rods, a brilliant and permanent luminous are will appear between the ends of the rods if they be touched together and then withdrawn a short distance from each other. ”

“ The process of reasoning by which we discover such laws is called induction. As we can seldom be sure that we have apprehended all the related facts, it is clear that our inductions must generally be incomplete. ”

“ The discharge seems to be independent of the position of the positive electrode, and to take place in nearly straight lines, which start normally from the negative electrode. If two negative electrodes be fixed in the tube, the discharge from one seems to be deflected by the other, and two discharges which meet at right angles seem to deflect one another.
If the discharge from a flat electrode be made to fall upon a body which can be moved, such as a glass film, or the vane of a light wheel, mechanical motions will be set up. ”