We went from Gibraltar to Berlin in January by way of Italy. The Mediterranean is a charming sea in summer, but in winter is a good deal like the Atlantic. The cause of the blueness of its water is not completely settled; but its sharing this color with Lake Geneva, which is tinged with detritus from the shore, might lead one to ascribe it to substances held in solution. The color is noticeable even in the harbor of Malta, to which we had a pleasant though not very smooth passage of five days.

Here was our first experience of an Italian town of a generation ago. I had no sooner started to take a walk than a so-called guide, who spoke what he thought was English, got on my track, and insisted on showing me everything. If I started toward a shop, he ran in before me, invited me in, asked what I would like to buy, and told the shopman to show the gentleman something. I could not get rid of him till I returned to the hotel, and then he had the audacity to want a fee for his services. I do not think he got it. Everything of interest was easily seen, and we only stopped to take the first Italian steamer to Messina. We touched at Syracuse and Catania, but did not land.

Ætna, from the sea, is one of the grandest sights I ever saw. Its snow-covered cone seems to rise on all sides out of the sea or the plain, and to penetrate the blue sky. In this it gives an impression like that of the Weisshorn seen from Randa, but gains by its isolation.

At Messina, of course, our steamer was visited by a commissionnaire, who asked me in good English whether I wanted a hotel. I told him that I had already decided upon a hotel, and therefore did not need his services. But it turned out that he belonged to the very hotel I was going to, and was withal an American, a native-born Yankee, in fact, and so obviously honest that I placed myself unreservedly in his hands,—something which I never did with one of his profession before or since. He said the first thing was to get our baggage through the custom-house, which he could do without any trouble, at the cost of a franc. He was as good as his word. The Italian custom-house was marked by primitive rigor, and baggage was commonly subjected to a very thorough search. But my man was evidently well known and fully trusted. I was asked to raise the lid of one trunk, which I did; the official looked at it, with his hands in his pockets, gave a nod, and the affair was over. My Yankee friend collected one franc for that part of the business. He told us all about the place, changed our money so as to take advantage of the premium on gold, and altogether looked out for our interests in a way to do honor to his tribe. I thought there might be some curious story of the way in which a New Englander of such qualities could have dropped into such a place, but it will have to be left to imagination.

We reached the Bay of Naples in the morning twilight, after making an unsuccessful attempt to locate Scylla and Charybdis. If they ever existed, they must have disappeared. Vesuvius was now and then lighting up the clouds with its intermittent flame. But we had passed a most uncomfortable night, and the morning was wet and chilly. A view requires something more than the objective to make it appreciated, and the effect of a rough voyage and bad weather was such as to deprive of all its beauty what is considered one of the finest views in the world. Moreover, the experience made me so ill-natured that I was determined that the custom-house officer at the landing should have no fee from me. The only article that could have been subject to duty was on top of everything in the trunk, except a single covering of some loose garment, so that only a touch was necessary to find it. When it came to the examination, the officer threw the top till contemptuously aside, and devoted himself to a thorough search of the bottom. The only unusual object he stumbled upon was a spyglass inclosed in a shield of morocco. Perhaps a gesture and a remark on my part aroused his suspicions. He opened the glass, tried to take it to pieces, inspected it inside and out, and was so disgusted with his failure to find anything contraband in it that he returned everything to the trunk, and let us off.

It is commonly and quite justly supposed that the more familiar the traveler is with the language of the place he visits, the better he will get along. It is a common experience to find that even when you can pronounce the language, you cannot understand what is said. But there are exceptions to all rules, and circumstances now and then occur in which one thus afflicted has an advantage over the native. You can talk to him, while he cannot talk to you. There was an amusing case of this kind at Munich. The only train that would take us to Berlin before nightfall of the same day left at eight o'clock in the morning, by a certain route. There was at Munich what we call a union station. I stopped at the first ticket-office where I saw the word "Berlin" on the glass, asked for a ticket good in the train that was going to leave at eight o'clock the next morning for Berlin, and took what the seller gave me. He was a stupid-looking fellow, so when I got to my hotel I showed the ticket to a friend. "That is not the ticket that you want at all," said he; "it will take you by a circuitous route in a train that does not leave until after nine, and you will not reach Berlin until long after dark." I went directly back to the station and showed my ticket to the agent.

"I—asked—you—for—a—ticket—good—in—the—train—which— leaves—at—eight—o'—clock. This—ticket—is—not—good— in—that—train. Sie—haben—mich—betrÜgen. I—want—you— to—take—the—ticket—back—and—return—me—the—money. What—you—say—can—I—not—understand."

He expostulated, gesticulated, and fumed, but I kept up the bombardment until he had to surrender. He motioned to me to step round into the office, where he took the ticket and returned the money. I mention the matter because taking back a ticket is said to be quite unusual on a German railway.

At Berlin, the leading astronomers then, as now, were FÖrster, director of the observatory, and Auwers, permanent secretary of the Academy of Sciences. I was especially interested in the latter, as we had started in life nearly at the same time, and had done much work on similar lines. It was several days before I made his acquaintance, as I did not know that the rule on the Continent is that the visitor must make the first call, or at least make it known by direct communication that he would be pleased to see the resident; otherwise it is presumed that he does not wish to see callers. This is certainly the more logical system, but it is not so agreeable to the visiting stranger as ours is. The art of making the latter feel at home is not brought to such perfection on the Continent as in England; perhaps the French understand it less than any other people. But none can be pleasanter than the Germans, when you once make their acquaintance; and we shall always remember with pleasure the winter we passed in Berlin.

To-day, Auwers stands at the head of German astronomy. In him is seen the highest type of the scientific investigator of our time, one perhaps better developed in Germany than in any other country. The work of men of this type is marked by minute and careful research, untiring industry in the accumulation of facts, caution in propounding new theories or explanations, and, above all, the absence of effort to gain recognition by being the first to make a discovery. When men are ambitious to figure as Newtons of some great principle, there is a constant temptation to publish unverified speculations which are likely rather to impede than to promote the advance of knowledge. The result of Auwers's conscientiousness is that, notwithstanding his eminence in his science, there are few astronomers of note whose works are less fitted for popular exposition than his. His specialty has been the treatment of all questions concerning the positions and motions of the stars. This work has required accurate observations of position, with elaborate and careful investigations of a kind that offer no feature to attract public attention, and only in exceptional cases lead to conclusions that would interest the general reader. He considers no work as ready for publication until it is completed in every detail.

The old astronomical observations of which I was in quest might well have been made by other astronomers than those of Paris, so while awaiting the end of the war I tried to make a thorough search of the writings of the mediÆval astronomers in the Royal Library. If one knew exactly what books he wanted, and had plenty of time at his disposal, he would find no difficulty in consulting them in any of the great Continental libraries. But at the time of my visit, notwithstanding the cordiality with which all the officials, from Professor Lepsius down, were disposed to second my efforts, the process of getting any required book was very elaborate. Although one could obtain a book on the same day he ordered it, if he went in good time, it was advisable to leave the order the day before, if possible. When, as in the present case, one book only suggests another, this a third, and so on, in an endless chain, the carrying on of an extended research is very tedious.

One feature of the library strongly impressed me with the comparatively backward state of mathematical science in our own country. As is usual in the great European libraries, those books which are most consulted are placed in the general reading-room, where any one can have access to them, at any moment. It was surprising to see amongst these books a set of Crelle's "Journal of Mathematics," and to find it well worn by constant use. At that time, so far as I could learn, there were not more than two or three sets of the Journal in the United States; and these were almost unused. Even the Library of Congress did not contain a set. There has been a great change since that time,—a change in which the Johns Hopkins University took the lead, by inviting Sylvester to this country, and starting a mathematical school of the highest grade. Other universities followed its example to such an extent that, to-day, an American student need not leave his own country to hear a master in any branch of mathematics.

I believe it was Dr. B. A. Gould who called the Pulkova Observatory the astronomical capital of the world. This institution was founded in 1839 by the Emperor Nicholas, on the initiative of his greatest astronomer. It is situated some twelve miles south of St. Petersburg, not far from the railway between that city and Berlin, and gets its name from a peasant village in the neighborhood. From its foundation it has taken the lead in exact measurements relating to the motion of the earth and the positions of the principal stars. An important part of its equipment is an astronomical library, which is perhaps the most complete in existence. This, added to all its other attractions, induced me to pay a visit to Pulkova. Otto Struve, the director, had been kind enough to send me a message, expressing the hope that I would pay him a visit, and giving directions about telegraphing in advance, so as to insure the delivery of the dispatch. The time from Berlin to St. Petersburg is about forty-eight hours, the only through train leaving and arriving in the evening. On the morning of the day that the train was due I sent the dispatch. Early in the afternoon, as the train was stopping at a way station, I saw an official running hastily from one car to another, looking into each with some concern. When he came to my door, he asked if I had sent a telegram to Estafetta. I told him I had. He then informed me that Estafetta had not received it. But the train was already beginning to move, so there was no further chance to get information. The comical part of the matter was that "Estafetta" merely means a post or postman, and that the directions, as Struve had given them, were to have the dispatch sent by postman from the station to Pulkova.

It was late in the evening when the train reached Zarsko-Selo, the railway station for Pulkova, which is about five miles away. The station-master told me that no carriage from Pulkova was waiting for me, which tended to confirm the fear that the dispatch had not been received. After making known my plight, I took a seat in the station and awaited the course of events, in some doubt what to do. Only a few minutes had elapsed when a good-looking peasant, well wrapped in a fur overcoat, with a whip in his hand, looked in at the door, and pronounced very distinctly the words, "Observatorio Pulkova." Ah! this is Struve's driver at last, thought I, and I followed the man to the door. But when I looked at the conveyance, doubt once more supervened. It was scarcely more than a sledge, and was drawn by a single horse, evidently more familiar with hard work than good feeding. This did not seem exactly the vehicle that the great Russian observatory would send out to meet a visitor; yet it was a far country, and I was not acquainted with its customs.

The way in which my doubt was dispelled shows that there is one subject besides love on which difference of language is no bar to the communication of ideas. This is the desire of the uncivilized man for a little coin of the realm. In South Africa, Zulu chiefs, who do not know one other word of English, can say "shilling" with unmistakable distinctness. My Russian driver did not know even this little English word, but he knew enough of the universal language. When we had made a good start on the snow-covered prairie, he stopped his horse for a moment, looked round at me inquiringly, raised his hand, and stretched out two fingers so that I could see them against the starlit sky.

I nodded assent.

Then he drew his overcoat tightly around him with a gesture of shivering from the cold, beat his hands upon his breast as if to warm it, and again looked inquiringly at me.

I nodded again.

The bargain was complete. He was to have two rubles for the drive, and a little something to warm up his shivering breast. So he could not be Struve's man.

There is no welcome warmer than a Russian one, and none in any country warmer than that which the visiting astronomer receives at an observatory. Great is the contrast between the winter sky of a clear moonless night and the interior of a dining-room, forty feet square, with a big blazing fire at one end and a table loaded with eatables in the middle. The fact that the visitor had never before met one of his hosts detracted nothing from the warmth of his reception.

The organizer of the observatory, and its first director, was Wilhelm Struve, father of the one who received me, and equally great as man and astronomer. Like many other good Russians, he was the father of a large family. One of his sons was for ten years the Russian minister at Washington, and as popular a diplomatist as ever lived among us. The instruments which Struve designed sixty years ago still do as fine work as any in the world; but one may suspect this to be due more to the astronomers who handle them than to the instruments themselves.

The air is remarkably clear; the entrance to St. Petersburg, ten or twelve miles north, is distinctly visible, and Struve told me that during the Crimean war he could see, through the great telescope, the men on the decks of the British ships besieging Kronstadt, thirty miles away.

One drawback from which the astronomers suffer is the isolation of the place. The village at the foot of the little hill is inhabited only by peasants, and the astronomers and employees have nearly all to be housed in the observatory buildings. There is no society but their own nearer than the capital. At the time of my visit the scientific staff was almost entirely German or Swedish, by birth or language. In the state, two opposing parties are the Russian, which desires the ascendency of the native Muscovites, and the German, which appreciates the fact that the best and most valuable of the Tsar's subjects are of German or other foreign descent. During the past twenty years the Russian party has gradually got the upper hand; and the result of this ascendency at Pulkova will be looked for with much solicitude by astronomers everywhere.

Once a year the lonely life of the astronomers is enlivened by a grand feast—that of the Russian New Year. One object of the great dining-room which I have mentioned, the largest room, I believe, in the whole establishment, was to make this feast possible. My visit took place early in March, so that I did not see the celebration; but from what I have heard, the little colony does what it can to make up for a year of ennui. Every twenty-five years it celebrates a jubilee; the second came off in 1889.

There is much to interest the visitor in a Russian peasant village, and that of Pulkova has features some of which I have never seen described. Above the door of each log hut is the name of the occupant, and below the name is a rude picture of a bucket, hook, or some other piece of apparatus used in extinguishing fire. Inside, the furniture is certainly meagre enough, yet one could not see why the occupants should be otherwise than comfortable. I know of no good reason why ignorance should imply unhappiness; altogether, there is some good room for believing that the less civilized races can enjoy themselves, in their own way, about as well as we can. What impressed me as the one serious hardship of the peasantry was their hours of labor. Just how many hours of the twenty-four these beings find for sleep was not clear to the visitor; they seemed to be at work all day, and at midnight many of them had to start on their way to St. Petersburg with a cartload for the market. A church ornamented with tinsel is a feature of every Russian village; so also are the priests. The only two I saw were sitting on a fence, wearing garments that did not give evidence of having known water since they were made. One great drawback to the growth of manufactures in Russia is the number of feast days, on which the native operators must one and all abandon their work, regardless of consequences.

The astronomical observations made at Pulkova are not published annually, as are those made at most of the other national observatories; but a volume relating to one subject is issued whenever the work is done. When I was there, the volumes containing the earlier meridian observations were in press. Struve and his chief assistant, Dr. Wagner, used to pore nightly over the proof sheets, bestowing on every word and detail a minute attention which less patient astronomers would have found extremely irksome.

Dr. Wagner was a son-in-law of Hansen, the astronomer of the little ducal observatory at Gotha, as was also our Bayard Taylor. My first meeting with Hansen, which occurred after my return to Berlin, was accompanied with some trepidation. Modest as was the public position that he held, he may now fairly be considered the greatest master of celestial mechanics since Laplace. In what order Leverrier, Delaunay, Adams, and Hill should follow him, it is not necessary to decide. To many readers it will seem singular to place any name ahead of that of the master who pointed out the position of Neptune before a human eye had ever recognized it. But this achievement, great as it was, was more remarkable for its boldness and brilliancy than for its inherent difficulty. If the work had to be done over again to-day, there are a number of young men who would be as successful as Leverrier; but there are none who would attempt to reinvent the methods of Hansen, or even to improve radically upon them. Their main feature is the devising of new and refined methods of computing the variations in the motions of a planet produced by the attraction of all the other planets. As Laplace left this subject, the general character of these variations could be determined without difficulty, but the computations could not be made with mathematical exactness. Hansen's methods led to results so precise that, if they were fully carried out, it is doubtful whether any deviation between the predicted and the observed motions of a planet could be detected by the most refined observation.

At the time of my visit Mrs. Wagner was suffering from a severe illness, of which the crisis passed while I was at Pulkova, and left her, as was supposed, on the road to recovery. I was, of course, very desirous of meeting so famous a man as Hansen. He was expected to preside at a session of the German commission on the transit of Venus, which was to be held in Berlin about the time of my return thither from Pulkova. The opportunity was therefore open of bringing a message of good news from his daughter. Apart from this, the prospect of the meeting might have been embarrassing. The fact is that I was at odds with him on a scientific question, and he was a man who did not take a charitable view of those who differed from him in opinion.

He was the author of a theory, current thirty or forty years ago, that the farther side of the moon is composed of denser materials than the side turned toward us. As a result of this, the centre of gravity of the moon was supposed to be farther from us than the actual centre of her globe. It followed that, although neither atmosphere nor water existed on our side of the moon, the other side might have both. Here was a very tempting field into which astronomical speculators stepped, to clothe the invisible hemisphere of the moon with a beautiful terrestrial landscape, and people it as densely as they pleased with beings like ourselves. If these beings should ever attempt to explore the other half of their own globe, they would find themselves ascending to a height completely above the limits of their atmosphere. Hansen himself never countenanced such speculations as these, but confined his claims to the simple facts he supposed proven.

In 1868 I had published a little paper showing what I thought a fatal defect, a vicious circle in fact, in Hansen's reasoning on this subject. Not long before my visit, Delaunay had made this paper the basis of a communication to the French Academy of Sciences, in which he not only indorsed my views, but sought to show the extreme improbability of Hansen's theory on other grounds.

When I first reached Germany, on my way from Italy, I noticed copies of a blue pamphlet lying on the tables of the astronomers. Apparently, the paper had been plentifully distributed; but it was not until I reached Berlin that I found it was Hansen's defense against my strictures,—a defense in which mathematics were not unmixed with seething sarcasm at the expense of both Delaunay and myself. The case brought to mind a warm discussion between Hansen and Encke, in the pages of a scientific journal, some fifteen years before. At the time it had seemed intensely comical to see two enraged combatants—for so I amused myself by fancying them—hurling algebraic formulÆ, of frightful complexity, at each other's heads. I did not then dream that I should live to be an object of the same sort of attack, and that from Hansen himself.

To be revised, pulled to pieces, or superseded, as science advances, is the common fate of most astronomical work, even the best. It does not follow that it has been done in vain; if good, it forms a foundation on which others will build. But not every great investigator can look on with philosophic calm when he sees his work thus treated, and Hansen was among the last who could. Under these circumstances, it was a serious question what sort of reception Hansen would accord to a reviser of his conclusions who should venture to approach him. I determined to assume an attitude that would show no consciousness of offense, and was quite successful. Our meeting was not attended by any explosion; I gave him the pleasant message with which I was charged from his daughter, and, a few days later, sat by his side at a dinner of the German commission on the coming transit of Venus.

As Hansen was Germany's greatest master in mathematical astronomy, so was the venerable Argelander in the observational side of the science. He was of the same age as the newly crowned Emperor, and the two were playmates at the time Germany was being overrun by the armies of Napoleon. He was held in love and respect by the entire generation of young astronomers, both Germans and foreigners, many of whom were proud to have had him as their preceptor. Among these was Dr. B. A. Gould, who frequently related a story of the astronomer's wit. When with him as a student, Gould was beardless, but had a good head of hair. Returning some years later, he had become bald, but had made up for it by having a full, long beard. He entered Argelander's study unannounced. At first the astronomer did not recognize him.

"Do you not know me, Herr Professor?"

The astronomer looked more closely. "Mine Gott! It is Gould mit his hair struck through!"

Argelander was more than any one else the founder of that branch of his science which treats of variable stars. His methods have been followed by his successors to the present time. It was his policy to make the best use he could of the instruments at his disposal, rather than to invent new ones that might prove of doubtful utility. The results of his work seem to justify this policy.

We passed the last month of the winter in Berlin waiting for the war to close, so that we could visit Paris. Poor France had at length to succumb, and in the latter part of March, we took almost the first train that passed the lines.

Delaunay was then director of the Paris Observatory, having succeeded Leverrier when the emperor petulantly removed the latter from his position. I had for some time kept up an occasional correspondence with Delaunay, and while in England, the autumn before, had forwarded a message to him, through the Prussian lines, by the good offices of the London legation and Mr. Washburn. He was therefore quite prepared for our arrival. The evacuation of a country by a hostile army is rather a slow process, so that the German troops were met everywhere on the road, even in France. They had left Paris just before we arrived; but the French national army was not there, the Communists having taken possession of the city as fast as the Germans withdrew. As we passed out of the station, the first object to strike our eyes was a flaming poster addressed to "Citoyens," and containing one of the manifestoes which the Communist government was continually issuing.

Of course we made an early call on Mr. Washburn. His career in Paris was one of the triumphs of diplomacy; he had cared for the interests of German subjects in Paris in such a way as to earn the warm recognition both of the emperor and of Bismarck, and at the same time had kept on such good terms with the French as to be not less esteemed by them. He was surprised that we had chosen such a time to visit Paris; but I told him the situation, the necessity of my early return home, and my desire to make a careful search in the records of the Paris Observatory for observations made two centuries ago. He advised us to take up our quarters as near to the observatory as convenient, in order that we might not have to pass through the portions of the city which were likely to be the scenes of disturbance.

We were received at the observatory with a warmth of welcome that might be expected to accompany the greeting of the first foreign visitor, after a siege of six months. Yet a tinge of sadness in the meeting was unavoidable. Delaunay immediately began lamenting the condition of his poor ruined country, despoiled of two of its provinces by a foreign foe, condemned to pay an enormous subsidy in addition, and now the scene of an internal conflict the end of which no one could foresee.

While I was mousing among the old records of the Paris Observatory, the city was under the reign of the Commune and besieged by the national forces. The studies had to be made within hearing of the besieging guns; and I could sometimes go to a window and see flashes of artillery from one of the fortifications to the south. Nearly every day I took a walk through the town, occasionally as far as the Arc de Triomphe. The story of the Commune has been so often written that I cannot hope to add anything to it, so far as the main course of events is concerned. Looking back on a sojourn at so interesting a period, one cannot but feel that a golden opportunity to make observations of historic value was lost. The fact is, however, that I was prevented from making such observations not only by my complete absorption in my work, but by the consideration that, being in what might be described as a semi-official capacity, I did not want to get into any difficulty that would have compromised the position of an official visitor. I should not deem what we saw worthy of special mention, were it not that it materially modifies the impressions commonly given by writers on the history of the Commune. What an historian says may be quite true, so far as it goes, and yet may be so far from the whole truth as to give the reader an incorrect impression of the actual course of events. The violence and disease which prevail in the most civilized country in the world may be described in such terms as to give the impression of a barbarous community. The murder of the Archbishop of Paris and of the hostages show how desperate were the men who had seized power, yet the acts of these men constitute but a small part of the history of Paris during that critical period.

What one writes at the time is free from the suspicion that may attach to statements not recorded till many years after the events to which they relate. The following extract from a letter which I wrote to a friend, the day after my arrival, may therefore be taken to show how things actually looked to a spectator:—

Dear Charlie,—Here we are, on this slumbering volcano. Perhaps you will hear of the burst-up long before you get this. We have seen historic objects which fall not to the lot of every generation, the barricades of the Paris streets. As we were walking out this morning, the pavement along one side of the street was torn up for some distance, and used to build a temporary fort. Said fort would be quite strong against musketry or the bayonet; but with heavy shot against it, I should think it would be far worse than nothing, for the flying stones would kill more than the balls.

The streets are placarded at every turn with all sorts of inflammatory appeals, and general orders of the ComitÉ Central or of the Commune. One of the first things I saw last night was a large placard beginning "Citoyens!" Among the orders is one forbidding any one from placarding any orders of the Versailles government under the severest penalties; and another threatening with instant dismissal any official who shall recognize any order issuing from the said government.

I must do all hands the justice to say that they are all very well behaved. There is nothing like a mob anywhere, so far as I can find. I consulted my map this morning, right alongside the barricade and in full view of the builders, without being molested, and wife and I walked through the insurrectionary districts without being troubled or seeing the slightest symptoms of disturbance. The stores are all open, and every one seems to be buying and selling as usual. In all the cafÉs I have seen, the habituÉs seem to be drinking their wine just as coolly as if they had nothing unusual on their minds.

From this date to that of our departure I saw nothing suggestive of violence within the limited range of my daily walks, which were mostly within the region including the Arc de Triomphe, the HÔtel de Ville, and the observatory; the latter being about half a mile south of the Luxembourg. The nearest approach to a mob that I ever noticed was a drill of young recruits of the National Guard, or a crowd in the court of the Louvre being harangued by an orator. With due allowance for the excitability of the French nature, the crowd was comparatively as peaceable as that which we may see surrounding a gospel wagon in one of our own cities. A drill-ground for the recruits happened to be selected opposite our first lodgings, beside the gates of the Luxembourg. This was so disagreeable that we were glad to accept an invitation from Delaunay to be his guests at the observatory, during the remainder of our stay. We had not been there long before the spacious yard of the observatory was also used as a drill-ground; and yet later, two or three men were given billets de logement upon the observatory; but I should not have known of the latter occurrence, had not Delaunay told me. I believe he bought the men off, much as one pays an organ-grinder to move on. In one of our walks we entered the barricade around the HÔtel de Ville, and were beginning to make a close examination of a mitrailleuse, when a soldier (beg his pardon, un citoyen membre de la Garde Nationale) warned us away from the weapon. The densest crowd of Communists was along the Rue de Rivoli and in the region of the Colonne VendÔme, where some of the principal barricades were being erected. But even here, not only were the stores open as usual, but the military were doing their work in the midst of piles of trinkets exposed for sale on the pavement by the shopwomen. The order to destroy the Column was issued before we left, but not executed until later. I have no reason to suppose that the shopwomen were any more concerned while the Column was being undermined than they were before. To complete the picture, not a policeman did we see in Paris; in fact, I was told that one of the first acts of the Commune had been to drive the police away, so that not one dared to show himself.

An interesting feature of the sad spectacle was the stream of proclamations poured forth by the Communist authorities. They comprised not only decrees, but sensational stories of victories over the Versailles troops, denunciations of the Versailles government, and even elaborate legal arguments, including a not intemperate discussion of the ethical question whether citizens who were not adherents of the Commune should be entitled to the right of suffrage. The conclusion was that they should not. The lack of humor on the part of the authorities was shown by their commencing one of a rapid succession of battle stories with the words, "Citoyens! Vous avez soif de la vÉritÉ!" The most amusing decree I noticed ran thus:—

"Article I. All conscription is abolished.

"Article II. No troops shall hereafter be allowed in Paris, except the National Guard.

"Article III. Every citizen is a member of the National Guard."

We were in daily expectation and hope of the capture of the city, little imagining by what scenes it would be accompanied. It did not seem to my unmilitary eye that two or three batteries of artillery could have any trouble in demolishing all the defenses, since a wall of paving-stones, four or five feet high, could hardly resist solid shot, or prove anything but a source of destruction to those behind it if attacked by artillery. But the capture was not so easy a matter as I had supposed.

We took leave of our friend and host on May 5, three weeks before the final catastrophe, of which he wrote me a graphic description. As the barricades were stormed by MacMahon, the Communist line of retreat was through the region of the observatory. The walls of the building and of the yard were so massive that the place was occupied as a fort by the retreating forces, so that the situation of the few non-combatants who remained was extremely critical. They were exposed to the fire of their friends, the national troops, from without, while enraged men were threatening their lives within. So hot was the fusillade that, going into the great dome after the battle, the astronomer could imagine all the constellations of the sky depicted by the bullet-holes. When retreat became inevitable, the Communists tried to set the building on fire, but did not succeed. Then, in their desperation, arrangements were made for blowing it up; but the most violent man among them was killed by a providential bullet, as he was on the point of doing his work. The remainder fled, the place was speedily occupied by the national troops, and the observatory with its precious contents was saved.

The Academy of Sciences had met regularly through the entire Prussian siege. The legal quorum being three, this did not imply a large attendance. The reason humorously assigned for this number was that, on opening a session, the presiding officer must say, Messieurs, la sÉance est ouverte, and he cannot say Messieurs unless there are at least two to address. At the time of my visit a score of members were in the city. Among them were Elie de Beaumont, the geologist; Milne-Edwards, the zoÖlogist; and Chevreul, the chemist. I was surprised to learn that the latter was in his eighty-fifth year; he seemed a man of seventy or less, mentally and physically. Yet we little thought that he would be the longest-lived man of equal eminence that our age has known. When he died, in 1889, he was nearly one hundred and three years old. Born in 1786, he had lived through the whole French Revolution, and was seven years old at the time of the Terror. His scientific activity, from beginning to end, extended over some eighty years. When I saw him, he was still very indignant at a bombardment of the Jardin des Plantes by the German besiegers. He had made a formal statement of this outrage to the Academy of Sciences, in order that posterity might know what kind of men were besieging Paris. I suggested that the shells might have fallen in the place by accident; but he maintained that it was not the case, and that the bombardment was intentional.

The most execrated man in the scientific circle at this time was Leverrier. He had left Paris before the Prussian siege began, and had not returned. Delaunay assured me that this was a wise precaution on his part; for had he ventured into the city he would have been mobbed, or the Communists would have killed him as soon as caught. Just why the mob should have been so incensed against one whose life was spent in the serenest fields of astronomical science was not fully explained. The fact that he had been a senator, and was politically obnoxious, was looked on as an all-sufficient indictment. Even members of the Academy could not suppress their detestation of him. Their language seemed not to have words that would fully express their sense of his despicable meanness, not to say turpitude.

Four years later I was again in Paris, and attended a meeting of the Academy of Sciences. In the course of the session a rustle of attention spread over the room, as all eyes were turned upon a member who was entering rather late. Looking toward the door, I saw a man of sixty, a decided blond, with light chestnut hair turning gray, slender form, shaven face, rather pale and thin, but very attractive, and extremely intellectual features. As he passed to his seat hands were stretched out on all sides to greet him, and not until he sat down did the bustle caused by his entrance subside. He was evidently a notable.

"Who is that?" I said to my neighbor.

"Leverrier."

Delaunay was one of the most kindly and attractive men I ever met. We spent our evenings walking in the grounds of the observatory, discussing French science in all its aspects. His investigation of the moon's motion is one of the most extraordinary pieces of mathematical work ever turned out by a single person. It fills two quarto volumes, and the reader who attempts to go through any part of the calculations will wonder how one man could do the work in a lifetime. His habit was to commence early in the morning, and work with but little interruption until noon. He never worked in the evening, and generally retired at nine. I felt some qualms of conscience at the frequency with which I kept him up till nearly ten. I found it hopeless to expect that he would ever visit America, because he assured me that he did not dare to venture on the ocean. The only voyage he had ever made was across the Channel, to receive the gold medal of the Royal Astronomical Society for his work. Two of his relatives—his father and, I believe, his brother—had been drowned, and this fact gave him a horror of the water. He seemed to feel somewhat like the clients of the astrologists, who, having been told from what agencies they were to die, took every precaution to avoid them. I remember, as a boy, reading a history of astrology, in which a great many cases of this sort were described; the peculiarity being that the very measures which the victim took to avoid the decree of fate became the engines that executed it. The death of Delaunay was not exactly a case of this kind, yet it could not but bring it to mind. He was at Cherbourg in the autumn of 1872. As he was walking on the beach with a relative, a couple of boatmen invited them to take a sail. Through what inducement Delaunay was led to forget his fears will never be known. All we know is that he and his friend entered the boat, that it was struck by a sudden squall when at some distance from the land, and that the whole party were drowned.

There was no opposition to the reappointment of Leverrier to his old place. In fact, at the time of my visit, Delaunay said that President Thiers was on terms of intimate friendship with the former director, and he thought it not at all unlikely that the latter would succeed in being restored. He kept the position with general approval till his death in 1877.

The only occasion on which I met Leverrier was after the incident I have mentioned, in the Academy of Sciences. I had been told that he was incensed against me on account of an unfortunate remark I had made in speaking of his work which led to the discovery of Neptune. I had heard this in Germany as well as in France, yet the matter was so insignificant that I could hardly conceive of a man of philosophic mind taking any notice of it. I determined to meet him, as I had met Hansen, with entire unconsciousness of offense. So I called on him at the observatory, and was received with courtesy, but no particular warmth. I suggested to him that now, as he had nearly completed his work on the tables of the planets, the question of the moon's motion would be the next object worthy of his attention. He replied that it was too large a subject for him to take up.

To Leverrier belongs the credit of having been the real organizer of the Paris Observatory. His work there was not dissimilar to that of Airy at Greenwich; but he had a much more difficult task before him, and was less fitted to grapple with it. When founded by Louis XIV. the establishment was simply a place where astronomers of the Academy of Sciences could go to make their observations. There was no titular director, every man working on his own account and in his own way. Cassini, an Italian by birth, was the best known of the astronomers, and, in consequence, posterity has very generally supposed he was the director. That he failed to secure that honor was not from any want of astuteness. It is related that the monarch once visited the observatory to see a newly discovered comet through the telescope. He inquired in what direction the comet was going to move. This was a question it was impossible to answer at the moment, because both observations and computations would be necessary before the orbit could be worked out. But Cassini reflected that the king would not look at the comet again, and would very soon forget what was told him; so he described its future path in the heavens quite at random, with entire confidence that any deviation of the actual motion from his prediction would never be noted by his royal patron.

One of the results of this lack of organization has been that the Paris Observatory does not hold an historic rank correspondent to the magnificence of the establishment. The go-as-you-please system works no better in a national observatory than it would in a business institution. Up to the end of the last century, the observations made there were too irregular to be of any special importance. To remedy this state of things, Arago was appointed director early in the present century; but he was more eminent in experimental physics than in astronomy, and had no great astronomical problem to solve. The result was that while he did much to promote the reputation of the observatory in the direction of physical investigation, he did not organize any well-planned system of regular astronomical work.

When Leverrier succeeded Arago, in 1853, he had an extremely difficult problem before him. By a custom extending through two centuries, each astronomer was to a large extent the master of his own work. Leverrier undertook to change all this in a twinkling, and, if reports are true, without much regard to the feelings of the astronomers. Those who refused to fall into line either resigned or were driven away, and their places were filled with men willing to work under the direction of their chief. Yet his methods were not up to the times; and the work of the Paris Observatory, so far as observations of precision go, falls markedly behind that of Greenwich and Pulkova.

In recent times the institution has been marked by an energy and a progressiveness that go far to atone for its former deficiencies. The successors of Leverrier have known where to draw the line between routine, on the one side, and initiative on the part of the assistants, on the other. Probably no other observatory in the world has so many able and well-trained young men, who work partly on their own account, and partly in a regular routine. In the direction of physical astronomy the observatory is especially active, and it may be expected in the future to justify its historic reputation.