WHATEVER may be said as to the limitations of college curricula, no conception of a university is complete which does not include some representation of all the great departments of mental activity, whether this activity is expended upon material or psychical phenomena. Indeed, if its name mean anything, the university is, potentially, to systematize all knowledge, and to group separate intellectual energies into well-considered orders. The special investigator may be pursuing his studies without any thought of the relation which they hold to other studies, and, under the impulse of a common interest, a great many experiments may be making on parallel lines, which await the correlating thought of some generalizing mind. It is the business of the university to take account of such movements, and, by the very classification which it makes, to direct attention to the order into which certain studies fall. If it be the function of such scientists as Fourier, Clausius, Faraday, Helmholtz, Sir William Thomson, Clerk-Maxwell, and Joseph Henry to lay the foundations for such inventors as Watt, Fulton, Morse, William Thomson, Bell, and Edison, it is once more the function of men of science, collectively engaged in formulating the results thus reached and putting them into sysmatized form, to make them the intellectual property of new students.
The published literature of the past year shows how vigorously researches in mechanics, chemistry, electrics, thermoties, acoustics, and optics are being prosecuted by the aid both of mathematics and of experiment. An examination of the courses of study in our leading universities will show that these subjects hold a prominent place, and are provided for in laboratory work and class-room exercises. On the other hand, the literature of one great department of higher science shows but slow progress, and I see no indication that the universities recognize its importance, and are making preparation for its adequate presentation. No doubt the impetus to scientific study in the subjects mentioned above has been very forcible from the immediate pressure of material interest; science can scarcely help being absorbed in electricity when capital is seeking outlet. through electrical appliances; but though the university is bound to follow whither capital beckons, it owes a larger debt to those fields of research which concern vaster problems, but have not the attraction of immediate and visible material gain.
My plea, then, is for a recognition by our highest institutions of learning of the claims of terrestrial physics as a distinct department of research and of instruction. The problems specifically included under this term embrace all those in which we consider the land, the ocean, and the atmosphere, respectively, as units, or as parts of the greater unit which astronomers call “ the earth,”— problems in which the phenomena depend more or less upon the size, the shape, the diurnal rotation, and annual revolution of our globe, or upon the viscosity, the elasticity, the density, and the mutual attraction of its parts. The phenomena to be studied are often of entrancing beauty, and always of such importance as to justify one in spending time and labor upon their investigation.
Terrestrial physics is the Study of the globe upon which we live as distinguished from the study of the matter by which we live ; as the matter studied in molecular physics is a part of man, so man is a part of the globe. Man can alter the molecular conditions of food substances until he adapts them to the conditions of his own physiology, but he cannot alter the greater terrestrial conditions surrounding him. He may experiment with earth, and air, and water, hut not with the earth, the ocean, and the atmosphere ; these he may only study and understand so as to adapt himself to them. The establishment of observatories, laboratories, schools, and other institutions for the promotion of terrestrial physics will contribute directly to the advancement of civilization by just so far as they contribute to an increased knowledge of the environment of the human race.
The present condition of mathematical, astronomical, chemical, and molecular studies is traceable to the careful nurture of observatories and laboratories, and to the general instruction in these matters ; the patrons of these sciences are the sovereigns and universities of the nations of the world, But the number of those who have been free to devote themselves to either experimental or mathematical work in terrestrial physics is comparatively small, and their financial means still smaller relatively to the former class of workers. Could we see a corresponding attention given to the nurture of the latter, and a corresponding encouragment to students to devote themselves to this work, we should certainly see corresponding excellent results. But, not to stop at generalizations, let us glance particularly at some branches of our subject.
I. Vulcanology. The most difficult problems are those relating to the conditions of the interior of the earth, and the reaction of that on the surface. The growth of our knowledge of these questions was ably set forth at the Toronto meeting of the American Association for the Advancement of Science by Mr. R. S. Woodward, and his historical sketch affords a fine illustration of the attention given by astronomers to physical problems. But astronomy and pure mathematics will never alone settle these questions ; in the nature of things, they never can, and I propose that they be relegated to the conjunction of astronomers with experimental and mathematical physicists and chemists, and that means be provided for the study of terrestrial matter under high pressures and temperatures. It is possible — nay, probable — that the internal heat of the earth is not necessarily so excessive as was formerly supposed, and certainly the internal pressure is vastly greater than is generally realized.
The fluidity of the earth’s interior is due to pressure quite as much as to heat. Our globe is of the nature of a plastic and viscous mass, and this has sufficed to enable it to become spheroidal without the need of assuming that it was once a limpid fluid. Give it time enough, and it will slowly take any required shape; release the interior masses from heavy pressure, and they will become as rigid as we see them at the surface. The lava and trap disgorged from beneath the earth’s surface may have given a wrong impression as to the general state of the deepest interior regions; for they may come from moderate depths, and their heat and liquidity may be in great part the result of unknown chemical changes that slowly mature at moderate temperatures under enormous crushing pressures. We know little about the effect of such long-continued temperatures and pressures, because they are beyond the reach of our present experimental researches, but I understand that an earnest effort is being made in this line of work by our Geological Survey.
In common with others, I have for years hoped that observations of terrestrial magnetism would give us some idea as to the condition of the depths of the earth; but I shall show that we must give this up, so that we are forced to base our hopes upon experimental work on the chemical and physical behavior of solids under great pressure, and upon mathematical work on the laws of elasticity of a large non-homogeneous mass of viscous matter such as is our so-called globe. The experimental work may be considered as already begun; the foundations of the mathematical work known as the theory of elasticity in viscous solids have been laid by Clebsch and Saint Venant and their numerous followers.
II. Geognosy. From the deeper depths, hidden from touch or sight within the earth, we ascend to the surface, or crust, where a variety of important phenomena and problems present themselves. Have the general locations and features of the continents and the ocean beds always been as now ? What is the mechanism of the rise and fall of mountain chains, and the crumpling of strata that once were horizontal ? The phenomena we observe belong to geology, but their explanation belongs to geognosy, and is a matter for experimental mechanics and physics.
It has already become evident that the steady action of great pressure upon hard, solid rock will mould it like clay into all the forms that we have observed, if only time enough be given. There is nothing known that is absolutely rigid ; warmth, pressure, and time change all things. A ball of glass is highly elastic ; its molecules transmit the most rapid vibrations of the spectrum to give us light, while its mass, struck by a hammer, vibrates less rapidly with a clearsounding note to give us the slower vibrations of sound. But substitute a long-continued pressure for this quick blow, and the glass becomes as permanently deformed as does the plastic clay; it is elastic to quick blows, but plastic to very long continued pressures. The experimental study of the relations of pressure, temperature, and time, or the so-called “ flow of solids ” at ordinary temperatures, was begun recently, and is now carried on by many. The manufacture of lead pipes and spun pans, of gold medals or of cold-drawn wire, illustrates to every one what we mean by the flow of solids. The temperature and the plastic deformations of our earth’s crust demand careful study. The experimental researches in mountain building by H. M. Cadell, and the deep-bore temperatures by Dunker, are the latest contributions to these subjects, and much more of that kind of work remains to be done by special physical laboratories. Even the gas and oil wells and coal beds have their stories to tell in regard to their formation during the slow process of terrestrial crumpling. Why do we not study the problems ? Is it for want of money or for lack of opportunity ?
The origin of these great crumpling pressures has long been debated, but in my next section I shall maintain that we are not to attribute this crumpling and mountain building in recent geological ages altogether to pressures resulting from contraction, itself the result of the general cooling of the earth’s surface. This cooling is undoubtedly a true cause, and has afforded magnificent problems for Fourier and his followers ; but it has become a less important cause as compared with another one, the evidences of whose existence are now everywhere apparent.
III. Seismology. Our earth is subject to earthquakes : some of these are local ; others start with a shock, and spread as a vibration far and wide. What are these shocks ? In general, it seems to me, we must reply that the attractions of the sun and moon produce a system of strains within the earth. On the one hand, these strains cause a part or even the whole of the external crust sometimes to slide a little about its viscous interior ; on the other hand, these strains occasionally and systematically combine, so that the crust cracks and separates, or crumples and faults a little, and this operation is repeated accumulatively age after age, until mountain chains and continents are formed. The specific day when such cracks are most likely to occur is that when the sun and moon are in conjunction and in perigee. At that time we have the greatest tidal strains. This condition endures for a day or two as the moon moves past the sun. During each day, at this period of conjunction, the earth, by its rotation, presents each meridian successively to the sun and moon, and causes all its substance to pass through the region of greatest strain. Now, our globe is not strictly homogeneous as to density nor as to strength, and when its weakest great circle comes into the plane of greatest strain there is a slight give, an earthquake, a fault, a dislocation of strata, a squeezing up of lava. Thus it goes on, age after age. The steady process of crumpling is therefore caused by lateral pressures, that are due not so much to cooling as to the tidal strains in the solid but plastic globe itself.
The dependence of the earthquakes of the Pacific Ocean on the sun and moon is suggested by statistics. The great circle of the Andes, Rocky Mountains, and eastern Asia marks the principal plane of weakness of the earth’s crust: this divides the great depressions of the bed of the Pacific Ocean from the elevations of Europe, Asia, Africa, and America; or, it divides the land from the water hemispheres.
Doubtless in early ages our crust may have yielded more frequently than now to special strains produced at every conjunction or opposition of the sun and moon, but for a long time past the principal yieldings must have been those which occurred when sun and moon were in perigee; and in this way has been brought about that remarkable configuration throughout the world of mountain ranges and coast lines whose great circles are tangent to the Arctic and Antarctic circles. A very similar slower tidal strain in the body of the moon has given her surface a bulge and a series of ridges that are admirably prominent to the eye of the astronomer.
The pressure due to luni-solar tidal strain is a more potent factor and a more systematic agent in producing sliding and crumpling than that due to contraction by cooling. But the motions of the strata are liable to be spasmodic, and the earthquake shocks become earthquake vibrations that run over a large portion of the earth’s surface : the study of these vibrations may properly be expected to enable us to trace each to its origin, and thus show to us the depth to which the tidal strain is effective. Below this depth it is evident that a species of rock welding goes on ; the rocks, under great pressure and moderate heat, weld into one continuous plastic mass. This strata of welded rock is the extreme limit of the earth’s crust.
The new electric welding process offers special advantages for studying the exact temperatures and pressures (and therefore the exact depth of the earth) at which rock welding takes place. The study of earthquakes and vibrations is a fundamental problem for any institution that is devoted to terrestrial physics. I have for many years labored to stimulate the observation and active study of these phenomena, and hope that the United States, like Europe, will foster an interest therein.
IV. Nutation and Rotation. The earth’s axis of rotation coincides very closely with its axis of maximum inertia, namely, its shortest polar diameter or “ principal axis.” So long as these exactly coincide, our latitudes and longitudes will be constant; whatever causes either axis to differ will introduce slight periodic changes in latitudes and longitudes, due to the revolution of the instantaneous axis of rotation about the principal axis of inertia; and if the earth were a perfectly elastic mass, this periodic change would continue indefinitely. But, in so far as the earth is a truly homogeneous viscous mass, it will slowly accommodate its figure to the new conditions ; it will stretch a little with each rotation about the instantaneous axis of rotation, and will flatten out a little more at the poles, and finally settle down to permanently steady rotation around a new permanent or subpermanent axis of maximum inertia, situated between the two axes of rotation and of maximum inertia, with a new rate of rotation a little slower than before. Thus it happens that, principally, as it seems to me, through the action of the sun and moon, producing occasional geological and orographic changes in the crust of the earth, our latitudes have at present small periodic changes, dying away to a period of constancy or rest, followed by a new set of changes, and again a period of rest, while, on the whole, the day is slowly lengthening and the longitudes are diminishing, all of which would not occur were the earth perfectly elastic or perfectly rigid. This process will continue until our equatorial bulge is as large as the sun’s and the moon’s attractions combined with the earth’s centrifugal force are any way able to maintain. Our globe may not be old enough to have as yet attained its maximum bulge. In former ages, the globe may have been, more emphatically than now, a nonhomogeneous viscous mass ; and then, as shown by Schiaparelli, much larger periodic changes of latitude may have occurred, due to the sliding of the exterior crust over the interior softer mass.
The astronomers were the first to suspect the existence of these movements of the earth’s crust, and their reality is now beginning to he acknowledged; it remains for the physicist and the student of elasticity to show the meaning of the changes that trouble the delicate measurements of astronomy and geodesy, and to deduce the general average coefficient of viscosity of our globe. We may even be able to elucidate the process of disintegration by which, apparently, Saturn’s rings were formed.
V. Gravitation. The attraction of the earth as a whole for other objects has long been a favorite subject of observation and study. The time of vibration of the ordinary pendulum gives us the means of measuring the relative force of gravity at different points. Simpler instrumental means are desirable, and the physicist must supply them if he can. In the pendulum, gravity is opposed to the inertia of the mass of the pendulum. In the spring balance, gravity is opposed to the elasticity (or, more precisely, to the inertia of the molecules) of the metallic spring, whose temperature is far above that absolute zero where there can be no elasticity. In the horizontal pendulum and the torsion balance, we have the means of measuring attractions by methods parallel in principle to the two preceding respectively. A fine series of determinations of gravity, such as those made for the Coast Survey by Mr. E. D. Preston during the recent expedition under Professor D. P. Todd, is an important contribution to the general question of the attraction of islands and oceans relatively to the whole earth. But a minute pendulum survey of the territory of the United States, especially of the mountain chains, is now very desirable. Every one will recognize that such determinations of gravity form an important branch of terrestrial physics. Will not some one devise a sufficiently delicate form of spring balance, some adaptation of Michelson’s refractometer, to replace the laborious pendulum ?
VI. Terrestrial Magnetism. There is no more mysterious yet practically useful force than the so-called terrestrial magnetism. Strange that we should know so little about that which is daily manifest to us. When we handle a bar of magnetic iron, we know that, although we do not understand what magnetism is, at least we can say that it exists within this bar. Now, the earth acts like a great magnet, yet we dare not say it is a magnet; we even hesitate to reason upon the general hypothesis that Gauss assumed in his Theoria, which is that it has magnetic matter distributed irregularly throughout it. The fact is, the recent work on “ recalcescence ” shows that at a temperature of 690° Centigrade iron and steel cease to be magnetic. Now, that temperature must be attained at a depth of 27,500 metres, if the earth’s temperature goes on increasing downward at the rate of 25° C. per thousand metres, as found by Dunker at the bore at Sperenberg; or at the depth of 25,500 metres, if the rate of increase is 27° C., as found by him at Schladebach. Therefore all magnetized iron must be within a thin outer crust that is scarcely twelve miles deep. But Gauss showed that the average magnetism at the surface of the globe corresponds to the distribution throughout its whole interior of seven one-pound steel magnets per cubic metre. If this magnetic force is to be all confined to such an outer thin crust, then the average magnetic charge of its mass must be one hundred times greater per cubic metre. But this is preposterous, and we must conclude either that the interior of the earth has not this high temperature, or else that the material of the earth is not truly magnetic ; no more so, that is, than is the copper wire which conducts a current around an electro-magnet, and which coil in fact has all the properties of a magnet without being one. The latter alternative we can easily adopt, but we have still to demonstrate the origin of the electric current that circulates around the globe and makes it an electro-magnet.
The observers and students of terrestrial magnetism are numerous, but Nature still holds fast her secret; and in this field of investigation we especially need the best talent in mathematical and experimental physics. I may, however, indicate the fact that, apparently, one feature of the subject has been unriddled, namely, the systematic diurnal, annual, and twenty-six-day perturbations, and also the irregular storms. This is the work of Professor Bigelow, of Washington, who has published a synopsis of his recent studies in a bulletin of the Eclipse expedition to the West Coast of Africa. He finds these perturbations fully explained qualitatively, and we hope quantitatively also, by considering the action of a conducting globe within a less perfectly conducting atmospheric envelope, rotating diurnally and revolving annually in a field of electric force such as must proceed from the sun concurrently with that other influence that gives us light and heat as its effects on our senses.
Thus much for the perturbations, but the main phenomenon, the sub-permanent magnetism, is still unsolved, though I think the most plausible view is that the tidal strains that we have already had to consider produce a steady supply of piezo-electricity, that manifests itself in ground currents, the flow of which is mainly east to west, and converts our earth into an electro-magnet. This conclusion forced itself upon me in 1888 or early in 1889, but now seems to have been long since arrived at by no less an authority than Clerk-Maxwell, whom I most unexpectedly find to have suggested it in the second volume of his Treatise on Electricity.
VII. Oceanography. The relation between the ocean and the land, as well as the special phenomena of the ocean itself, offers a new series of problems to be studied, of which we would especially mention those relating to tides and currents and deep-sea temperatures. The researches of the Challenger expedition, and those of our own Coast Survey and navy, have opened to wondering eyes an unknown world in the depths of the sea.
The average temperature of the ocean bottom is but a little more constant than the average temperature of the surface of the land ; therefore, so far as the conduction of heat is concerned, the interior of the earth gives up no more annually to the sea than it does to the atmosphere, namely, sufficient to melt one fourth inch of ice per annum; therefore, the ocean beds have not been formed by special cooling processes. The theory of contraction by cooling fails to account for the great watery hemisphere of our globe, with its centre at the antipodes of London. This great deformation is undoubtedly the work of those insidious lunar and solar tidal strains above alluded to ; and the same mathematical analysis that, in the hands of Darwin, deals with these strains has, in the hands of Rayleigh, dealt with the tides of the great watery oceans. The ocean and the earth beneath it differ only in quality, not in kind : they are both viscous, yielding masses.
From the study of the great tidal waves we may pass to that of the long earthquake waves that cross the Atlantic and the Pacific, and then to that of the great storm waves, and finally to the study of the short swell of the ocean: each of these classes of waves offers an important field of study ; probably no more magnificent illustration of the interference of waves can be found than is shown in the phenomenon of the “rollers ” and “ double rollers ” of the islands of Ascension and Saint Helena. The recent Eclipse expedition afforded me an admirable, almost unique opportunity to perceive the nature of this dreaded phenomenon, in that, from a high hill, I found myself looking down upon a wide expanse of ocean covered with intersecting systems of waves. Such problems as these on ocean waves cannot easily be studied in a permanent institution, but the experimental results obtained there should be verified by sending the experimenters to observe at the localities where they are best developed.
VIII. Meteorology. Our atmosphere is a part of our earth. It is included in its mass when the astronomer speaks of the mutual attraction of the earth, the sun, and the moon ; it is the most important factor in our geological history ; it is also the most important factor in the existence of man, — he may live forty days without food, but not forty minutes without fresh air. The phenomena of the atmosphere generally take place on too large a scale to be called local. A large region of the atmosphere is affected by every storm. The winds carry the seeds of plants and germs of disease from one continent to another. The droughts and floods, the heat and cold, of America depend on what is doing in Asia and the tropics. There can be no proper study of meteorology except as one includes the whole globe in his thoughts.
The past thirty years have seen the establishment in every civilized country of weather bureaus and storm warnings, but each has only a local jurisdiction; and even our National Signal Office, covering as it does the largest region of any, has recognized that our storms and weather are affected by atmospheric conditions far beyond our borders. In 1871 it began to collect ocean data, and since 1875 has compiled a daily weather map of the whole northern hemisphere. There has just come to hand a most extensive work by Buchan,1 published as one of the scientific results of the voyage of the Challenger, which shows month by month the condition of the atmosphere over the whole northern hemisphere.
But statistical and climatic averages are not dynamic meteorology, and it is in this latter field that the general problems of atmospheric pressure and motion press hard for solution. The past decade has seen important memoirs on fundamental questions from the hands of our most able mathematical physicists : those of Helmholtz and Sir William Thomson on vortex motions and stationary waves ; Oberbeck on the general circulation of the air and on cyclonic motions; Hertz on adiabatic motions, and Bezold on non-adiabatic motions ; Buchan, Hann, and Rayleigh on diurnal barometric fluctuations ; E. Poincarée on lunar titles in the atmosphere.
Hitherto, the professional meteorologist has too frequently been only an observer, a statistician, an empiricist, rather than a mechanician, mathematician, and physicist. He has studied the atmosphere out-of-doors, without having had a preliminary indoor training in the laws of fluid motion, so that much that has been written on dynamic meteorology has proved unsatisfactory. In fact, there are even now very few laboratories in the world where the instruction can be given, and thirty years ago there were none; but the recent advent of our foremost physicists into this field of investigation, and the erection of laboratories for all manner of mechanical work, raise our hopes to the highest pitch.
The problems of meteorology are important enough and difficult enough to excite the ambition of the ablest men. By their help, we shall yet make great progress in the prediction not only of daily weather, but of extensive climatic changes and of droughts and floods, months in advance ; eventually we shall be able to state what climates must have obtained in past geological ages.
Here I close this rapid sketch of the various divisions of terrestrial physics. Our German brethren have coined for it the appropriate title “ Geo-physik,” and have already given us some extensive treatises covering the ground that I have indicated. We have thus a distinct branch of geo-physical study that has too rarely been recognized either in our universities or our observatories. A few general remarks, or a chapter in some treatise on geology or physical geography or meteorology, and the subject is dismissed and forgotten, in the midst of the numerous other studies. We maintain seventy American and two hundred and fifty foreign astronomical observatories, two hundred chemical laboratories, and one hundred laboratories for molecular physics, but as yet there is not one in the United States founded expressly for terrestrial physics.
In this great department of science good results may be attained by a system which shall coördinate the several independent lines of investigation. Our Coast Survey may do something in regard to the figure, the size, and the attraction of the earth ; it may even contribute to the elucidation of tides, or currents, or terrestrial magnetism ; the Geological Survey may find it within its powers lightly to touch on the questions of internal heat, plasticity, earthquakes, mountain building, and the evolution of continents and oceans ; the astronomical or naval observatories may study changes of latitude; the Signal Office may see its way clear to study atmospheric problems larger than American weather. But the cosmic problems that I have enumerated need the coöperation of government officials and university educators, and I hopefully look for some patron of science who shall set able men to work in an institution devoted to geophysics, which may well be a component part of a great university. What American schools of science have already done for astronomy, chemistry, geology, electricity, medicine, engineering, and what other schools are doing for history, law, polities, archæology, and linguistics, still remains to be done for various other departments of learning, notably the whole wide range of terrestrial physics.
But lest the scheme which I have outlined be regarded as too wide for immediate adoption, let me single out one great division which presses for recognition. I contend that our Signal Service and State Weather Services should have the collegiate recognition and the moral and material support that would result from the establishment of comprehensive schools of meteorology as one branch of the study of our globe. Of all branches of applied science, meteorology, with, its weather predictions, is that which at the present moment demands the most serious attention from our universities. The professors needed in connection with courses of study preparatory to meteorology are already to be found in several of our universities and technical schools. At these, therefore, it will require but a slight additional labor or expense to conduct the students through a special course in theoretical and practical meteorology and the applications of climatology.
Not to be too indefinite. I may briefly indicate that descriptive or elementary meteorology is already fairly provided for in accessible text-books, but the courses of study required to fit one successfully to cope with the more difficult problems that beset this science would be somewhat as follows : —
Mathematics: through the theory of probabilities, determinants, and differential equations.
Analytical Mechanics : through the general treatises on fluid motion and the tides, and the special treatises on atmospheric motions by Ferrel, Sprung, Helmholtz, Guldberg, and Mohn.
Hydraulics : synopsis of the work of hydraulic experimenters, and especially the treatise of Boussinesq on the movement of water.
Thermo-Dynamics : through Bezold’s treatise on the non-adiabatic processes in the atmosphere.
Molecular Physics : text - book and laboratory course in heat, light, acoustics, mechanics, and electricity.
Graphics: all graphic methods for solving kinematic, static, and kinetic problems, and all methods of cartography and projection.
Observations : parallel with a full course in physical training should be a personal record of dally experience in observations of temperature, moisture, clouds, and other meteorological phenomena ; there should be special determinations of some of the fundamental meteorological constants, and a course of study of daily charts ; the formulation of predictions and their verification by comparison with actual weather subsequently experienced.
When, in 1868, I announced that the Cincinnati Observatory was prepared to begin the experiment of daily weather predictions for the benefit of the residents of that city, we had only the works of Loomis, Espy, Ferrel, Henry, and Schott to study ; and now, at the end of twenty-five years, they are still our American authorities. During this interval, the needs of the country in the matter of weather predictions have been patent to every one, but what have our universities done to stimulate the study of this important subject ? I have not failed to present our needs to several universities, and have sketched out courses of instruction for others, hoping to see them introduced ; and have also sought to introduce elementary courses into high schools and normal schools. In all these, the main object in view was the wide dissemination of training in philosophic and scientific methods of studying the atmosphere and predicting the weather as distinguished from ordinary empiricisms. I advocated the study of dynamic meteorology as distinguished from statistical climatology. As yet, I have heard but of one effort in this direction, — the class of Professor William M. Davis at Harvard. But the frequent inquiries as to how one can learn of the great progress that is being made in the study of the atmosphere, and the equally numerous inquiries as to whether one who devotes himself to meteorology may hope to find means of support, show that intelligent interest in the subject is being aroused. How can I reply discouragingly to these latter inquiries, when the Signal Service and State Weather Services need hundreds of intelligent observers and good local weather predictors ? Any one who can make local weather predictions better than those that are now published daily is sure of employment by business men or by the government. There is no desideratum more deeply felt than that of correct weather predictions : that which is now done only whets the desire for something better, Both within the Signal Office and outside of it, the hope exists that there may continue to be steady improvement in this, the most important practical application of our knowledge of meteorology ; but the scholar will see at once that such progress can be achieved only by enlisting the coöperation of universities that shall train for us many learned and energetic investigators.
Already, with her usual intellectual energy, Germany has taken the initiative. A circular, compiled at my request in 1882 by Professor Frank Waldo, showed Americans at what places in Germany they might study meteorology ; but it also showed the Germans the deficiencies of their own universities in this respect, and in immediate response there started up a vigorous activity : it was as though the authorities had ordered their most eminent physicists, Helmholtz, Bezold, Oberbeck, Sprung, Hertz, Köppen, and others, to join together in lifting the new science from her low estate. At the present moment, Germany leads the world in the development of ideas which were first expounded in America by Espy and Ferrel, and one can hardly keep up with her rapidly advancing literature.
So long as our own mathematicians and physicists hold aloof from these severe studies, so long must American youth go away from American universities to learn of the present state and future growth of meteorology. So long as our universities make no provision for teaching the new aspect of this science, and confine their courses of instruction to a few remarks on the elementary climatology of twenty years ago, so long must the study of meteorology in America be expected to deal only with the superficial appearance of things, without going to the root of the matter. Give our young student physicists a chance to study the laws of motion of storms and the art of prediction, and they will soon make of meteorology a science as exact as is in any way compatible with the complexity of the phenomena.
The field is ripe for the harvest; send the skilled laborers into it. The path to that field runs through the physical laboratory and the mathematical studio of the university.
- Report on the Scientific Results of the Voyage of H M. S. Challenger during the Years 1873-76. Physics and Chemistry, Vol. II. Part 5 : Report on Atmospheric Circulation, by Alexander Buchan. London, 1889. 347 pages, 3 plates, 52 maps.↩