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hopelessness of the time in the passive endurance of Stoicism or the passive piety of religion. Let us hear Tacitus on the redeeming features of his day: Non tamen adeo virtutum sterile seculum ut non et bona exempla prodiderit. Comitatæ profugos liberos matres; secuta maritos in exsilia conjuges; propinqui audentes, constantes generi; contumax etiam adversus tormenta servorum fides; supremæ clarorum virorum necessitates et laudatis antiquorum mortibus pares exitus.' (Hist. i. 3). The virtues commemorated are those of suffering, not of action. The Christian martyr going cheerfully to execution, the philosopher opening his veins on a hint from the Emperor, perhaps did the best that was open to them under the evil conditions of the times. But none the less they contented themselves with an insufficient ideal. They accepted the attitude of the oriental, whose mind turns in on itself, who abandons the outer world as the domain of fate or chance, and seeks within himself for a hiding-place from which he can look on fate and chance with indifference. They turned their backs on the nobler lesson which Greece had taught, and which remains the most precious heritage that the ancient world has handed down to posterity, the resolve to rule and transform the conditions of the outer world so as to make it a fit habitation for reasonable beings. Political science, the effort to enjoy a free life in a well-ordered state, dates its origin from the experiments of Greek statesmen and the thoughts of Greek philosophers. It is the birthright of Europe, the gift that sets the politics of the West above those of the East. It is the salt of those nations that hold fast to the political faith. With it there is hope for faults being cured and difficulties surmounted. This salt was lacking to the empire of the Caesars. It was an organism without life, whose corruption was the inevitable result of its continuance.
Such, for good and for evil, was the government established by Cæsar's victories. Its acceptance may have been rendered necessary by the blindness and the incapacity of the Republican statesmen of Rome; yet that acceptance was not a counsel of perfection, but a counsel of despair.* It may be that the political life of nations has, during thousands of years, again and again reverted to the lines which Cæsar drew,' but only because the weakness of political faith, and the despondency of sloth and cowardice, has so often led the nations to abdicate the performance of their own duties and to renounce the true ideals of politics. Such a destiny may be submitted to as a miserable
*We borrow the application of the phrase from Mr. Goldwin Smith. † Mommsen, Hist. of Rome,' vol. iv. p. 458.
necessity; we may even recognise that necessity as an inevitable stage in the process of the world's history: but we cannot love the head that judged that the highest was impossible, or the hand that crushed out the possibilities of a nobler future.
ART. VII.-1. Einiges über Witterungs-Angaben gemeinfässlich dargelegt. Von Hermann Kopp. Braunschweig, 1879. 2. Weather Charts and Storm Warnings. By Robert H. Scott, F.R.S. London, 1876.
3. Grundzüge der Meteorologie.
Die Lehre von Wind und Wetter, nach den neuesten Forschungen gemeinfässlich dargestellt. Von H. Mohu. Berlin, 1879.
4. Modern Meteorology: a Series of Lectures delivered under the auspices of the Meteorological Society in 1878. London, 1879.
5. Report of the Meteorological Council to the Royal Society for the period of ten Months ending 31st of March, 1878. Presented to Parliament, 1878.
6. Atlas des Mouvements Généraux de l'Atmosphère, Année 1864, Juin-Décembre, rédigé par l'Observatoire Impérial de Paris. Paris, 1868.
7. Annual Report of the Chief Signal Officer to the Secretary of War for the Year 1877. Government Printing Office, Washington, 1878.
8. The Cycle of Sunspots and of Rainfall in Southern India. By J. Norman Lockyer, W. W. Hunter, and E. D. Archibald. London, 1879.
HEN Arago, in the 'Annuaire du Bureau des Longitudes ' for 1846, pronounced his authoritative opinion, and even printed it in italics-' Jamais, quels que puissent être les progrès des sciences, les savants de bonne foi et soucieux de leur réputation ne se hasarderont à prédire le temps'-he never anticipated that within a quarter of a century from his death there would hardly be a country in Europe which had not established an office for the avowed purpose of weather prediction, in some form or other; much less that in the United States, not only would the gratuitous services of almost the entire engineer corps of the army be devoted to the duty of weather observation and prediction, but a sum of over a thousand dollars a-day would be voted annually to defray the cost of the apparatus, the transmission of telegrams, and the publication of charts.
Some basis of solid value to the public must exist to account for such a general popularity of the weather service, and it will be interesting to trace, first, the rise of existing systems; then to describe briefly the methods on which they work and the results alleged to be attained; and finally to point out the prospects of the further advancement of the science.
This order of treatment has been admirably followed out by Professor Hermann Kopp, the well-known author of the History of Chemistry,' who has developed the substance of a lecture he delivered about two years ago at Heidelberg into the work which heads our list. He assumes three stages of weather enquiry, the first confining itself to a history of past weather, the second to a record of present weather, while the third has chosen as its main object the foretelling the weather of the future.
It is evident that until the invention of the electric telegraph no real advance from the first to the second stage was possible. Although attempts had been made (as by Kämtz in 1833) to set down on charts, a week or so after date, the actual conditions of weather prevailing at a given hour over a considerable area, the interest excited by any such representations was as nothing compared with that aroused by any picture, however incomplete, of the weather prevailing all around us on the very morning of the day on which we study the chart.
It is worth notice that Leverrier, to whom weather telegraphy in Europe, in its present form, may be said to owe its origin, distinctly disclaimed any idea of prophecy as distinct from Storm Warnings for his projected system of weather telegraphy. In a letter which he addressed to Sir G. Airy in 1860, requesting the co-operation of England in his scheme of telegraphy, he said: -'Signaler un ouragan dès qu'il apparaîtra en un point de l'Europe, le suivre dans sa marche au moyen du télégraphe, et informer en temps utile les côtes qu'il pourra visiter, tel devra être le dernier résultat de l'organisation que nous poursuivons.'
It is evident that the entire amount of prophecy implied in this proposal is an assumption of knowledge of the path and rate of motion of a storm, on both of which points our experience plainly shows that the knowledge possessed by meteorologists is still very incomplete, and is likely to remain so for the present.
As regards the third stage of Professor Kopp's classification, it is undeniable that attempts to prophesy weather have been made from the very earliest times, and the ready sale at the present day of Mathieu de la Drome's Le triple almanach, indicateur du temps pour 18-, indispensable à tout le monde,' &c. &c., and of Old Moore's Almanack, shows that at all events credulity
credulity has not vanished from the earth. To give an instance of the degree to which this state of mind prevails, we have heard, on the authority of a gentleman who for fifty years compiled Moore's Almanack, that on one occasion the publishers resolved to omit a table setting forth the influence of the moon on the various organs of the human frame! That year they issued an extra large edition of about 10,000 copies, the major part of which were left on their hands, the omission having rendered them utterly unsaleable in the agricultural districts.
Among the earliest systematic attempts to gain a knowledge of the weather changes actually in progress, have been the constant endeavours to trace a connection between weather and astronomical phenomena. Even at the present day astrometeorology has abundant votaries, and the belief in the falselycalled 'Herschel's Rules' for the influence of lunar phases on the weather, however absurd, is too widely spread to be entirely ignored. Of late years a theory which must be regarded as belonging to astro-meteorology has again come to the front, and is most clearly summarized in the joint production of Messrs. Lockyer, Hunter, and Archibald. This is the doctrine of the relation of sun-spot periodicity to meteorological phenomena. With reference to the practical results of this theory, it must be admitted that the time for prophecy has not yet arrived. Its advocates have pointed to the anomalous weather of 1879 in Western Europe, and have endeavoured to connect this weather with the protracted duration of the existing conditions of solar inactivity; but we cannot ignore the fact that this state of the sun's surface has been of long standing, while the severity of the weather has not been so. There was as great a freedom from spots on the sun's surface in 1878 as in 1879; and yet, though 1878 was by no means a hot or dry year, the conditions of its weather were far from being identical with those of 1879. Was there a single individual among the sun-spot theorists to come forward last February and tell us that we had not a chance of a warm day till July?
The fact is, that recent prophecies of coming weather for a month or so in advance have been conspicuous failures, whether these have been to the effect that the summer of 1879 was to be marked by an unheard-of drought, or that England was to be visited in July by extraordinary heat and a more than Egyptian darkness, which should exterminate most of the population. When we find that people apparently rational have listened to such ravings, we need hardly wonder at the credulity which admits to a place in the 'Times' columns a letter announcing that wet and dry years occur at triennial intervals, a theory
which the slightest examination is sufficient to overthrow. It is, however, time to pass from these failures to what is actually being done, in 1879, in the way of scientific weather prediction, and to trace the development of the existing systems.
The first who appears to have really collated newspaper reports, and thereby to have constructed weather maps, was, as we have already said, Kämtz, who, in 1833 (as he states in his 'Repertorium für Meteorologie '), began to extract the weather notices given in the Vossische Zeitung' of Berlin. Long, however, before his time, and even prior to 1792, Lavoisier, with the marvellous insight which characterized all his work, stated his conviction that useful weather forecasts might be published in the newspapers. In the introduction to Leverrier's 'Atlas des Mouvements généraux de l'Atmosphère pour 1864' (at p. 13), we find in a note the following statement :
Lavoisier reproduit dans une seconde Note les règles pour prédire le temps, et il conclut en ces termes: " que la prédiction des changements qui doivent arriver au temps est un art qui a ses principes et ses règles, qui exige une grande expérience et l'attention d'un physicien très-exercé; que les données nécessaires pour cet art sont: 1o L'observation habituelle et journalière des variations de la hauteur du mercure dans le baromètre, la force et la direction des vents à différentes élévations, l'état hygrométrique de l'air. Avec toutes ces données, il est presque toujours possible de prévoir un jour ou deux à l'avance, avec une très-grande probabilité, le temps qu'il doit faire; on pense même qu'il ne serait pas impossible de publier tous les matins un journal de prédiction qui serait d'une grande utilité pour la société."'
Lavoisier himself had predecessors in Lewis Evans and Franklin, who had discovered the fact of storm motion as early as 1740-50. Mr. Scott tells us, 'Weather Charts and Storm Warnings,' p. 80 :—
The earliest notice of it which we can discover is an entry on a map of Virginia, published in 1747, by Lewis Evans, to the effect that "all our great storms begin to leeward." Franklin, in 1760, followed in the same strain, but it appears that his attention had been caught, at an earlier period, in 1743, by the fact of his being prevented, by the clouds brought by a hurricane, from observing a lunar eclipse at Philadelphia, while the eclipse was seen at Boston, which lies further to the north-eastward, before the storm came on.'
It took, however, more than half a century to realize the hopes of Lavoisier; and it was not until 1847 that the idea of employing in the service of weather study the newly-invented electric telegraph was proposed. As far as we know, the first proposal came from Redfield, and appeared in the American Journal of Science and Art' for that year. In 1848, however, one now