Louis Agassiz: His Life and Correspondence Part 21

HUGH MILLER.

In the spring of 1850 Aga.s.siz married Elizabeth Cabot Cary, daughter of Thomas Graves Cary, of Boston. This marriage confirmed his resolve to remain, at least for the present, in the United States. It connected him by the closest ties with a large family circle, of which he was henceforth a beloved and honored member, and made him the brother-in-law of one of his most intimate friends in Cambridge, Professor C.C. Felton. Thus secure of favorable conditions for the care and education of his children, he called them to this country. His son (then a lad of fifteen years of age) had joined him the previous summer. His daughters, younger by several years than their brother, arrived the following autumn, and home built itself up again around him.

The various foreign members of his household had already scattered.

One or two had returned to Europe, others had settled here in permanent homes of their own. Among the latter were Professor Guyot and M. de Pourtales, who remained, both as scientific colleagues and personal friends, very near and dear to him all his life. "Papa Christinat" had also withdrawn. While Aga.s.siz was absent on a lecturing tour, the kind old man, knowing well the opposition he should meet, and wis.h.i.+ng to save both himself and his friend the pain of parting, stole away without warning and went to New Orleans, where he had obtained a place as pastor. This was a great disappointment to Aga.s.siz, who had urged him to make his home with him, a plan in which his wife and children cordially concurred, but which did not approve itself to the judgment of his old friend. M.

Christinat afterward returned to Switzerland, where he ended his days. He wrote constantly until his death, and was always kept advised of everything that pa.s.sed in the family at Cambridge. Of the old household, Mr. Burkhardt alone remained a permanent member of the new one.

CHAPTER 16.

1850-1852: AGE 43-45.

Proposition from Dr. Bache.

Exploration of Florida Reefs.

Letter to Humboldt concerning Work in America.

Appointment to Professors.h.i.+p of Medical College in Charleston, S.C.

Life at the South.

Views concerning Races of Men.

Prix Cuvier.

THE following letter from the Superintendent of the Coast Survey determined for Aga.s.siz the chief events of the winter of 1851.

FROM ALEXANDER DALLAS BACHE.

WEBB'S HILL, October 30, 1850.

MY DEAR FRIEND,

Would it be possible for you to devote six weeks or two months to the examination of the Florida reefs and keys in connection with their survey? It is extremely important to ascertain what they are and how formed. One account treats them as growing corals, another as ma.s.ses of something resembling oolite, piled together, barrier-wise. You see that this lies at the root of the progress of the reef, so important to navigation, of the use to be made of it in placing our signals, of the use as a foundation for light-houses, and of many other questions practically important and of high scientific interest. I would place a vessel at your disposal during the time you were on the reef, say six weeks.

The changes at or near Cape Florida, from the Atlantic coast and its siliceous sand, to the Florida coast and its coral sand, must be curious. You will be free to move from one end of the reef to the other, which will be, say one hundred and fifty miles. Motion to eastward would be slow in the windy season, though favored by the Gulf Stream as the winds are "trade." Whatever collections you might make would be your own. I would only ask for the survey such information and such specimens as would be valuable to its operations, especially to its hydrography, and some report on these matters. As this will, if your time and engagements permit, lead to a business arrangement, I must, though reluctantly, enter into that. I will put aside six hundred dollars for the two months, leaving you to pay your own expenses; or, if you prefer it, will pay all expenses of travel, including subsistence, to and from Key West, and furnish vessel and subsistence while there, and four hundred dollars.

What results would flow to science from your visit to that region!

You have spoken of the advantage of using our vessels when they were engaged in their own work. Now I offer you a vessel the motions of which you will control, and the a.s.sistance of the officers and crew of which you will have. You shall be at no expense for going and coming, or while there, and shall choose your own time. . .

Aga.s.siz accepted this proposal with delight, and at once made arrangements to take with him a draughtsman and an a.s.sistant, in order to give the expedition such a character as would make it useful to science in general, as well as to the special objects of the Coast Survey. It will be seen that Dr. Bache gladly concurred in all these views.

FROM ALEXANDER DALLAS BACHE.

WAs.h.i.+NGTON, December 18, 1850.

MY DEAR FRIEND,

On the basis of our former communications I have been, as the time served, raising a superstructure. I have arranged with Lieutenant Commander Alden to send the schooner W.A. Graham, belonging to the Coast Survey, under charge of an officer who will take an interest in promoting the great objects in which you will be engaged, to Key West, in time to meet you on your arrival in the Isabel of the 15th, from Charleston to Key West. The vessel will be placed at your absolute disposal for four to six weeks, as you may find desirable, doing just such things as you require, and going to such places as you direct. If you desire more than a general direction, I will give any specific ones which you may suggest. . .

I have requested that room be made in the cabin for you and for two aids, as you desire to take a draughtsman with you; and in reference to your enlarged plan of operating, of which I see the advantage, I have examined the financial question, and propose to add two hundred dollars to the six hundred in my letter of October 30th, to enable you to execute it. I would suggest that you stop a day in Was.h.i.+ngton on your way to Charleston, to pick up the topographical and geographical information which you desire, and to have all matters of a formal kind arranged to suit your convenience and wishes, which, I am sure, will all be promotive of the objects in view from your visit to Florida. . .You say I shall smile AT your plans,--instead of which, they have been smiled ON; now, there is a point for you,--a true Saxon distinction.

If you succeed (and did you ever fail!?) in developing for our Coast Survey the nature, structure, growth, and all that, of the Florida reefs, you will have conferred upon the country a priceless favor. . .

The Superintendent of the Coast Survey never had cause to regret the carte-blanche he had thus given. A few weeks, with the facilities so liberally afforded, gave Aga.s.siz a clew to all the phenomena he had been commissioned to examine, and enabled him to explain the relation between the keys and the outer and inner reefs, and the mud swamps, or more open channels, dividing them, and to connect these again with the hummocks and everglades of the main-land. It remains to be seen whether his theory will hold good, that the whole or the greater part of the Florida peninsula has, like its southern portion, been built up of concentric reefs. But his explanation of the present reefs, their structure, laws of growth, relations to each other and to the main-land, as well as to the Gulf Stream and its prevailing currents, was of great practical service to the Coast Survey. It was especially valuable in determining how far the soil now building up from acc.u.mulations of mud and coral debris was likely to remain for a long time s.h.i.+fting and uncertain, and how far and in what localities it might be relied upon as affording a stable foundation. When, at the meeting of the American a.s.sociation in the following spring, Aga.s.siz gave an account of his late exploration, Dr. Bache, who was present, said that for the first time he understood the bearing of the whole subject, though he had so long been trying to unravel it.

The following letter was written immediately after Aga.s.siz's return.

TO SIR CHARLES LYELL.

CAMBRIDGE, April 26, 1851.

. . .I have spent a large part of the winter in Florida, with a view of studying the coral reefs. I have found that they const.i.tute a new cla.s.s of reefs, distinct from those described by Darwin and Dana under the name of fringing reefs, barrier reefs, and atolls. I have lately read a paper upon that subject before the American Academy, which I shall send you as soon as it is printed. The case is this. There are several concentric reefs separated by deep channels; the peninsula of Florida itself is a succession of such reefs, the everglades being the filled-up channels, while the hummocks were formerly little intervening islands, like the mangrove islands in the present channels. But what is quite remarkable, all these concentric reefs are upon one level, above that of the sea, and there is no indication whatever of upheaval.

You will find some observations upon upheavals, etc., in Silliman, by Tuomey; it is a great mistake, as I shall show. The Tortugas are a real atoll, but formed without the remotest indication of subsidence.

Of course this does not interfere in the least with the views of Darwin, for the whole ground presents peculiar features. I wish you would tell him something about this. One of the most remarkable peculiarities of the rocks in the reefs of the Tortugas consists in their composition; they are chiefly made up of CORALLINES, limestone algae, and, to a small extent only, of real corals. . .

Aga.s.siz's report to the Coast Survey upon the results of this first investigation made by him upon the reefs of Florida was not published in full at the time. The parts practically most important to the Coast Survey were incorporated in their subsequent charts; the more general scientific results, as touching the physical history of the peninsula as a whole, appeared in various forms, were embodied in Aga.s.siz's lectures, and were printed some years after in his volume ent.i.tled "Methods of Study." The original report, with all the plates prepared for it, was published in the "Memoirs of the Museum of Comparative Zoology," under the supervision of Alexander Aga.s.siz, after the death of his father. It forms a quarto volume, containing some sixty pages of text, with twenty-two plates, ill.u.s.trative of corals and coral structure, and a map of Southern Florida with its reefs and keys.

This expedition was also of great importance to Aga.s.siz's collections, and to the embryo museum in Cambridge. It laid the foundation of a very complete collection of corals of all varieties and in all stages of growth. All the specimens, from huge coral heads and branching fans down to the most minute single corals, were given up to him, the value of the whole being greatly enhanced by the drawings taken on the spot from the living animals.

To this period belongs also the following fragment of a letter to Humboldt.

TO ALEXANDER VON HUMBOLDT.

[Probably 1852,--date not given.]

. . .What a time has pa.s.sed since my last letter! Had you not been constantly in my thoughts, and your counsels always before me as my guide, I should reproach myself for my silence. I hope my two papers on the medusae, forwarded this year, have reached you, and also one upon the cla.s.sification of insects, as based upon their development. I have devoted myself especially to the organization of the invertebrate animals, and to the facts bearing upon the perfecting of their cla.s.sification. I have succeeded in tracing the same ident.i.ty of structure between the three cla.s.ses of radiates, and also between those of mollusks, as has already been recognized in the vertebrates, and partially in the articulates. It is truly a pleasure for me now to be able to demonstrate in my lectures the insensible gradations existing between polyps, medusae, and echinoderms, and to designate by the same name organs seemingly so different. Especially has the minute examination of the thickness of the test in echinoderms revealed to me unexpected relations between the sea-urchin and the medusa. No one suspects, I fancy, at this moment, that the solid envelope of the Scutellae and the Clypeasters is traversed by a net-work of radiating tubes, corresponding to those of the medusae, so well presented by Ehrenberg in Aurelia aurita. If the Berlin zoologists will take the trouble to file off the surface of the test of an Echinarachnius parma, they will find a circular ca.n.a.l as large and as continuous as that of the medusae. The aquiferous tubes specified above open into this ca.n.a.l. But the same thing may be found under various modifications in other genera of the family. Since I have succeeded in injecting colored liquid into the beroids, for instance, and keeping them alive with it circulating in their transparent ma.s.s, I am able to show the ident.i.ty of their zones of locomotive fringes (combs), from which they take their name of Ctenophorae, with the ambulacral (locomotive) apparatus of the echinoderms. Furnished with these facts, it is not difficult to recognize true beroidal forms in the embryos of sea-urchins and star-fishes, published by Muller in his beautiful plates, and thus to trace the medusoid origin of the echinoderms, as the polypoid origin of the medusae has already been recognized. I do not here allude to their primitive origin, but simply to the general fact that among radiates the embryos of the higher cla.s.ses represent, in miniature, types of the lower cla.s.ses, as, for instance, those of the echinoderms resemble the medusae, those of the medusae the polyps.

Having pa.s.sed the greater part of last winter in Florida, where I was especially occupied in studying the coral reefs, I had the best opportunity in the world for prosecuting my embryological researches upon the stony corals. I detected relations among them which now enable me to determine the cla.s.sification of these animals according to their mode of development with greater completeness than ever before, and even to a.s.sign a superior or inferior rank to their different types, agreeing with their geological succession, as I have already done for the fishes. I am on the road to the same results for the mollusks and the articulates, and can even now say in general terms, that the most ancient representatives of all the families belonging to these great groups, strikingly recall the first phases in the embryonic development of their successors in more recent formations, and even that the embryos of comparatively recent families recall families belonging to ancient epochs. You will find some allusion to these results in my Lectures on Embryology, given in my "Lake Superior,"

of which I have twice sent you a copy, that it might reach you the more surely; but these first impressions have a.s.sumed greater coherence now, and I constantly find myself recurring to my fossils for light upon the embryonic forms I am studying and vice versa, consulting my embryological drawings in order to decipher the fossils with greater certainty.

The proximity of the sea and the ease with which I can visit any part of the coast within a range of some twenty degrees give me inexhaustible resources for the whole year, which, as time goes on, I turn more and more to the best account. On the other hand, the abundance and admirable state of preservation of the fossils found in our ancient deposits, as well as the regular succession of the beds containing them, contribute admirable material for this kind of comparative study. . .

In the summer of 1851 Aga.s.siz was invited to a professors.h.i.+p at the Medical College in Charleston, S.C. This was especially acceptable to him, because it subst.i.tuted a regular course of instruction to students, for the disconnected lectures given to miscellaneous audiences, in various parts of the country, by which he was obliged to eke out his small salary and provide for his scientific expenses. While more fatiguing than cla.s.s-room work, these scattered lectures had a less educational value, though, on the other hand, they awakened a very wide-spread interest in the study of nature. The strain of constant traveling for this purpose, the more hara.s.sing because so unfavorable to his habits of continuous work, had already told severely upon his health; and from this point of view also the new professors.h.i.+p was attractive, as promising a more quiet, though no less occupied, life. The lectures were to be given during the three winter months, thus occupying the interval between his autumn and spring courses at Cambridge.

He a.s.sumed his new duties at Charleston in December, 1851, and by the kindness of his friend Mrs. Rutledge, who offered him the use of her cottage for the purpose, he soon established a laboratory on Sullivan's Island, where the two or three a.s.sistants he had brought with him could work conveniently. The cottage stood within hearing of the wash of the waves, at the head of the long, hard sand beach which fringed the island sh.o.r.e for some three or four miles. There could hardly be a more favorable position for a naturalist, and there, in the midst of their specimens, Aga.s.siz and his band of workers might constantly be found. His studies here were of the greater interest to him because they connected themselves with his previous researches, not only upon the fishes, but also upon the lower marine animals of the coast of New England and of the Florida reefs; so that he had now a basis for comparison of the fauna scattered along the whole Atlantic coast of the United States. The following letter gives some idea of his work at this time.

TO PROFESSOR JAMES D. DANA.

CHARLESTON, January 26, 1852.

MY DEAR FRIEND,

You should at least know that I think of you often on these sh.o.r.es.

And how could I do otherwise when I daily find new small crustacea, which remind me of the important work you are now preparing on that subject.

Of course, of the larger ones there is nothing to be found after Professor Gibbes has gone over the ground, but among the lower orders there are a great many in store for a microscopic observer.

I have only to regret that I cannot apply myself more steadily. I find my nervous system so over-excited that any continuous exertion makes me feverish. So I go about as much as the weather allows, and gather materials for better times.

Several interesting medusae have been already observed; among others, the entire metamorphosis and alternate generation of a new species of my genus tiaropsis. You will be pleased to know that here, as well as at the North, tiaropsis is the medusa of a campanularia. Mr. Clark, one of my a.s.sistants, has made very good drawings of all its stages of growth, and of various other hydroid medusae peculiar to this coast. Mr. Stimpson, another very promising young naturalist, who has been connected with me for some time in the same capacity, draws the crustacea and bryozoa, of which there are also a good many new ones here. My son and my old friend Burkhardt are also with me (upon Sullivan's Island), and they look after the larger species, so that I shall probably have greatly increased my information upon the fauna of the Atlantic coast by the time I return to Cambridge.

In town, where I go three times a week to deliver lectures at the Medical College (beside a course just now in the evening also before a mixed audience), I have the rest of my family, so that nothing would be wanting to my happiness if my health were only better. . .What a pity that a man cannot work as much as he would like; or at least accomplish what he aims at. But no doubt it is best it should be so; there is no harm in being compelled by natural necessities to limit our ambition,--on the contrary, the better sides of our nature are thus not allowed to go to sleep.

However, I cannot but regret that I am unable at this time to trace more extensively subjects for which I should have ample opportunities here, as for instance the anatomy of the echinoderms, and also the embryology of the lower animals in general. . .

This winter, notwithstanding the limitations imposed upon his work by the state of his health, was a very happy one to Aga.s.siz. As mentioned in the above letter his wife and daughters had accompanied him to Charleston, and were established there in lodgings. Their holidays and occasional vacations were pa.s.sed at the house of Dr. John E. Holbrook (the "Hollow Tree"), an exquisitely pretty and picturesque country place in the neighborhood of Charleston. Here Aga.s.siz had been received almost as one of the family on his first visit to Charleston, shortly after his arrival in the United States. Dr. Holbrook's name, as the author of the "Herpetology of South Carolina," had long been familiar to him, and he now found a congenial and affectionate friend in the colleague and fellow-worker, whose personal acquaintance he had been anxious to make. Dr. Holbrook's wife, a direct descendant of John Rutledge of our revolutionary history, not only shared her husband's intellectual life, but had herself rare mental qualities, which had been developed by an unusually complete and efficient education. The wide and various range of her reading, the accuracy of her knowledge in matters of history and literature, and the charm of her conversation, made her a delightful companion. She exercised the most beneficent influence upon her large circle of young people, and without any effort to attract, she drew to herself whatever was most bright and clever in the society about her. The "Hollow Tree," presided over by its hospitable host and hostess was, therefore, the centre of a stimulating and cultivated social intercourse, free from all gene or formality. Here Aga.s.siz and his family spent many happy days during their southern sojourn of 1852. The woods were yellow with jessamine, and the low, deep piazza was shut in by vines and roses; the open windows and the soft air full of sweet, out-of-door fragrance made one forget, spite of the wood fire on the hearth, that it was winter by the calendar. The days, pa.s.sed almost wholly in the woods or on the veranda, closed with evenings spent not infrequently in discussions upon the scientific ideas and theories of the day, carried often beyond the region of demonstrated facts into that of speculative thought. An ever-recurring topic was that of the origin of the human race. It was Aga.s.siz's declared belief that man had sprung not from a common stock, but from various centres, and that the original circ.u.mscription of these primordial groups of the human family corresponded in a large and general way with the distribution of animals and their combination into faunae.