This feature, then, it seems to me, gives Dr. Dohrn's laboratory its greatest value as an educational factor, as a moving force in the biological world. It is true that the new-comer there is likely to be struck at first with a sense of isolation, and to wonder at the seeming exclusiveness of the workers, the self-absorption of each and every one. Outside the management, whom he meets necessarily, no one pays the slightest attention to him at first, or seems to be aware of his existence. He is simply a.s.signed to a room or table, told to ask for what he wants, and left to his own devices. As he walks along the hallways he sees tacked on the doors the cards of biologists from all over the world, exposing names with which he has long been familiar.

He understands that the bearers of the names are at work within the designated rooms, but no one offers to introduce him to them, and for some time, perhaps, he does not so much as see them, nor would he recognize them if he did. He feels strange and isolated in the midst of this stronghold of his profession.

But soon this feeling leaves him. He begins to meet his fellow-workers casually here and there--in the hallways, at the distributing-tanks, in the library. There are no formal gatherings, and there are some workers who never seem to affiliate at all with the others; but in the long-run, here as elsewhere, kindred spirits find one another out; and even the unsocial ones take their share, whether or no, in the indefinable but very sensible influence of ma.s.sed numbers. Presently some one suggests to the new-comer that he join some of the others of a Wednesday or Sat.u.r.day evening, at a rendezvous where a number of them meet regularly.

He goes, under escort of his sponsor, and is guided through one of those narrow, dark, hill-side streets of Naples where he would hardly feel secure to go alone, to a little wine-shop in what seems a veritable dungeon--a place which, if a stranger in Naples, he would never even remotely think of entering. But there he finds his confreres of the laboratory gathered about a long table, with the most conglomerate groups of Neapolitans of a seemingly doubtful cla.s.s at their elbows.

Each biologist has a caraffa of light wine on the table before him, and all are smoking. And, staid men of science that they are, they are chattering away on trivial topics with the animation of a company of school-boys. The stock language is probably German, for this bohemian gathering is essentially a German inst.i.tution; but the Germans are polyglots, and you will hardly find yourself lost in their company, whatever your native tongue.

Your companions will tell you that for years the laboratory fraternity have met twice a week at this homely but hospitable establishment. The host, honest Dominico Vincenzo Bifulco, will gladly corroborate the statement by bringing out for inspection a great blank-book in which successive companies of his guests from the laboratory have scrawled their names, written epigrams, or made clever sketches. That book will some day be treasured in the library of a bibliophile, but that will not be until Bifulco is dead, for while he lives he will never part with it.

One comes to look upon this bohemian wine-shop as an adjunct of the laboratory, and to feel that the free-and-easy meetings there are in their way as important for the progress of science as the private seances of the individual workers in the laboratory itself. Not because scientific topics are discussed here, though doubtless that sometimes happens, but because of that vitalizing influence of the contact of kindred spirits of which I am speaking, and because this is the one place where a considerable number of the workers at the laboratory meet together with regularity.

The men who enter into such a.s.sociations go out from them revitalized, full of the spirit of propaganda. Returned to their own homes, they agitate the question of organizing marine laboratories there; and it is largely through the efforts of the graduates, so to say, of the Naples laboratory that similar inst.i.tutions have been established all over the world.

Thanks largely to the original efforts of Dr. Dohrn, nearly all civilized countries with a coast-line now have their marine laboratories. France has half a dozen, two of them under government control. Russia has two on the Black Sea and one on the French Mediterranean coast. Great Britain has important stations at St.

Andrews, at Liverpool, and at Plymouth. The Scandinavian peninsula has also three important stations. Germany shows a paucity by comparison, which, however, is easily understood when one reflects that the mother-laboratory at Naples is essentially a German inst.i.tution despite its location.

The American stations are located at Woods' Holl and at Cold Spring Harbor, on opposite coasts of Long Island Sound. The j.a.panese station is an adjunct of Tokio University. For the rest, the minor offspring of the Naples laboratory are too numerous to be cited here. Nor can I enter into any details regarding even the more important ones. Each in its way enters into the same general line of work, varying the details according to the bent of mind of individual directors and the limitations of individual resources. But in the broader outlines the aim of all is the same, and what we have seen at Naples is typical of what is best in all the others.

VI. ERNST HAECKEL AND THE NEW ZOOLOGY

THE DREAM CITY

THE train crept on its tortuous way down the picturesque valley of the little Saale. At last we saw, high above us, on a jutting crag, three quaint old castles, in one of which, as we knew from our _Baedeker_; Goethe at one time lived. We were entering the region of traditions.

Soon we knew we should be pa.s.sing that famous battle-field on which Napoleon, in 1806, sealed the fate of Germany for a generation. But this spot, as seen from the car window, bore no emblem to distinguish it, and before we were quite sure that we had reached it we had in point of fact pa.s.sed on, and the train was coming to a stop. "Jena!" called the guard, and the scramble for "luggage" began, leaving us for the moment no place for other thoughts than to make sure that all our various parcels were properly dragged out along with ourselves. For a wonder no Dienstman appeared to give us aid--showing how unexpected is the arrival of any wayfarer at this untoward season--and for a moment one seemed in danger of being reduced to the unheard-of expedient of carrying one's own satchel. But, fortunately, one is rescued from this most un-German predicament by the porter of a waiting hotel omnibus, and so at last we have time to look about us, and to awaken to a realizing sense that we have reached the land of traditions; that we have come to Mecca; that we are in the quondam home of Guericke, Fichte, Goethe, Schiller, Oken, and Gagenbaur; in the present home of Haeckel.

The first glimpse of a mountain beaming down at us from across the way was in admirable conformity with our expectations, but for the rest, the vicinage of the depot presented a most distressing air of modernity. A cl.u.s.ter of new buildings--some of them yet unfinished--stared back at us and the mountain with the most barefaced aspect of cosmopolitanism. Was this, then, Jena, the home of traditions? Or were we entering some Iowa village, where the first settlers still live who but yesterday banished the prairie-dog and the buffalo?

But this disappointment and its ironical promptings were but fleeting.

Five minutes' drive and we were in the true Jena with the real flavor of mediaeval-ism about us. Here is the hostelry where Luther met the Swiss students in 1522. There is nothing in that date to suggest our Iowa village, nor in the aspect of the hostelry itself, thank fortune. And there rises the spire of the city church, up the hill yonder, which was aging, as were most of the buildings that still flank it, when Luther made that memorable visit. America was not discovered, let alone Iowa, when these structures were erected. Now, sure enough, we are in the dream city.

A dream city it truly seems, when one comes to wander through its narrow, tortuous streets, between time-stained walls, amid its rustic population. Coming from Berlin, from Dresden, from Leipzig--not to mention America--one feels as if he had stepped suddenly back two or three centuries into the past. There are some evidences of modernity that mar the illusion, to be sure; but the preponderance of the old-time emblems is sufficient to leave the mind in a delightful glow of reminiscences. As a whole, the aspect of the central portion of the village--of the true Jena--cannot greatly have changed since the days when Luther stopped here on his way to Wittenberg; surely not since 1662, when the mighty young Leibnitz, the Aristotle of Germany, came to Jena to study under Weigel, the most famous of German mathematicians of that century. Here and there an old house has been demolished, to be sure; even now you may see the work of destruction going on, as a new street is being cut through a time-honored block close to the old church. But in the main the old thoroughfares run hither and thither, seemingly at random, as of old, disclosing everywhere at their limits a sky-line of picturesque gables, and shut in by walls that often are almost canon-like in narrowness; while the heavy, b.u.t.tressed doors and the small, high-placed windows speak of a time when every house partook of the nature of the fortress.

The footway of the thoroughfares has no doubt vastly changed, for it is for the most part paved now--badly enough, to be sure, yet, after all, paved as no city was in the good old days when garbage filled the streets and cleanliness was an unknown virtue. The Jena streets of to-day are very modern in their cleanliness; yet a touch of medievalism is retained in that the main work of cleaning is done by women. But, for that matter, it seems to the casual observer as if the bulk of all the work here were performed by the supposedly weaker s.e.x. Certainly woman is here the chief beast of burden. In every direction she may be seen, in rustic garb, struggling cheerily along under the burden of a gigantic basket strapped at her back. You may see the like anywhere else in Germany, to be sure, but not often elsewhere in such preponderant numbers. And scarcely elsewhere does the sight jar so little on one's New-World sensibilities as in the midst of this mediaeval setting. One is even able to watch the old women sawing and splitting wood in the streets here, with no thought of anything but the picturesque-ness of the incident.

If one follows a band of basket-laden women, he will find that their goal is that focal-point of every old-time city, the market-place. There arrived, he will witness a scene common enough in Europe but hardly to be duplicated anywhere in America. Hundreds of venders of meat, fish, vegetables, cloths, and household utensils have their open-air booths scattered all across the wide s.p.a.ce, and other hundreds of purchasers are there as well. Quaint garbs and quainter faces are everywhere, and the whole seems quite in keeping with the background of fifteenth-century houses that hedges it in on every side. Could John the Magnanimous, who rises up in bronze in the midst of the a.s.sembly, come to life, he would never guess that three and a half centuries have pa.s.sed since he fell into his last sleep.

This same John the Magnanimous it was who founded the inst.i.tution which gives Jena its fame and distinguishes it from all the other quaint hypnotic cl.u.s.ters of houses that nestle similarly here and there in other picturesque valleys of the Fatherland--I mean, of course, its world-renowned university. It is but a few minutes' walk from the market-place, past the home where Schiller once lived and through the "street" scarcely more than arms'-breadth wide beyond, to the site of the older buildings of the university. Inornate, prosaic buildings they are, unrelieved even by the dominant note of picturesqueness; rescued, however, from all suggestion of the commonplace by the rugged ruins of the famed "powder-tower" jutting out from the crest of the hill just above, by the spire of the old church which seems to rise from the oldest university building itself, and by the mountain peaks that jut up into view far beyond.

If you would enter one of the old buildings there is naught to hinder.

Go into one of the lecture-halls which chances at the moment to be unoccupied, and you will see an array of crude old benches for seats that look as if they might have been placed there at the very inaugural of the inst.i.tution. The boards that serve for desks, if you scan them closer, you will find scarred all over with the marks of knives, showing how some hundreds of successive cla.s.ses of listeners have whiled away the weary lecture-hours. Not a square inch can you find of the entire desk surface that is un-scarred. If one would woo a new sensation, he has but to seat himself on one of these puritanical old benches and conjure up in imagination the long series of professors that may have occupied the raised platform in front, recalling the manner of thought and dogma that each laid down as verity. He of the first series appears in the garb of the sixteenth century, with mind just eagerly striving to peer a little way out of the penumbra of the Renaissance. The students who carve the first gashes in the new desks will learn, if perchance they listen in intervals of whittling, that this World on which they live is perhaps not flat, but actually round, like a ball. It is debatable doctrine, to be sure, but we must not forget that Signor Columbus, recently dead, found land off to the west which is probably a part of the Asiatic continent. If the earth be indeed a ball, then the sun and stars whirl clear around it in twenty-four hours, travelling thus at an astonishing speed, for the sphere in which they are fastened is situated hundreds of miles away. The sun must be a really great ball of fire--perhaps a mile even in diameter. The moon, as is plain to see, is nearly as large. The stars, of course, are only sparks, though of great brilliancy. They are fixed in a different sphere from that of the sun. In still other spheres are the moon, and a small set of large stars called planets, of which latter there are four, in order that, with the sun, the moon, and the other stars, there may be made seven orders of heavenly bodies--seven being, of course, the magic number in accordance with which the universe is planned.

This is, in substance, the whole subject of astronomy, as that first professor must have taught it, even were he the wisest man of his time.

Of the other sciences, except an elementary mathematics, there was hardly so much as an inkling taught that first cla.s.s of students. You will find it appalling, as you muse, to reflect upon the amazing mixture of utter ignorance and false knowledge which the learned professor of that day brought to the cla.s.s-room, and which the "educated" student carried away along with his degree. The one and the other knew Greek, Latin, and Bible history and doctrine. Beyond that their minds were as the minds of babes. Yet no doubt the student who went out from the University of Jena in the year 1550 thought himself upon the pinnacles of learning. So he was in his day and age, but could he come to life to-day, in the full flush of his scholarship, yonder wood-vender, plying her saw out here in front of the university building, would laugh in derision at his simplicity and ignorance. So it seems that, after all, the subjects of John the Magnanimous have changed more than a little during the three hundred and odd years that John himself, done in bronze, has been standing out there in the market-place.

THE CAREER OF A ZOOLOGIST

Had one time for it, there would be real interest in noting the steps by which the mental change in question has been brought about; in particular to note the share which the successive generations of Jena professors have taken in the great upward struggle. But we must not pause for that here. Our real concern, despite the haunting reminiscences, is not with the Jena of the past, but with the Jena of to-day; not with ghosts, but with the living personality who has made the Jena of our generation one of the greatest centres of progress in human thought in all the world. Jena is Jena to-day not so much because Guericke and Fichte and Hegel and Schiller and Oken taught here in the past, as because it has for thirty-eight years been the seat of the labors of Germany's greatest naturalist, one of the most philosophical zoologists of any country or any age, Professor Ernst Haeckel. It is of Professor Haeckel and his work that I chiefly mean to write, and if I have dwelt somewhat upon Jena itself, it is because this quaint, retired village has been the theatre of Haeckel's activities all the mature years of his life, and because the work he has here accomplished could hardly have been done so well elsewhere; some of it, for reasons I shall presently mention, could hardly have been done elsewhere at all--at least in another university.

It was in 1861 that young Dr. Haeckel came first to Jena as a teacher.

He had made a tentative effort at the practice of medicine in Berlin, then very gladly had turned from a distasteful pursuit to the field of pure science. His first love, before he took up the study of medicine, had been botany, though pictorial art, then as later, competed with science for his favorable attention. But the influence of his great teacher, Johannes Muller, together with his medical studies, had turned his attention more directly to the animal rather than vegetable life, and when he left medicine it was to turn explicitly to zoology as a life study. Here he believed he should find a wider field than in art, which he loved almost as well, and which, it may be added, he has followed all his life as a dilettante of much more than amateurish skill. Had he so elected, Haeckel might have made his mark in art quite as definitely as he has made it in science. Indeed, even as the case stands, his draughtsman's skill has been more than a mere recreation to him, for without his beautiful drawings, often made and reproduced in color, his cla.s.sical monographs on various orders of living creatures would have lacked much of their present value.

Moreover, quite aside from these merely technical drawings, Professor Haeckel has made hundreds of paintings purely for recreation and the love of it, ill.u.s.trating--and that too often with true artistic feeling for both form and color--the various lands to which his zoological quests have carried him, such as Sicily, the Canaries, Egypt, and India.

From India alone, after a four-months' visit, Professor Haeckel brought back two hundred fair-sized water-colors, a feat which speaks at once for his love of art and his amazing industry.

I dwell upon this phase of Professor Haeckel's character and temperament from the very outset because I wish it constantly to be borne in mind, in connection with some of the doctrines to be mentioned presently, that here we have to do with no dry-as-dust scientist, cold and soulless, but with a broad, versatile, imaginative mind, one that links the scientific and the artistic temperaments in rarest measure. Charles Darwin, with whose name the name of Haeckel will always be linked, told with regret that in his later years he had become so steeped in scientific facts that he had lost all love for or appreciation of art or music. There has been no such mental warping and atrophy in the mind of Ernst Haeckel.

Yet there is probably no man living to-day whose mind contains a larger store of technical scientific facts than his, nor a man who has enriched zoology with a larger number of new data, the result of direct personal observation in field or laboratory.

How large Haeckel's contribution in this last regard has been can be but vaguely appreciated by running over the long list of his important publications, though the list includes more than one hundred t.i.tles, unless it is understood that some single t.i.tles stand for monographs of gigantic proportions, which have involved years of labor in the production. Thus the text alone of the monograph on the radiolarians, a form of microscopic sea-animalcule (to say nothing of the volume of plates), is a work of three gigantic volumes, weighing, as Professor Haeckel laughingly remarks, some thirty pounds, and representing twelve years of hard labor. This particular monograph, by-the-bye, is written in English (of which, as of several other languages, Professor Haeckel is perfect master), and has a history of more than ordinary interest. It appears that the radiolarians were discovered about a half-century ago by Johannes Muller, who made an especial-study of them, which was uncompleted at the time of his death in 1858. His monograph, describing the fifty species then known, was published posthumously. Haeckel, on whom the mantle of the great teacher was to fall, and who had been Muller's last pupil, took up the work his revered master had left unfinished as his own first great original _Arbeit_. He went to Messina and was delighted to find the sea there replete with radiolarians, of which he was able to discover one or two new species almost every day, until he had added one hundred and fifty all told to Muller's list, or more than triple the whole number previously known. The description of these one hundred and fifty new radiolarians const.i.tuted Haeckel's first great contribution to zoology, and won him his place as teacher at Jena in 1861.

Henceforth Haeckel was, of course, known as the greatest authority on this particular order of creatures. For this reason it was that Professor Murray, the naturalist of the famous expedition which the British government sent around the world in the ship _Challenger_, asked Haeckel to work up the radiolarian material that had been gathered during that voyage. Murray showed Haeckel a little bottle containing water, with a deposit of seeming clay or mud in the bottom. "That mud," he said, "was dredged up from the bottom of the ocean, and every particle of it is the sh.e.l.l of a radiolarian." "Impossible," said Haeckel. "Yet true," replied Murray, "as the microscope will soon prove to you."

So it did, and Professor Haeckel spent twelve years examining that mud under the microscope, with the result that, before he had done, he had discovered no fewer than four thousand new species of radiolarians, all of which, of course, had to be figured, described, and christened.

Think of baptizing four thousand creatures, finding a new, distinct, and appropriate Latin name for each and every one, and that, too, when the creatures themselves are of microscopic size, and the difference between them often so slight that only the expert eye could detect it. Think, too, of the deadly tedium of labor in detecting these differences, in sketching them, and in writing out, to the length of three monster volumes, technical dissertations upon them.

To the untechnical reader that must seem a deadly, a veritably mind-sapping task. And such, indeed, it would prove to the average zoologist. But with the mind of a Haeckel it is far otherwise. To him a radiolarian, or any other creature, is of interest, not so much on its own account as for its a.s.sociations. He sees it not as an individual but as a link in the scale of organic things, as the bearer of a certain message of world-history. Thus the radiolarians, insignificant creatures though they seem, have really taken an extraordinary share in building up the crust of the earth. The ooze at the bottom of the sea, which finally becomes metamorphosed into chalk or stone, is but the aggregation of the sh.e.l.ls of dead radiolarians. In the light of such a role the animalcule takes on a new interest.

But even greater is the interest that attaches to every creature in regard to the question of its place in the organic scale of evolution.

What are the h.o.m.ologies of this form and that? What its probable ancestry? What gaps does it bridge? What can it tell us of the story of animal creation? These and such like are the questions that have been ceaselessly before Haeckel's mind in all his studies of zoology. Hence the rich fountain of philosophical knowledge that has welled up from what otherwise might have been the most barren of laboratory borings.

Thus from a careful investigation of the sponge Haeckel was led to his famous gastrula theory, according to which the pouchlike sponge-animalcule--virtually a stomach without members--is the type of organism on which all high organisms are built, so to speak--that is, out of which all have evolved.

This gastrula theory, now generally accepted, is one of Haeckel's two great fundamental contributions to the evolution philosophy with the history of which his life work is so intimately linked. The other contribution is the theory, even more famous and now equally undisputed, that every individual organism, in its em-bryological development, rehea.r.s.es in slurred but unmistakable epitome the steps of evolution by which the ancestors of that individual came into racial being. That is to say, every mammal, for example, originating in an egg stage, when it is comparable to a protozoon, pa.s.ses through successive stages when it is virtually in succession a gastrula, a fish, and an amphibian before it attains the mammalian status, because its direct ancestors were in succession, through the long geological ages, protozoons, gastrulae, fishes, amphibians before the true mammal was evolved. This theory cast a flood of light into many dark places of the Darwinian philosophy. It was propounded in 1866 in Professor Haeckel's great work on morphology, and it has ever since been a guiding principle in his important philosophical studies.

It was through this same work on morphology that Haeckel first came to be universally recognized as the great continental champion of Darwinism--the Huxley of Germany. Like Huxley, Haeckel had at once made the logical application of the Darwinian theory to man himself, and he sought now to trace the exact lineage of the human family as no one had hitherto attempted to fathom it. Utilizing his wide range of zoological and anatomical knowledge, he constructed a hypothetical tree of descent--or, if you prefer, ascent--from the root in a protozoon to the topmost twig or most recent offshoot, man. From that day till this Haeckel's persistent labors have been directed towards the perfection of that genealogical tree.

This work on morphology was much too technical to reach the general public, but in 1868 Haeckel prepared, at the instigation of his friend and confrere Gagenbaur, what was practically a popular abridgment of the technical work, which was published under the t.i.tle of _The Natural History of Creation_. This work created a furor at once. It has been translated into a dozen languages, and has pa.s.sed through nine editions in the original German. Through it the name of Haeckel became almost a household word the world over, and subject for mingled applause and opprobrium--applause from the unprejudiced for its great merit; opprobrium from the bigoted because of the unprecedented candor with which it followed the Darwinian hypothesis to its logical goal.

The same complete candor of expression has marked every stage of the unfolding of Professor Haeckel's philosophical p.r.o.nouncements. This fact is the more remarkable because Professor Haeckel is, so far as I am aware, the only scientist of our generation who has felt at liberty to announce, absolutely without reserve, the full conclusions to which his philosophy has carried him, when these conclusions ran counter to the prevalent prejudices of his time. Some one has said that the German universities are oases of freedom. The remark is absolutely true of Jena. It is not true, I believe, in anything like the same degree of any other German university, or of any other university in the world. One thing before others that has endeared Jena to Haeckel, and kept him there in the face of repeated flattering calls to other universities, is that full liberty of spirit has been accorded him there, as he knew it would not be accorded elsewhere. "When a man comes into the atmosphere of Jena," says Professor Haeckel, "he perforce begins to think--there is no escape from it. And he is free to let his thoughts carry him whithersoever they honestly may. My beliefs," he added, "are substantially the beliefs of my colleagues in science everywhere, as I know from private conversations; but they, unlike myself, are not free to speak the full truth as they see it. I myself would not be tolerated elsewhere, as I am well aware. Had I desired to remain in Berlin, for example, I must have kept silent. But here in Jena one is free."

And he smiles benignly as he says it. The controversies through which he has pa.s.sed and the calumnies of which he has been the target have left no scars upon this broad, calm spirit.

HAECKEL AS MAN AND TEACHER

It is indeed a delightful experience to meet Professor Haeckel in the midst of his charming oasis of freedom, his beloved Jena. To reach his laboratory you walk down a narrow lane, past Schiller's house, and the garden where Schiller and Goethe used to sit and where now the new observatory stands. Haeckel's laboratory itself is a simple oblong building of yellowish brick, standing on a jutting point of land high above the street-level. Entering it, your eye is first caught by a set of simple panels in the wall opposite the door bearing six ill.u.s.trious names: Aristotle, Linne, Lamarck, Cuvier, Muller, Darwin--a Greek, a Swede, two Frenchmen, a German, and an Englishman. Such a list is significant; it tells of the cosmopolitan spirit that here holds sway.

The ground-floor of the building is occupied by a lecture-room and by the zoological collection. The latter is a good working-collection, and purports to be nothing else. Of course it does not for a moment compare with the collections of the museums in any large city of Europe or America, nor indeed is it numerically comparable with many private collections, or collections of lesser colleges in America. Similarly, when one mounts the stairs and enters the laboratory proper, he finds a room of no great dimensions and nowise startling in its appointments. It is admirably lighted, to be sure, and in all respects suitably equipped for its purpose, but it is by no means so large or so luxurious as the average college laboratory of America. Indeed, it is not to be mentioned in the same breath with the laboratories of a score or two of our larger colleges. Yet, with Haeckel here, it is unquestionably the finest laboratory in which to study zoology that exists in the world to-day, or has existed for the last third of a century.

Haeckel himself is domiciled, when not instructing his cla.s.ses, in a comfortable but plain room across the hall--a room whose windows look out across the valley of the Saale on an exquisite mountain landscape, with the clear-cut mountain that Schiller's lines made famous at its focus. As you enter the room a big, robust man steps quickly forward to grasp your hand. Six feet or more in height, compactly built, without corpulence; erect, vigorous, even athletic; with florid complexion and clear, laughing, light-blue eyes that belie the white hair and whitening beard; the ensemble personifying at once kindliness and virility, simplicity and depth, above all, frank, fearless honesty, without a trace of pose or affectation--such is Ernst Haeckel. There is something about his simple, frank, earnest, sympathetic, yet robust, masculine personality that reminds one instinctively, as does his facial contour also, of Walt Whitman.

A glance about the room shows you at once that it is a place for study, and also that it is the room of the most methodical of students.

There are books and papers everywhere, yet not the slightest trace of disorder. Clearly every book and every parcel of papers has a place, and is kept in that place. The owner can at any moment lay his hand upon anything he desires among all these doc.u.ments. This habit of orderliness has had no small share, I take it, in contributing to Professor Haeckel's success in carrying forward many lines of research at the same time, and carrying all to successful terminations. Then there goes with it, as a natural accompaniment, a methodical habit of working, without which no single man could have put behind him the multifarious accomplishments that stand to Professor Haeckers credit.

Orderliness is not a more p.r.o.nounced innate gift with Professor Haeckel than is the gift of initial energy to undertake and carry on work which leads to accomplishment--a trait regarding which men, even active men, so widely differ. But Professor Haeckel holds that whatever his normal bent in this direction, it was enormously strengthened in boyhood by the precepts of his mother--from whom, by-the-bye, he chiefly inherits his talents. "My mother," he says, "would never permit me to be idle for a moment. If I stood at a window day-dreaming, she would always urge me to be up and doing. 'Work or play,' she would urge, 'but do not stand idle.' Through this reiterated admonition, physical activity became a life-long habit with me, and work almost a necessity of my being. If I have been able to accomplish my full share of labors, this is the reason. I am never idle, and I scarcely know the meaning of _ennui_."

This must not be interpreted as meaning, however, that Professor Haeckel takes up a task and works at it all day long unceasingly. That is not the German method of working, and in this regard Professor Haeckel is a thorough German. "When I was a young man," he says, "I at one time, thanks to the persuasions of some English friends, became a convert to the English method of working, and even attempted to introduce it into Germany. But I soon relinquished it, and lapsed back into our German method, which I am convinced will produce better results for the average worker. The essential of this method is the long midday rest, which enables one late in the afternoon to begin what is virtually a new day's-work, and carry it out with vigor and without undue fatigue.