SIR NORMAN LOCKYER is professor of astronomical physics and director

of the solar observatory at the Royal College of Science in South

Kensington. Here it is that his chief work has been done for some thirty

years past. The foundation-stone of that work is spectroscopic study of

the sun and stars. In this study Professor Lockyer was a pioneer, and he

has for years been recognized as the leader. But he is no mere observer;

he is a generalizer as well; and he long since evolved revolutionary

ideas as to the origin of the sidereal and solar systems.

For a man whose chief occupation is the study of the sun and stars,

smoky, foggy, cloudy London may seem a strange location. I asked

Professor Lockyer about this, and his reply was most characteristic.

"The fact is," he said, "the weather here is too fine from one point of

view: my working staff is so small, and the number of working nights so

large, that most of the time there is no one about to do anything during

the day. Then, another thing, here at South Kensington I am in touch

with my colleagues in the other departments--physics, chemistry, and so

forth--and can at once draw upon their special knowledge for aid on any

obscure point in their lines that may crop up. If we were out in the

country this would not be so. You see, then, that it is a choice between

weather and brains. I prefer the brains."

Professor Lockyer went on to state, however, that he is by no means

altogether dependent upon the observations made at South Kensington. For

certain purposes the Royal Observatory at Greenwich is in requisition,

and there are three observatories at different places in India at which

photographs of the sun-spots and solar spectra are taken regularly.

From these combined sources photographs of the sun are forthcoming

practically every day of the year; to be accurate, on three hundred and

sixty days out of the three hundred and sixty-five. It was far

otherwise when Professor Lockyer first began his studies of the sun, as

observations were then made and recorded on only about one-third of the

days in each year.

Exteriorly the observatory at South Kensington is not at all such a

place as one might expect to find. It is, in Professor Lockyer's own

words, "little more than a collection of sheds," but within these

alleged sheds may be found an excellent equipment of telescopes, both

refracting and reflecting, and of all other things requisite to the

peculiar study which forms the subject of special research here.

I have had occasion again and again to call attention to this relatively

meagre equipment of the European institutions, but in no case, perhaps,

is the contrast more striking between the exterior appearance of a

famous scientific institution and the work that is being accomplished

within it than is shown in the case of the South Kensington observatory.

It should be added that this remark does not apply to the chief building

of the Royal College of Science itself.

The theories for which Professor Lockyer has so long been famous are

well known to every one who takes much interest in the progress of

scientific ideas. They are notably the theory that there is a direct

causal association between the prevalence of sun-spots and terrestrial

weather; the theory of the meteoritic origin of all members of the

sidereal family; and the dissociation theory of the elements, according

to which our so-called elements are really compounds, capable of being

dissociated into simpler forms when subjected to extreme temperatures,

such as pertain in many stars. As I have said, these theories are by no

means new. Professor Lockyer has made them familiar by expounding them

for a full quarter of a century or more. But if not new, these theories

are much too important to have been accepted at once without a protest

from the scientific world. In point of fact, each of them has been met

with most ardent opposition, and it would, perhaps, not be too much to

say that not one of them is, as yet, fully established. It is of the

highest interest to note, however, that the multitudinous observations

bearing upon each of these topics during the past decade have tended, in

Professor Lockyer's opinion, strongly to corroborate each one of these

opinions.

Two or three years ago Sir Norman Lockyer, in association with his son,

communicated to the Royal Society a paper in which the data recently

obtained as to the relation between sun-spots and the weather

in India--the field of observations having been confined to that

territory--are fully elaborated. A remarkable feature of the recent

work in that connection has been the proof, or seeming proof, that the

temperature of the sun fluctuates from year to year. At times when the

sun-spots are numerous and vigorous in their action, the spectrum of

the elements in these spots becomes changed. During the times of minimum

sun-spot activity the spectrum shows, for example, the presence of large

quantities of iron in these spots--of course in a state of vapor. But in

times of activity this iron disappears, and the lines which previously

vouched for it are replaced by other lines spoken of as the enhanced

lines of iron--that is to say, the lines which are believed to represent

the unknown substance or substances into which the iron has been

decomposed; and what is true of iron is true of various other elements

that are detected in the sun-spots. The explanation of this phenomena,

if Professor Lockyer reads the signs aright, is that during times of

minimum sun-spot activity the temperature of the sun-spots is relatively

cool, and that in times of activity the temperature becomes greatly

increased. One must come, therefore, to speaking of hot spots and cool

spots on the sun; although the cool spots, it will be understood,

would hardly be considered cool in the terrestrial sense, since their

temperature is sufficient to vaporize iron.

Now the point of the recent observations is that the fluctuations in

the sun's heat, due to the periodic increase and subsidence of sun-spot

disturbances--such fluctuations having been long recognized as having

regular cyclic intervals of about eleven years--are instrumental in

effecting changes in the terrestrial weather. According to the paper

just mentioned, it would appear to be demonstrated that the periods

of decreased rainfall in India have a direct and relatively unvarying

relationship to the prevalence of the sun-spots, and that, therefore, it

has now become possible, within reasonable limits, to predict some years

in advance the times of famine in India. So important a conclusion as

this is certainly not to be passed over lightly, and all the world,

scientific and unscientific alike, will certainly watch with acute

interest for the verification of this seemingly startling practical

result of so occult a science as solar spectroscopy.

The theory of the decomposition of the elements is closely bound up with

the meteoritic theory. In a word, it may be said of each that Professor

Lockyer is firmly convinced that all the evidence that has accumulated

in recent years is so strongly in favor as to bring these theories

almost to a demonstration. The essence of the meteoritic theory, it

will be recalled, is that all stars have their origin in nebulae which

consist essentially of clouds of relatively small meteorites. It will be

recalled further that Professor Lockyer long ago pointed out that

stars pass through a regular series of changes as to temperature, with

corresponding changes of structure, becoming for a time hotter and

hotter until a maximum is reached, and then passing through gradual

stages of cooling until their light dies out altogether. Very recently

Professor Lockyer has been enabled, through utilization of the multiform

records accumulated during years of study, to define the various typical

stages of the sidereal evolution; and not merely to define them but

to illustrate them practically by citing stars which belong to each

of these stages, and to give them yet clearer definition by naming the

various elements which the spectroscope reveals as present in each.

His studies have shown that the elements do not always give the same

spectrum under all conditions; a result quite at variance with the

earlier ideas on the subject. Even in the terrestrial laboratory it

is possible to subject various metals, including iron, to temperatures

attained with the electric spark at which the spectrum becomes different

from that, for example, which was attained with the lower temperature

of the electric arc. Through these studies so-called series-spectra

have been attained for various elements, and a comparison of these

series-spectra with the spectra of various stars has led to the

conclusion that many of the unknown lines previously traced in the

spectra of such stars are due to the decomposition products of familiar

elements; all of which, of course, is directly in line of proof of the

dissociation hypothesis.

Another important result of Professor Lockyer's very recent studies has

come about through observation of the sun in eclipse. A very interesting

point at issue all along has been the question as to what layers of the

sun's atmosphere are efficient in producing the so-called reverse lines

of the spectrum. It is now shown that the effect is not produced, as

formerly supposed, by the layers of the atmosphere lying just above the

region which Professor Lockyer long ago named the chromosphere, but by

the gases of higher regions. Reasoning from analogy, it may be supposed

that a corresponding layer of the atmosphere of other stars is the

one which gives us the reverse spectrum of those stars. The exact

composition of this layer of the sidereal atmosphere must, of course,

vary with the temperature of the different stars, but in no case can

we expect to receive from the spectroscope a full record of all the

substances that may be present in other layers of the atmosphere or in

the body of the star itself. Thus, for example, the ordinary Freuenhofer

spectrum of the sun shows us no trace of the element helium, though

through other observations at the time of eclipse Professor Lockyer had

discovered that element there, as we have seen, some thirty years before

anything was known of it on the earth.

In a recent eclipse photographs were taken of the spectra of the lower

part of the sun's atmosphere by itself, and it was found that the

spectrum of this restricted area taken by itself gave the lines which

specialize the spectra of so different a star as Procyon. "I recognize

in the result," says Professor Lockyer, "a veritable Rosetta Stone which

will enable us to read the celestial hieroglyphics presented to us in

stellar spectra, and help us to study the spectra and to get at results

much more distinctly and certainly than ever before."

But the most striking confirmation which the meteoritic hypothesis has

received has come to hand through study of the spectrum of the new star

which appeared in the constellation Perseus in February, 1901, and which

was so widely heralded everywhere in the public press. This star was

discovered on the morning of February 22d by star-gazers in Scotland,

and in America almost simultaneously. It had certainly not been

visible a few hours before, and it had blazed up suddenly to a greater

brilliancy than that of a first-magnitude star. At first it was

bluish-white in color, indicating an extremely high temperature, but

it rapidly subsided in brilliancy and assumed a red color as it cooled,

passing thus, in the course of a few days, through stages for which

ordinary stars require periods of many millions of years.

The most interesting feature of the spectrum of this new star was the

fact that it showed both light and dark lines for the same substances,

the two lying somewhat apart. This means, being interpreted, that some

portions of a given substance are giving out light, thus producing

the bright lines of the spectrum, and that other portions of the same

substance are stopping certain rays of transmitted light, thus producing

the dark lines. The space between the bright and dark lines, being

measured, indicated that there was a differential motion between the

two portions of substance thus recorded of something like seven hundred

miles a second. This means, according to theory--and it seems hardly

possible to explain it otherwise--that two sidereal masses, one at least

of which was moving at an enormous rate of speed, had collided, such

collision, of course, being the cause of the incandescence that made the

mass suddenly visible from the earth as a new star.

New stars are by no means every-day affairs, there having been but

thirty-two of them recorded in the world's history, and of these only

two have exceeded the present one in brilliancy. As a mere spectacle,

therefore, this new star was of great interest; but a far greater

importance attaches to it through the fact that it conforms so admirably

to the course that meteoritic hypothesis would predict for it. "That is

what confounds my opponents," said Professor Lockyer, in talking to me

about the new star. "Most of those who oppose my theory have not taken

the trouble to make observations for themselves, but have contented

themselves with falling back apparently on the postulate that because

a theory is new it must be wrong. Then, outside the scientific world,

comparatively few people appreciate the extreme parsimony of nature.

They expect, therefore, that when such a phenomenon as the appearance of

a new star occurs, the new-comer will establish new rules for itself and

bring chaos into the scientific world. But in point of fact nature never

does things in two ways if she can possibly do them in one, and the

most striking thing about the new stars is that all the phenomena they

present conform so admirably to the laws built up through observation of

the old familiar stars. As to our particular theories, we here at South

Kensington"--it will be understood that this use of the editorial "we"

is merely a modest subterfuge on the part of Professor Lockyer--"have

no regard for them at all simply as ours. Like all scientists worthy the

name, we seek only the truth, and should new facts come along that seem

to antagonize our theory we should welcome them as eagerly as we welcome

all new facts of whatever bearing. But the truth is that no such new

facts have appeared in all these years, but that, on the contrary, the

meteoritic hypothesis has received ever-increasing support from most

unexpected sources, from none more brilliantly or more convincingly than

from this new star in Perseus." And I suspect that as much as this at

least--if not indeed a good deal more--will be freely admitted by every

candid investigator of Sir Norman Lockyer's theory.

SIR WILLIAM RAMSAY AND THE NEW GASES

The seat of Sir William Ramsay's labors is the University College,

London. The college building itself, which is located on Gower Street,

is, like the British Museum, reminiscent or rather frankly duplicatory

in its columned architecture of the classical. Interiorly it is like

so many other European institutions in its relative simplicity of

equipment. One finds, for example, Professor Ramsay and Dr. Travers

generating the hydrogen for their wonderful experiments in an old

beer-cask. Professor Ramsay himself is a tall, rather spare man, just

entering the gray stage of life, with the earnest visage of the scholar,

the keen, piercing eye of the investigator--yet not without a twinkle

that justifies the lineage of the "canny Scot." He is approachable,

affable, genial, full of enthusiasm for his work, yet not taking it with

such undue seriousness as to rob him of human interest--in a word, the

type of a man of science as one would picture him in imagination, and

would hope, with confident expectation, to find him in reality.

I have said that the equipment of the college is somewhat primitive, but

this must not be taken too comprehensively. Such instances as that

of the beer-cask show, to be sure, an adaptation of means to ends on

economical lines; yet, on the other hand, it should not be forgotten

that the beer-cask serves its purpose admirably; and, in a word, it may

be said that Professor Ramsay's laboratory contains everything that

is needed to equip it fully for the special work to which it has been

dedicated for some years past. In general, it looks like any other

laboratory--glass tubes, Bunsen burners, retorts and jars being in

more or less meaningless tangles; but there are two or three bits of

apparatus pretty sure to attract the eye of the casual visitor which

deserve special mention. One of these is a long, wooden, troughlike

box which extends across the room near the ceiling and is accessible by

means of steps and a platform at one end. Through this boxlike tube the

chief expert in spectroscopy (Dr. Bay-ley) spies on the spectrum of

the gas, and learns some of its innermost secrets. But an even more

mystifying apparatus is an elaborate array of long glass tubes, some of

them carried to the height of several feet, interspersed with cups of

mercury and with thermometers of various sizes and shapes. The technical

scientist would not make much of this description, but neither would an

untechnical observer make much of the apparatus; yet to Dr. Travers, its

inventor, it is capable of revealing such extraordinary things as the

temperature of liquid hydrogen--a temperature far below that at which

the contents of even an alcoholic thermometer are solidified; at which,

indeed, the prime constituents of the air suffer a like fate. The

responsible substance which plays the part of the familiar mercury, or

alcohol, in Dr. Travers's marvellous thermometer is hydrogen gas.

The principle by which it is utilized does not differ, in its rough

essentials, from that of ordinary thermometers, but the details of its

construction are much too intricate to be elaborated here.

But if you would see the most wonderful things in this laboratory--or

rather, to be quite accurate, I should say, if you would stand in the

presence of the most wonderful things--you must go with Professor

Ramsay to his own private laboratory, and be introduced to some little

test-tubes that stand inverted in cups of mercury decorating a shelf at

one end. You would never notice these tubes of your own accord were

you to browse ever so long about the room. Even when your attention

is called to them you still see nothing remarkable. These are ordinary

test-tubes inverted over ordinary mercury. They contain something, since

the mercury does not rise in them completely, but if that something be

other than ordinary air there is nothing about its appearance, or rather

lack of appearance, to demonstrate it. But your interest will hardly

fail to be arrested when Professor Ramsay, indicating one and another of

these little tubes, says: "Here you see, or fail to see, all the krypton

that has ever been in isolated existence in the world, and here all the

neon, and here, again, all the zenon."

You will understand, of course, that krypton, neon, and zenon are the

new gases of the atmosphere whose existence no one suspected until

Professor Ramsay ferreted them out a few years ago and isolated them. In

one sense there should be nothing mysterious about substances that every

air-breathing creature on the globe has been imbibing pretty constantly

ever since lungs came into fashion. But in another view the universal

presence of these gases in the air makes it seem all the more wonderful

that they could so long have evaded detection, considering that

chemistry has been a precise science for more than a century. During

that time thousands of chemists have made millions of experiments in the

very midst of these atmospheric gases, yet not one of the experimenters,

until recently, suspected their existence. This proves that these gases

are no ordinary substances--common though they be. Personally I have

examined many scientific exhibits in many lands, but nowhere have I seen

anything that filled my imagination with so many scientific visions as

these little harmless test-tubes at the back of Professor Ramsay's desk.

Perhaps I shall attempt to visualize some of these imaginings before

finishing this paper, but for the moment I wish to speak of the _modus

operandi_ of the discovery of these additions to the list of elements.

The discovery of argon came about in a rather singular way. Lord

Rayleigh, of the Royal Institution, had noticed in experiments with

nitrogen that when samples of this element were obtained from chemicals,

such samples were uniformly about one per cent, lighter in weight

than similar quantities of nitrogen obtained from the atmosphere.

This discrepancy led him to believe that the atmospheric nitrogen must

contain some impurity.

Curiously enough, the experiments of Cavendish, the discoverer of

nitrogen--experiments made more than a century ago--had seemed to show

quite conclusively that some gaseous substance different from nitrogen

was to be found mixed with the samples of this gas as he obtained it

from the atmosphere. This conclusion of Cavendish, put forward indeed

but tentatively, had been quite ignored by his successors. Now,

however, it transpired, by experiments made jointly by Lord Rayleigh

and Professor Ramsay, that the conclusion was quite justified, it being

shown presently that there actually exists in every portion of nitrogen,

as extracted from the atmosphere, a certain quantity of another gas,

hitherto unknown, and which now received the name of argon. It will

be recalled with what astonishment the scientific and the unscientific

world alike received the announcement made to the Royal Society in 1895

of the discovery of argon, and the proof that this hitherto unsuspected

constituent of the atmosphere really constitutes about one per cent, of

the bulk of atmospheric nitrogen, as previously estimated.

The discovery here on the earth of a substance which Professor Lockyer

had detected as early as 1868 in the sun, and which he had provisionally

named helium, excited almost equal interest; but this element was found

in certain minerals, and not as a constituent of the atmosphere.

Having discovered so interesting a substance as argon, Professor

Ramsay and his assistants naturally devoted much time and attention to

elucidating the peculiarities of the new substance. In the course of

these studies it became evident to them that the presence of argon alone

did not fully account for all the phenomena they observed in handling

liquefied air, and in 1898 Professor Ramsay was again able to electrify

his audience at the Royal Society by the announcement of the discovery,

in pretty rapid succession, of three other elementary substances as

constituents of the atmosphere, these three being the ones just referred

to--krypton, neon, and zenon.

It is a really thrilling experience, standing in the presence of the

only portions of these new substances that have been isolated, to hear

Professor Ramsay and Dr. Travers, his chief assistant, tell the story

of the discovery--how they worked more and more eagerly as they found

themselves, so to say, on a "warmer scent," following out this clew

and that until the right one at last brought the chase to a successful

issue. "It was on a Sabbath morning in June, if I remember rightly,

when we finally ran zenon down," says Dr. Travers, with a half smile;

and Professor Ramsay, his eyes twinkling at the recollection of this

very unorthodox procedure, nods assent. "And have you got them all

now?" I queried, after hearing the story. "Yes; we think so," replied

Professor Ramsay. "And I am rather glad of it," he adds, with a half

sigh, "for it was wearisome even though fascinating work." Just how

wearisome it must have been only a professional scientific investigator

can fully comprehend; but the fascination of it all may be comprehended

in some measure by every one who has ever attempted creative work of

whatever grade or in whatever field.

I have just said that the little test-tubes contain the only bit of

each of the substances named that has ever been isolated. This statement

might lead the untechnical reader to suppose that these substances, once

isolated, have been carefully stored away and jealously guarded, each

in its imprisoning test-tubes. Jealously guarded they have been, to be

sure, but there has not been, by any means, the solitary confinement

that the words might seem to imply. On the contrary, each little whiff

of gas has been subjected to a variety of experiments--made to pass

through torturing-tubes under varying conditions of temperature, and

brought purposely in contact with various other substances, that its

physical and chemical properties might be tested. But in each case the

experiment ended with the return of the substance, as pure as before, to

its proper tube. The precise results of all these experiments have been

communicated to the Royal Society by Professor Ramsay. Most of these

results are of a technical character, hardly appealing to the average

reader. There is one very salient point, however, in regard to which all

the new substances, including argon and helium, agree; and it is that

each of them seems to be, so far as present experiments go, absolutely

devoid of that fundamental chemical property, the power to combine with

other elements. All of them are believed to be monatomic--that is

to say, each of their molecules is composed of a single atom. This,

however, is not an absolutely novel feature as compared with other

terrestrial elements, for the same thing is true, for example, of such a

familiar substance as mercury. But the incapacity to enter into chemical

combinations seems very paradoxical; indeed it is almost like saying

that these are chemical elements which lack the most fundamental of

chemical properties.

It is this lack of combining power, of course, that explains the

non-discovery of these elements during all these years, for the

usual way of testing an element is to bring it in contact with other

substances under conditions that permit its atoms to combine with

other atoms to the formation of new substances. But in the case of new

elements such experiments as this have not proved possible under any

conditions as yet attained, and reliance must be had upon other physical

tests--such as variation of the bulk of the gas under pressure, and

under varying temperatures, and a study of the critical temperatures

and pressures under which each gas becomes a liquid. The chief reliance,

however, is the spectroscope--the instrument which revealed the presence

of helium in the sun and the stars more than a quarter of a century

before Professor Ramsay ferreted it out as a terrestrial element.

Each whiff of colorless gas in its test-tube interferes with the light

passing through it in such a way that when viewed through a prism it

gives a spectrum of altogether unique lines, which stamp it as krypton,

neon, or zenon as definitely as certain familiar and more tangible

properties stamp the liquid which imprisons it as mercury.

QUERIES SUGGESTED BY THE NEW GASES

Suppose that a few years ago you had asked some chemist, "What are the

constituents of the atmosphere?" He would have responded, with entire

confidence, "Oxygen and nitrogen chiefly, with a certain amount of

water-vapor and of carbonic-acid gas and a trace of ammonia." If

questioned as to the chief properties of these constituents, he would

have replied, with equal facility, that these are among the most

important elements; that oxygen might almost be said to be the

life-giving principle, inasmuch as no air-breathing creature could get

along without it for many moments together; and that nitrogen is equally

important to the organism, though in a different way, inasmuch as it is

not taken up through the lungs. As to the water-vapor, that, of course,

is a compound of oxygen and hydrogen, and no one need be told of its

importance, as every one knows that water makes up the chief bulk of

protoplasm; carbonic-acid gas is also a compound of oxygen, the other

element this time being carbon, and it plays a quite different rôle in

the economy of the living organism, inasmuch as it is produced by the

breaking down of tissues, and must be constantly exhaled from the lungs

to prevent the poisoning of the organism by its accumulation; while

ammonia, which exists only in infinitesimal quantities in the air, is a

compound of nitrogen and hydrogen, introducing, therefore, no new

element.

If one studies somewhat attentively the relation which these elements

composing the atmosphere bear to the living organism he cannot fail to

be struck with it; and it would seem a safe inductive reasoning from the

stand-point of the evolutionist that the constituents of the atmosphere

have come to be all-essential to the living organism, precisely because

all their components are universally present. But, on the other hand,

if we consider the matter in the light of these researches regarding the

new gases, it becomes clear that perhaps the last word has not been said

on this subject; for here are four or five other elementary substances

which, if far less abundant than oxygen and nitrogen, are no less widely

distributed and universally present in the atmosphere, yet no one of

which apparently takes any chemical share whatever in ministering to the

needs of the living organism. This surely is an enigma.

Taking another point of view, let us try to imagine the real status of

these new gases of the air. We think of argon as connected with nitrogen

because in isolation experiments it remains after the oxygen has been

exhausted, but in point of fact there is no such connection between

argon and nitrogen in nature. The argon atom is just as closely in

contact with the oxygen in the atmosphere as with the nitrogen; it

simply repels each indiscriminately. But consider a little further;

the argon atom not only repels all advance on the part of oxygen and

nitrogen, but it equally holds itself aloof from its own particular

kindred atoms. The oxygen or nitrogen atom never rests until it has

sought out a fellow, but the argon atom declines all fellowship. When

the chemist has played his tricks upon it, it finds itself crowded

together with other atoms of the same kind; but lift up the little

test-tube and these scurry off from one another in every direction, each

losing its fellows forever as quickly as possible.

As one ponders this one is almost disposed to suggest that the atom of

argon (or of krypton, helium, neon, or zenon, for the same thing applies

to each and all of these) seems the most perfect thing known to us in

the world, for it needs no companionship, it is self-sufficing. There

is something sublime about this magnificient isolation, this splendid

self-reliance, this undaunted and undauntable self-sufficiency--these

are traits which the world is wont to ascribe to beings more than

mortal. But let us pause lest we push too far into the old, discredited

territory of metaphysics.

PROFESSOR J. J. THOMPSON AND THE NATURE OP ELECTRICITY

Many fascinating questions suggest themselves in connection with these

strange, new elements--new, of course, only in the sense of human

knowledge--which all these centuries have been about us, yet which have

managed until now to keep themselves as invisible and as intangible as

spirits. Have these celibate atoms remained thus always isolated, taking

no part in world-building? Are they destined throughout the sweep of

time to keep up this celibate existence? And why do these elements alone

refuse all fellowship, while the atoms of all the other seventy-odd

known elements seek out mates under proper conditions with unvarying

avidity?

It is perhaps not possible fully to answer these questions as yet, but

recent studies in somewhat divergent fields give us suggestive clews to

some of them. I refer in particular to the studies in reference to the

passage of electricity through liquids and gases and to the observations

on radioactivity. The most conspicuous worker in the field of

electricity is Professor J. J. Thompson, who for many years has had

charge of the Cavendish laboratory at Cambridge. In briefly reviewing

certain phases of his work we shall find ourselves brought into contact

with some of the same problems raised by workers in the other fields of

physics, and shall secure some very interesting bits of testimony as to

the solution of questions already outlined.

The line of observation which has led to the most striking results has

to do, as already suggested, with the conduction of electricity through

liquids and gases. It has long been known that many liquids conduct

electricity with relative facility. More recently it has been observed

that a charge of electricity carried by any liquid bears a curious

relation to the atomic composition of that liquid. If the atom in

question is one of the sort that can combine with only a single other

atom (that is to say, a monovalent atom), each atom conveys a unit

charge, which is spoken of as an ion of electricity. But if a divalent

atom is in question the charge carried is double, and, similarly, a

trivalent atom carries a triple charge. As there are no intermediate

charges it is obvious that here a very close relation is suggested

between electrical units and the atomic units of matter.

This, however, is only a beginning. Far more interesting are the results

obtained by the study of gases in their relation to the conduction

of electricity. As is well known, gases under ordinary conditions are

nonconductors. But there are various ways in which a gas may be changed

so as to become a conductor; for example, by contact with incandescent

metals or with flame, or by treating with ultra-violet light, with

Rôntgen rays, or with the rays of a radio-active substance. Now the

all-important question is as to just what change has taken place in the

gas so treated to make it a conductor of electricity. I cannot go into

details here as to the studies that have been addressed to the answer

of this question, but I will briefly epitomize what, for our present

purpose, are the important results. First and foremost of these is the

fact that a gas thus rendered conductive contains particles that can

be filtered out of it by passing the gas through wool or through water.

These particles are the actual agents of conduction of electricity,

since the gas when filtered ceases to be conductive. But there is

another way in which the particles may be removed--namely, by action

of electricity itself. If the gas be caused to pass between two metal

plates, one of them insulated and attached to an electrometer, a charge

of positive electricity at high potential sent through the other plate

will drive part of the particles against the insulated plate. This

proves that the particles in question are positively electrified.

The amount of the charge which they carry may be measured by the

electrometer.

The aggregate amount of the electrical charge carried by these minute

particles in the gas being known, it is obvious that could we know the

number of particles involved the simplest calculation would determine

the charge of each particle. Professor Thompson devised a singularly

ingenious method of determining this number. The method was based on

the fact discovered by C. T. R. Wilson that charged particles acted as

nuclei round which small drops of water condense much as dust particles

serve the same purpose. "In dust-free air," says Professor Thompson,

"as Aitken showed, it is very difficult to get a fog when damp air is

cooled, since there are no nuclei for the drops to condense round. If

there are charged particles in dust-free air, however, the fog will be

deposited round these by super-saturation far less than that required to

produce any appreciable fog when no charged particles are present.

"Thus, in sufficiently supersaturated damp air a cloud is deposited on

these charged particles and they are thus rendered visible. This is the

first step towards counting them. The drops are, however, far too small

and too numerous to be counted directly. We can, however, get their

number indirectly as follows: suppose we have a number of these

particles in dust-free air in a closed vessel, the air being saturated

with water-vapor; suppose now that we produce a sudden expansion of the

air in the vessel; this will cool the air, it will be supersaturated

with vapor, and drops will be deposited round the charged particles. Now

if we know the amount of expansion produced we can calculate the cooling

of the gas, and, therefore, the amount of water deposited. Thus we know

the volume of water in the form of drops, so that if we know the volume

of one drop we can deduce the number of drops. To find the size of a

drop, we make use of the investigations made by Sir George Stokes on the

rate at which small spheres fall through the air. In consequence of

the viscosity of the air small bodies fall exceedingly slowly, and the

smaller they are the slower they fall." *

Professor Thompson gives us the formula by which Stokes made his

calculation. It is a relatively simple algebraic one, but need not be

repeated here. For us it suffices that with the aid of this formula,

by merely measuring the actual descent of the top of a vapor cloud,

Professor Thompson was able to find the volume of the drops and thence

the number of particles. The number of particles being known, the

charge of electricity carried by each could be determined, as already

suggested. Experiments were made with air, hydrogen, and carbonic acid,

and it was found that the particles had the same charge in all of these

gases. "A strong argument," says Professor Thompson, "in favor of

the atomic character of electricity." When we add that the charge in

question was found to be the same as the unit charge of an ion in a

liquid, it will be seen that the experiment has other points of interest

and suggestiveness.

Even more interesting in some regards were the results of computation

as to the actual masses of the charged particles in question. Professor

Thompson found that the carrier of a negative charge could have only

about one-thousandth part of the mass of a hydrogen atom, which latter

had been regarded as the smallest mass able to have an independent

existence. Professor Thompson gave the name corpuscle to these units

of negative electricity; they are now more generally termed electrons.

"These corpuscles," he says, "are the same however the electrification

may have risen or wherever they may be found. Negative electricity in a

gas at a low pressure has thus a structure analogous to that of a gas,

the corpuscles taking the place of the molecules. The 'negative electric

fluid,' to use the old notation, resembles the gaseous fluid with a

corpuscular instead of a molecular structure.'" Professor Thompson does

not hesitate to declare that we now "know more about 'electric fluid'

than we know about such fluids as air or water."*3* The results of his

studies lead him, he declares, "to a view of electrification which

has a striking resemblance to that of Franklin's _One Fluid Theory of

Electricity_. Instead of taking, as Franklin did, the electric fluid

to be positive electricity," he says, "we take it to be negative. The

'electric fluid' of Franklin corresponds to an assemblage of corpuscles,

negative electrification being a collection of these corpuscles. The

transference of electrification from one place to another is effected

by the motion of corpuscles from the place where there is a gain of

positive electrification to the place where there is a gain of

negative. A positively electrified body is one that has lost some of its

corpuscles."*4* According to this view, then, electricity is not a form

of energy but a form of matter; or, to be more precise, the electrical

corpuscle is the fundamental structure out of which the atom of matter

is built. This is a quite different view from that scarcely less recent

one which regards electricity as the manifestation of ether strain,

but it must be admitted that the corpuscular theory is supported by a

marvellous array of experimental evidence, though it can perhaps hardly

be claimed that this brings the theory to the plane of demonstration.

But all roads of physical science of late years have seemed to lead

towards the electron, as will be made further manifest when we consider

the phenomena of radio-activity, to which we now turn.

RADIO-ACTIVITY

In 1896, something like a year after the discovery of the X-ray,

Niewenglowski reported to the French Academy of Sciences that the

well-known chemical compound calcium sulphide, when exposed to sunlight,

gave off rays that penetrated black paper. He had made his examinations

of this substance, since, like several others, it was known to exhibit

strong fluorescent or phosphorescent effects when exposed to the cathode

rays, which are known to be closely connected with the X-rays. This

discovery was followed very shortly by confirmatory experiments made by

Becquerel, Troost, and Arnold, and these were followed in turn by the

discovery of Le Bon, made almost simultaneously, that certain bodies

when acted upon by sunlight give out radiations which act upon a

photographic plate. These manifestations, however, are not the effect of

radio-activity, but are probably the effects of short ultra-violet

light waves, and are not produced spontaneously by the substances. The

radiations, or emanations, of the radio-active substances, on the other

hand, are given out spontaneously, pass through substances opaque to

ordinary light, such as metal plates, act upon photographic plates, and

discharge electrified bodies. The substances uranium, thorium, polonium,

radium, and their compounds are radioactive, radium being by far the

most active.

The first definite discovery of such a radio-active substance was made

by M. Henri Becquerel, in 1896, while making some experiments upon

the peculiar ore pitch-blende. Pitch-blende is a heavy, black,

pitchy-looking mineral, found principally at present in some parts of

Saxony and Bohemia on the Continent, in Cornwall in Great Britain, and

in Colorado in America. It is by no means a recently discovered mineral,

having been for some years the source of uranium and its compounds,

which, on account of their brilliant colors, have been used in

dye-stuffs and some kinds of stained glass. It is a complex mineral,

containing at least eight or ten elements, which can be separated from

it only with great difficulty and by complicated chemical processes.

Becquerers discovery was brought about by a lucky accident, although,

like so many other apparently accidental scientific discoveries, it was

the outcome of a long series of scientific experiments all trending in

the same direction. He had found that uranium, when exposed to the sun's

rays, appeared to possess the property of absorbing them and of then

acting upon a photographic plate. Since pitch-blende contained uranium,

or uranium salts, he surmised that a somewhat similar result might be

obtained with the ore itself. He therefore prepared a photographic plate

wrapped in black paper, intending to attempt making an impression on the

plate of some metal body interposed between it and the pitch-blende. For

this purpose he had selected a key; but as the day proved to be cloudy

he put the plate, with the key and pitch-blende resting upon it, in

a dark drawer in his desk, and did not return to the experiment for

several days. Upon doing so, however, he developed the plate without

further exposure, when to his astonishment he found that the developed

negative showed a distinct impression of the key. Clearly this was the

manifestation of a property heretofore unknown in any natural substance,

and was strikingly similar to the action of the Roentgen rays. Further

investigations by Lord Kelvin, Beattie, Smolan, and Rutherford confirmed

the fact that, like the Roentgen rays, the uranium rays not only acted

upon the photographic plate but discharged electrified bodies. And what

seemed the more wonderful was the fact that these "Becquerel rays," as

they were now called, emanated spontaneously from the pitch-blende.

But although this action is analogous to the Roentgen rays, at least as

regards its action upon the photographic plate and its influence on

the electric field, its action is extremely feeble in comparison, the

Roentgen rays producing effects in minutes, or even seconds, which

require days of exposure to uranium rays. The discovery of the

radio-active properties of uranium was followed about two years later by

the discovery that thorium, and the minerals containing thorium,

possess properties similar to those of uranium. This discovery was

made independently and at about the same time by Schmidt and Madame

Skaldowska Curie. But the importance of this discovery was soon

completely overshadowed by the discovery of radium by Madame Curie,

working with her husband, Professor Pierre Curie, at the École

Polytechnique in Paris. Madame Curie, stimulated by her own discoveries

and those of the other scientists just referred to, began a series of

examinations upon various substances by numerous complicated methods

to try and find a possible new element, as certain peculiarities of the

substances found in the pitch-blende seemed to indicate the presence of

some hitherto unknown body. The search proved a most difficult one

on account of the peculiar nature of the object in question, but the

tireless enthusiasm of Madame Curie knew nothing of insurmountable

obstacles, and soon drew her husband into the search with her. Her first

discovery was that of the substance polonium--so named by Madame Curie

after her native country, Poland. This proved to be another of the

radio-active substances, differing from any other yet discovered, but

still not the sought-for element. In a short time, however, the two

Curies made the great discovery of the element radium--a substance

which, according to their estimate, is some one million eight hundred

thousand times more radioactive than uranium. The name for this element,

_radium_, was proposed by Madame Curie, who had also suggested the term

"radio-activity."

The bearing of the discovery of radium and radioactivity upon theories

of the atom and matter will be considered in a moment; first the more

tangible qualities of this wonderful substance may be briefly referred

to. The fact that radio-active emanations traverse all forms of matter

to greater or less depth--that is, pass through wood and iron with

something the same ease that light passes through a window-glass--makes

the subject one of greatest interest; and particularly so as the

demonstration of this fact is so tangible. While the rays given out by

radium cannot, of course, be seen by the unaided eye, the effects of

these rays upon certain substances, which they cause to phosphoresce,

are strikingly shown. One of such substances is the diamond, and a

most striking illustration of the power of radium in penetrating opaque

substances has been made by Mr. George F. Kunz, of the American Museum

of Natural History. Mr. Kunz describes this experiment as follows:

"Radium bromide of three hundred thousand activity was placed in a

sealed glass tube inside a rubber thermometer-holder, which was tightly

screwed to prevent any emanation of any kind from passing through the

joints. This was placed under a heavy silver tureen fully one-sixteenth

of an inch in thickness; upon this were placed four copper plates, such

as are used for engraving; upon these a heavy graduated measuring-glass

10 cm. in diameter; this was filled with water to a depth of six inches.

A diamond was suspended in the water and immediately phosphoresced.

Whenever the tube of radium was drawn away more than two or three feet

the phosphoresce ceased; whenever it was placed under the tureen the

diamond immediately phosphoresced again. This experiment proves that the

active power of the radium penetrated the following substances:

"Glass in the form of a tube, sealed at both ends; the rubber

thermometer-holder; silver tureen; four copper plates; a glass vase or

measuring-glass one-quarter of an inch in thickness; three inches of

water. There is no previously known substance or agent, whether it be

even light or electricity, that possesses such wonderfully penetrative

powers."*5*

THE NATURE OF EMANATIONS FROM RADIO-ACTIVE BODIES

What, then, is the nature of these radiations? Are they actually

material particles hurled through the ether? Or are they like light--and

possibly the Roentgen rays--simply undulations in the ether? As yet this

question is an open one, although several of the leading investigators

have postulated tentative hypotheses which at least serve as a working

basis until they are either confirmed or supplanted. On one point,

however, there seems to be unanimity of opinion--there seems to be

little question that there are at least three different kinds of rays

produced by radio-active substances. According to Sir William Crookes,

the first of these are free electrons, or matter in an ultra-gaseous

state, as shown in the cathode stream. These particles are extremely

minute. They carry a negative charge of electricity, and are identified

with the electric corpuscles of Thompson. Rays of the second kind are

comparable in size to the hydrogen atom, and are positively electrified.

These are easily checked by material obstructions, although they render

the air a conductor and affect photographic plates. The third are very

penetrating rays, which are not deflected by electricity and which are

seemingly identical with Roentgen rays. Professor E. Rutherford has

named these rays beta (B), alpha (a), and gamma (v) rays respectively.

Of these the beta rays are deviated strongly by the magnetic field, the

alpha much less so--very slightly, in fact--while the gamma rays are not

affected at all. The action of these three different sets of rays upon

certain substances is not the same, the beta and gamma rays acting

strongly upon barium platinocyanide, but feebly on Sidot's blende,

while the alpha rays act exactly the reverse of this, acting strongly on

Sidot's blende.

If a surface is coated with Sidot's blende and held near a piece of

radium nitrate, the coated surface begins to glow. If now it is examined

with a lens, brilliant sparks or points can be seen. As the radium is

brought closer and closer these sparks increase in number, until, as Sir

William Crookes says, we seem to be witnessing a bombardment of flying

atoms hurled from the radium against the surface of the blende. A little

instrument called a spinthariscope, devised by Dr. Crookes and on sale

at the instrument and optical-goods shops, may be had for a trifling

sum. It is fitted with a lens focused upon a bit of Sidot's blende and

radium nitrate, and in a dark room shows these beautiful scintillations

"like a shower of stars." A still less expensive but similar device

is now made in the form of a microscopic slide, to be used with the

ordinary lens.

As we said a moment ago, radium appears to be an elementary substance,

as shown by its spark-spectrum being different from that of any other

known substance--the determinative test as fixed by the International

Chemical Congress. A particle of radium free from impurities should,

therefore, according to the conventional conception of an element,

remain unchanged and unchangeable. If any such change did actually take

place it would mean that the conception of the Daltonian atom as

the ultimate particle of matter is definitively challenged from a new

direction. This is precisely what has taken place. In July of 1903 Sir

William Ramsay and Mr. Soddy, in making some experiments with radium,

saw produced, apparently from radium emanations, another quite different

and distinct substance, the element helium. The report of such a

revolutionary phenomenon was naturally made with scientific caution.

Though the observation seemed to prove the actual transformation of one

element into another, Professor Ramsay himself was by no means ready to

declare the absolute certainty of this. Yet the presumption in favor

of this interpretation of the observed phenomena is very strong; and so

cautious a reasoner as Professor Rutherford has declared recently that

"there can be no doubt that helium is derived from the emanations of

radium in consequence of changes of some kind occurring in it."*6*

"In order to explain the presence of helium in radium on ordinary

chemical lines," says Professor Rutherford, "it has been suggested that

radium is not a true element, but a molecular compound of helium with

some substance known or unknown. The helium compound gradually breaks

down, giving rise to the helium observed. It is at once obvious that

this postulated helium compound is of an entirely different character to

any other compound previously observed in chemistry. Weight for weight,

it emits during its change an amount of energy at least one million

times greater than any molecular compound known. In addition, it must

be supposed that the rate of breaking up of the helium compound is

independent of great ranges of temperature--a result never before

observed in any molecular change. The helium compound in its breaking

up must give rise to the peculiar radiations and also pass through the

successive radio-active change observed in radium.... On the other

hand, radium, as far as it has been examined, has fulfilled every

test required of an element. It has a well-marked and characteristic

spectrum, and there is no reason to suppose that it is not an element in

the ordinarily accepted sense of the term."*7*

THE SOURCE OF ENERGY OF RADIO-ACTIVITY

In 1903 Messrs. Curie and Laborde*8* made the remarkable announcement

that a crystal of radium is persistently warmer than its surrounding

medium; in other words, that it is perpetually giving out heat without

apparently becoming cooler. At first blush this seemed to contradict the

great physical law of the conservation of energy, but physicists were

soon agreed that a less revolutionary explanation of the phenomenon is

perfectly tenable. The giving off of heat is indeed only an additional

evidence of the dissipation of energy to which the radio-active atom

is subjected. And no one now believes that radio-activity can persist

indefinitely without actually exhausting the substance of the atom. Even

so, the evidence of so great a capacity to give out energy is startling,

and has given rise to various theories (all as yet tentative) in

explanation. Thus J. Perrin*9* has suggested that atoms may consist of

parts not unlike a miniature planetary system, and in the atoms of the

radio-elements the parts more distant from the centre are continually

escaping from the central attraction, thus giving rise to the

radiations. Monsieur and Madame Curie have suggested that the energy may

be borrowed from the surrounding air in some way, the energy lost by

the atom being instantly regained. Pilipo Re,*10* in 1903, advanced the

theory that the various parts of the atom might at first have been free

particles constituting an extremely tenuous nebula.

These parts gradually becoming collected around condensed centres have

formed what we know as the atoms of elements, the atom thus becoming

like an extinct sun of the solar system. From this point of view the

radio-active atoms represent an intermediate stage between nebulae

and chemical atoms, the process of contraction giving rise to the heat

emissions.

Lord Kelvin has called attention to the fact that when two pieces of

paper, one white and the other black, are placed in exactly similar

glass vessels of water and exposed to light, the temperature of the

vessel containing the black paper is raised slightly higher than the

other. This suggests the idea that in a similar manner radium may keep

its temperature higher than the surrounding air by the absorption of

other radiations as yet unknown.

Professor J. J. Thompson believes that the source of energy is in the

atom itself and not external to it. "The reason," he says, "which

induces me to think that the source of the energy is in the atom of

radium itself and not external to it is that the radio-activity of

substances is in all cases in which we have been able to localize it a

transient property. No substance goes on being radio-active very long.

It may be asked, how can this statement be reconciled with the fact

that thorium and radium keep up their activity without any appreciable

falling off with time. The answer to this is that, as Rutherford and

Soddy have shown in the case of thorium, it is only an exceedingly small

fraction of the mass which is at any one time radio-active, and that

this radio-active portion loses its activity in a few hours, and has to

be replaced by a fresh supply from the non-radio-active thorium."*11*

If Professor Thompson's view be correct, the amount of potential energy

inherent in the atom must be enormous.

RADIO-ACTIVITY AND THE STRUCTURE OF THE ATOM

But whatever the source of the energy displayed by the radio-active

substances, it is pretty generally agreed that the radio-activity of

the radio-elements results in the disruption of their atoms. Since all

substances appear to be radio-active in a greater or less degree,

it would seem that, unless there be a very general distribution

of radio-active atoms throughout all substances, all atoms must be

undergoing disruption. Since the distribution of radio-active matter

throughout the earth is so great, however, it is as yet impossible to

determine whether this may not account for the radio-activity of all

substances.

As we have just seen, recent evidence seems to point to the cause of the

disruption of radio-active atoms as lying in the atoms themselves. This

view is quite in accord with modern ideas of the instability of certain

atoms. It has been suggested that some atoms may undergo a slower

disintegration without necessarily throwing off part of their systems

with great velocity. It is even possible that all matter may be

undergoing transformation, this transformation tending to simplify

and render more stable the constituents of the earth. The radio-active

bodies, however, are the only ones that have afforded an opportunity for

studying this transformation. In these the rapidity of the change would

be directly proportionate to their radioactivity. Radium, according

to the recent estimate of the Curies, would be disintegrating over

a million times more rapidly than uranium. Since the amount of

transformation occurring in radium in a year amounts to from 1-2000

to 1-10,000 of the total amount, the time required for the complete

transformation of an atom of uranium would be somewhere between two

billion and ten billion years--figures quite beyond the range of human

comprehension.

Various hypotheses have been postulated to account for the instability

of the atom. Perhaps the most thinkable of these to persons not

specially trained in dealing with abstruse subjects is that of Professor

Thompson. It has the additional merit, also, of coming from one of the

best-known investigators in this particular field. According to this

hypothesis the atom may be considered as a mass of positively and

negatively charged particles, all in rapid motion, their mutual forces

holding them in equilibrium. In case of a very complex structure of

this kind it is possible to conceive of certain particles acquiring

sufficient kinetic energy to be projected from the system. Or the

constraining forces may be neutralized momentarily, so that the particle

is thrown off at the same velocity that it had acquired at the instant

it is released. The primary cause of this disintegration of the atom

may be due to electro-magnetic radiation causing loss of energy of the

atomic system.

Sir Oliver Lodge suggests that this instability of the atom may be the

result of the atom's radiation of energy. "Lodge considered the simple

case of a negatively charged electron revolving round an atom of

mass relatively large but having an equal positive charge and held in

equilibrium by electrical forces. This system will radiate energy, and

since the radiation of energy is equivalent to motion in a resisting

medium, the particle tends to move towards the centre and its speed

consequently increases. The rate of radiation of energy will increase

rapidly with the speed of the electron. When the speed of the electron

becomes very nearly equal to the velocity of light, according to Lodge,

the system is unstable. It has been shown that the apparent mass of an

electron increases very rapidly as the speed of light is approached, and

is theoretically infinite at the speed of light. There will be at this

stage a sudden increase of the mass of the revolving atom, and, on the

supposition that this stage can be reached, a consequent disturbance of

the balance of forces holding the system together. Lodge considers it

probable that under these conditions the parts of the system will break

asunder and escape from the sphere of one another's influence.

"It is probable," adds Rutherford, "that the primary cause of the

disintegration of the atom must be looked for in the 1 ss of energy of

the atomic system due to electro-magnetic radiation."*12*

Several methods have been devised for testing the amount of heat given

off by radium and its compounds, and for determining its actual rise

in temperature above that of the surrounding atmosphere. One of these

methods is to place some substance, such as barium chloride, in a

calorimeter, noting at what point the mercury remains stationary. Radium

is then introduced, whereupon the mercury in the tube gradually rises,

falling again when the radium is removed. By careful tests it has

been determined that a gram of radium emits about twenty-four hundred

gram-calories in twenty-four hours. On this basis a gram of radium in a

year emits enough energy to dissociate about two hundred and twenty-five

grams of water.

What seems most remarkable about this constant emission of heat by the

radium atom is that it does not apparently draw upon external sources

for it, but maintains it by the internal energy of the atom itself. This

latent energy must be enormous, but is only manifested when the atom

is breaking up. In this process of disruption many of the particles are

thrown off; but the greater part seem to be stopped in their flight in

the radium itself, so that their energy of motion is manifested in the

form of heat. Thus, if this explanation is correct, the temperature of

the radium is maintained above that of surrounding substances by the

bombardment of its own particles. Since the earth and the atmosphere

contain appreciable quantities of radio-active matter, this must play

a very important part in determining the temperature of the globe--so

important a part, indeed, that all former estimates as to the probable

length of time during which the earth and sun will continue to radiate

heat are invalidated. Such estimates, for example, as that of Lord

Kelvin as to the probable heat-giving life of the sun must now be

multiplied from fifty to five hundred times.

In like manner the length of time that the earth has been sufficiently

cool to support animal and vegetable life must be re-estimated. Until

the discovery of radium it seemed definitely determined that the earth

was gradually cooling, and would continue to cool, un til, like the

moon, it would become too cold to support any kind of vegetable or

animal life whatever. But recent estimates of the amount of radio-active

matter in the earth and atmosphere, and the amount of heat constantly

given off from this source, seem to indicate that the loss of heat

is (for the moment) about evenly balanced by the heat given out by

radio-active matter. Thus at the beginning of the new century we see

the phenomenon of a single discovery in science completely overturning

certain carefully worked out calculations, although not changing the

great principles involved. It is but the repetition of the revolutionary

changes that occur at intervals in the history of science, a simple

discovery setting at naught some of the most careful calculations of a

generation.

V. THE MARINE BIOLOGICAL LABORATORY AT NAPLES

THE AQUARIUM

MANY tourists who have gone to Naples within recent years will recall

their visit to the aquarium there among their most pleasant experiences.

It is, indeed, a place worth seeing. Any Neapolitan will direct you to

the beautiful white building which it occupies in the public park close

by the water's side. The park itself, statue-guarded and palm-studded,

is one of the show-places of the city; and the aquarium building,

standing isolated near its centre, is worthy of its surroundings. As

seen from the bay, it gleams white amid the half-tropical foliage,

with the circling rampart of hills, flanked by Vesuvius itself, for

background. And near at hand the picturesque cactus growth scrambling

over the walls gives precisely the necessary finish to the otherwise

rather severe type of the architecture. The ensemble prepares one to be

pleased with whatever the structure may have to show within.

It prepares one also, though in quite another way, for a surprise; for

when one has crossed the threshold and narrow vestibule, while the gleam

of the outside brightness still glows before his eyes, he is plunged

suddenly into what seems at first glimpse a cavern of Egyptian darkness,

and the contrast is nothing less than startling. To add to the effect,

one sees all about him, near the walls of the cavern, weird forms of

moving creatures, which seem to be floating about lazily in the air, in

grottos which glow with a dim light or sparkle with varied colors. One

is really looking through glass walls into tanks of water filled with

marine life; but both glass and water are so transparent that it is

difficult at first glimpse to realize their presence, unless a stream of

water, with its attendant bubbles, is playing into the tanks. And even

then the effect is most elusive; for the surface of the water, which

you are looking up to from below, mirrors the contents of the tanks so

perfectly that it is difficult to tell where the reality ends and the

image begins, were it not that the duplicated creatures move about with

their backs downward in a scene all topsy-turvy. The effect is most

fantastic.

More than that, it is most beautiful as well. You are, in effect, at the

bottom of the ocean--or rather, at the bottom of many oceans in one. No

light comes to you except through the grottos about you--grottos haunted

by weird forms of the deep, from graceful to grotesque, from almost

colorless to gaudy-hued. To your dilated pupils the light itself has

the weird glow of unreality. It is all like the wonders of the Arabian

Nights made tangible or like a strange spectacular dream. If one were in

a great diving-bell at the bottom of the veritable ocean he could hardly

feel more detached from the ordinary aerial world of fact.

As one recovers his senses and begins to take definite note of things

about him he sees that each one of the many grottos has a different set

of occupants, and that not all of the creatures there are as unfamiliar

as at first they seemed. Many of the fishes, for example, and the

lobsters, crabs, and the like, are familiar enough under other

conditions, but even these old acquaintances look strange under these

changed circumstances. But for the rest there are multitudes of forms

that one had never seen or imagined, for the sea hides a myriad of

wonders which we who sail over its surface, and at most glance dimly

a few feet into its depths, hardly dream of. Even though one has seen

these strange creatures "preserved" in museums, he does not know

them, for the alleged preservation there has retained little enough of

essential faciès of the real creature, which the dead shell can no more

than vaguely suggest.

Here, however, we see the real thing. Each creature lives and moves in a

habitat as nearly as may be like that which it haunted when at

liberty, save that tribes that live at enmity with one another are here

separated, so that the active struggle for existence, which plays

so large a part in the wild life of sea as well as land, is not

represented. For the rest the creatures of the deep are at home in these

artificial grottos, and disport themselves as if they desired no other

residence. For the most part they pay no heed whatever to the human

inspectors without their homelike prisons, so one may watch their

activities under the most favorable conditions.

It is odd to notice how curiously sinuous are all the movements, not

alone of the fish, but of a large proportion of the other forms of

moving life of the waters. The curve, the line of beauty, is the symbol

of their every act; there are no angles in their world. They glide

hither and yon, seemingly without an effort, and always with wavy,

oscillating gracefulness. The acme of this sinuosity of movement is

reached with those long-drawn-out fishes the eels. Of these there are

two gigantic species represented here--the conger, a dark-skinned,

rather ill-favored fellow, and the beautiful Italian eel, with a

velvety, leopard-spotted skin. These creatures are gracefulness itself.

They are ribbon-like in tenuousness, and to casual glance they give the

impression of long, narrow pennants softly waving in a gentle breeze.

The great conger--five or six feet in length--has, indeed, a certain

propensity to extend himself rigidly in a fishlike line and lie

immovable, but the other species is always true to his colors, so to

say--his form is always outlined in curves.

The eels attract their full share of attention from the visitors, but

there is one family of creatures which easily holds the palm over all

the others in this regard. These are the various representatives of the

great cult of squids and cuttle-fishes. The cuttle-fish proper--who,

of course, is no fish at all--is shaped strangely like a diminutive

elephant, with a filmy, waving membrane along its sides in lieu of legs.

Like the other members of his clan, he can change his color variously.

Sometimes he is of a dull brown, again prettily mottled; then, with

almost kaleidoscopic suddenness, he will assume a garb beautifully

striped in black and white, rivalled by nothing but the coat of the

zebra. The cuttle-fish is a sluggish creature, seeking out the darker

corners of his grotto, and often lying motionless for long periods

together. But not so the little squid. He does not thrive in captivity,

and incessantly wings his way back and forth, with slow, wavy

flappings of his filmy appendages, until he wears himself out and dies

unreconciled.

In marked contrast with both cuttle-fish and squid is their cousin the

octopus--a creepy, crawly creature, like eight serpents in one--at once

the oddest and the most fascinating creature in the entire aquarium. You

will find a crowd almost always before his grotto watching his curious

antics. Usually slow and deliberate in movement, he yet has capacity

for a certain agility. Now and again he dives off suddenly, head first,

through the water, with the directness if not quite with the speed of an

arrow. A moment later, tired of his flight, he sprawls his eight webbed

legs out in every direction, breaking them seemingly into a thousand

joints, and settles back like an animated parachute awreck. Then

perchance he perches on a rock knowingly, with the appearance of

owl-like wisdom, albeit his head looks surprisingly like a frog's. Anon

he holds his head erect and stretches out his long arms in what is most

palpably a yawn. Then, for pure diversion, he may hold himself

half erect on his umbrella frame of legs and sidle along a sort of

quadrille--a veritable "eight hands in round."

But all the while he conveys distinctly the impression of a creature to

the last degree blasé. Even when a crab is let down into his grotto by

an attendant for the edification of the visitors the octopus seems to

regard it with only lukewarm interest. If he deigns to go in pursuit,

it is with the air of one who says, "Anything to oblige," rather than

of eagerness for a morsel of food. Yet withal, even though unhurried,

he usually falls upon the victim with surprising sureness of aim,

encompassing it in his multiform net. Or perhaps, thinking the game

hardly worth so much effort, he merely reaches out suddenly with one

of his eight arms--each of which is a long-drawn-out hand as well--and

grasps the victim and conveys it to his distensible maw without so much

as changing his attitude.

All this of the giant octopus--brown and warty and wrinkled and blasé.

But the diminutive cousin in the grotto with the jellyfishes is a bird

of quite another feather. Physically he is constructed on the same model

as the other, but his mentality is utterly opposed. No grand rôles for

him; his part is comedy. He finds life full of interest. He is satisfied

with himself and with the world. He assumes an aspect of positive

rakishness, and intelligence, so to say, beams from his every limb. All

day long he must be up and doing. For want of better business he will

pursue a shrimp for hours at a time with the zest of a true sportsman.

Now he darts after his intended prey like a fox-hound. Again he resorts

to finesse, and sidles off, with eyes fixed in another direction, like

a master of stratagem. To be sure, he never catches the shrimp--but what

of that? The true sportsman is far removed from the necessity for mere

material profit. I half suspect that little octopus would release the

shrimp if once he caught him, as the true fisherman throws back the

excess of his catch. It is sport, not game, that he covets.

THE LABORATORY AND ITS FOUNDER

When one has made the circuit of the aquarium he will have seen and

marvelled at some hundreds of curious creatures utterly unlike anything

to be found above water. Brightly colored starfishes, beautiful

sea-urchins, strange stationary ascidians, and flower-like sea-anemones,

quaint sea-horses, and filmy, fragile jellyfishes and their multiform

kin--all seem novel and wonderful as one sees them in their native

element. Things that appear to be parts of the rocky or sandy bed of the

grottos startle one by moving about, and thus discovering themselves

as living creatures, simulating their environment for purposes of

protection. Or perhaps what seems to be a giant snail suddenly unfurls

wings from its seeming shell, and goes waving through the water, to the

utter bewilderment of the beholder. Such freaks as this are quite

the rule among the strange tribes of the deep, for the crowding of

population there makes the struggle for existence keen, and necessitates

all manner of subterfuges for the preservation of species.

Each and every one of the thirty-odd grottos will repay long

observation, even on the part of the most casual visitor, and when one

has seen them all, he will know more at first hand of the method of life

of the creatures of the sea than all the books could teach him. He will

depart fully satisfied, and probably, if he be the usual sight-seer,

he will never suspect that what he has seen is really but an incidental

part of the institution whose building he has entered. Even though he

note casually the inscription "Stazione Zoôlogica" above the entrance,

he may never suspect that the aquarium he has just visited is only an

adjunct--the popular exhibit, so to speak--of the famous institution

of technical science known to the English-speaking world as the Marine

Biological Laboratory at Naples. Yet such is the fact. The aquarium

seems worthy enough to exist by and for itself. It is a great popular

educator as well as amuser, yet its importance is utterly insignificant

compared with the technical features of the institution of which it is

an adjunct.

This technical department, the biological laboratory proper, has its

local habitation in the parts of the building not occupied by the

aquarium--parts of which the general public, as a rule, sees nothing.

There is, indeed, little to see that would greatly interest the casual

inspector, for in its outward aspects one laboratory is much like

another, a seeming hodgepodge of water-tanks, glass jars of specimens,

and tables for microscopes. The real status of a laboratory is not

determined by the equipment.

And yet it will not do to press this assertion too far, for in one sense

it is the equipment of the Naples laboratory that has made it what it

is. Not, however, the equipment in the sense of microscopes and other

working paraphernalia. These, of course, are the best of their kind, but

machinery alone does not make a great institution, any more than

clothes make the man. The all-essential and distinctive equipment of

the laboratory reveals itself in its personnel. In the present case, as

always in a truly great institution of any kind, there is one dominating

personality, one moving spirit. This is Dr. Anton Dohrn, founder of the

laboratory, and still its controller and director, in name and in fact.

More than twenty-five years ago Dr. Dohrn, then a young man fresh from

the universities of his native Germany, discovered what he felt to be

a real need in the biological world. He was struck with the fact that

nowhere in the world could be found an establishment affording good

opportunities for the study of marine life. Water covers three-fifths of

the earth's surface, as everybody knows, and everywhere this water teems

with life, so that a vast preponderance of the living things of the

globe find their habitat there. Yet the student who might desire to make

special studies of this life would find himself balked at the threshold

for want of opportunity.

It was no great thing to discover this paucity, which, indeed, fairly

beckoned the discoverer. The great thing was to supply the deficiency,

and this was what Dr. Dohrn determined to do. He selected Naples as the

best location for the laboratory he proposed to found, because of its

climate and its location beside the teeming waters of the Mediterranean.

He organized a laboratory; he called about him a corps of able

assistants; he made the Marine Biological Laboratory at Naples famous,

the Mecca of all biological eyes throughout the world. It was not all

done in a day. It was far enough from being done without opposition and

discouragement; but these are matters of history which Dr. Dohrn now

prefers not to dwell upon. Suffice it that the result aimed at was

finally achieved, and in far greater measure than could at first be

hoped for.

And from that day till this Naples has been the centre of that branch

of biological inquiry which has for its object the investigation of

problems best studied with material gathered from the sea. And this,

let me hasten to add, includes far more than a mere study of the life

histories of marine animals and plants as such. It includes problems of

cell activity, problems of heredity, life problems of many kinds, having

far wider horizons than the mere question as to how a certain fish or

crustacean lives and moves and has its being.

Dr. Dohrn's chief technical associates are all Germans, like their

leader, but, like him also, all gifted with a polyglot mastery of

tongues that has stood them in good stead in their intercourse with the

biologists of many nationalities who came to work at the laboratory. I

must not pause to dwell upon the personnel of the staff in general,

but there is one other member who cannot be overlooked even in the most

casual survey of the work of the institution. One might almost as well

forget Dr. Dohrn himself as to overlook Signor Lo Bianco, chief of the

collecting department. Signor Bianco it is who, having expert knowledge

of the haunts and habits of every manner of marine creature, can direct

his fishermen where to find and how to secure whatever rare specimen any

worker at the laboratory may desire. He it is, too, who, by studying old

methods and inventing new ones, has learned how to preserve the delicate

forms for subsequent study in lifelike ensemble that no one else can

quite equal. Signor Bianco it is, in short, who is the indispensable

right-hand man of the institution in all that pertains to its practical

working outside the range of the microscope. Each night Signor Lo Bianco

directs his band of fishermen as to what particular specimens are most

to be sought after next day to meet the needs of the workers in the

laboratory. Before sunrise each day, weather permitting, the little

scattered fleet of boats is far out on the Bay of Naples; for the

surface collecting, which furnishes a large share of the best material,

can be done only at dawn, as the greater part of the creatures thus

secured sink into the retirement of the depths during the day, coming

to the surface to feed only at night. You are not likely to see the

collecting party start out, therefore, but if you choose you may see

them return about nine or ten o'clock by going to the dock not far

from the laboratory. The boats come in singly at about this hour, their

occupants standing up to row, and pushing forward with the oars, after

the awkward Neapolitan fashion. Many of the fishermen are quaint

enough in appearance; some of them have grown old in the service of the

laboratory. The morning's catch is contained in glass jars placed

in baskets especially constructed for the purpose. The baskets have

handles, but these are quite superfluous except to lift them from the

boats, for in the transit to the laboratory the baskets are carried,

as almost everything else is carried in Naples, on the head. To the

novitiate it seems a striking risk to pile baskets of fragile glass and

even more fragile specimens one above another, and attempt to balance

the whole on the head, but nothing could be easier, or seemingly more

secure, for these experts. Arrived at the laboratory, the jars are

turned over to Signer Lo Bianco and his assistants, who sort the

material, and send to each investigator in the workrooms whatever he may

have asked for.

Of course surface-skimming is not the only method of securing material

for the laboratory. The institution owns a steam-launch named the

_Johannes Müller_, in honor of the great physiologist, which operates

a powerful dredge for securing all manner of specimens from the

sea-bottom. Then ordinary lines and nets are more or less in requisition

for capturing fish. And in addition to the regular corps of collectors,

every fisherman of the neighborhood has long since learned to bring

to the laboratory all rare specimens of any kind that he may chance to

capture. So in one way and another the institution makes sure of having

in tribute all that the richly peopled waters of the Mediterranean can

offer. And this well-regulated system of collecting, combined with the

richness of the fauna and flora of the Bay of Naples, has no small share

in the success of the marine laboratory. But these, of course, were

factors that Dr. Dohrn took into account from the beginning.

Indeed, it was precisely with an eye to these important factors that

Naples was selected as the site of the future laboratory in the days

when the project was forming.

The Bay of Naples is most happily located for the needs of the

zoologist. It is not too far south to exclude the fauna of the temperate

zone, yet far enough south to furnish a habitat for many forms of

life almost tropical in character. It has, in short, a most varied and

abundant fauna. And, on the other hand, the large colony of Neapolitan

fishermen made it certain that skilled collectors would always be at

hand to make available the wealth of material. It requires no technical

education to appreciate the value of this to the original investigator,

particularly to the student of life problems. A skilful worker may do

much with a single specimen, as, for example, Johannes Mûller did half a

century ago with the one available specimen of amphioxus, the lowest of

vertebrates, then recently discovered. What Mûller learned from that one

specimen seems almost miraculous. But what if he had had a bucketful of

the little boneless creatures at his disposal, as the worker at Naples

now may have any day for the asking?

When it comes to problems of development, of heredity, a profusion

of material is almost a necessity. But here the creatures of the sea

respond to the call with amazing proficiency. Most of them are, of

course, oviparous, and it is quite the rule for them to deposit their

eggs by hundreds of thousands, by millions even. Everybody knows, since

Darwin taught us, that the average number of offspring of any given

species of animal or plant bears an inverse proportion to the liability

of that species to juvenile fatalities. When, therefore, we find a fish

or a lobster or other pelagic creature depositing innumerable eggs, we

may feel perfectly sure that the vast majority of the eggs themselves,

or the callow creatures that come out of them, will furnish food for

their neighbors at an early day. It is an unkind world into which

the resident of the deep is born. But his adversity is his human

contemporary's gain, and the biologist will hardly be blamed, even by

the most tender-hearted anti-vivisectionist, for availing himself freely

of material which otherwise would probably serve no better purpose than

to appease the appetite of some rapacious fish.

Their abundance is not the only merit, however, of the eggs of pelagic

creatures, in the eyes of the biologist. By equal good-fortune it

chances that colorless things are at a premium in the sea, since to

escape the eye of your enemy is a prime consideration. So the eggs in

question are usually transparent, and thus, shielded from the vision

of marine enemies, are beautifully adapted for the observation of the

biologist. As a final merit, they are mostly of convenient size for

manipulation under the microscope. For many reasons, then, the marine

egg offers incomparable advantages to the student of cell life, an egg

being the typical cell. And since nowadays the cell is the very focus of

attention in the biological world, the importance of marine laboratories

has been enhanced proportionately.

But of course not all the work can be done with eggs or with living

specimens of any kind. It is equally important on occasion to examine

the tissues of adult specimens, and for this, as a rule, the tissues

must first be subjected to some preserving and hardening process

preliminary to the cutting of sections for microscopical examination.

This is done simply enough in the case of some organisms, but there is

a large class of filmy, tenuous, fragile creatures in the sea population

of which the jellyfish may be mentioned as familiar examples. Such

creatures, when treated in an ordinary way, by dropping them into

alcohol, shrivel up, coming to resemble nothing in particular, and

ceasing to have any value for the study of normal structures. How to

overcome this difficulty was one of the problems attacked from the

beginning at the Naples laboratory. The chief part of the practical work

of these experiments fell to the share of Signor Lo Bianco. The success

that attended his efforts is remarkable. To-day you may see at the

laboratory all manner of filmy, diaphanous creatures preserved in

alcohol, retaining every jot of their natural contour, and thus offering

unexampled opportunities for study _en masse_, or for being sectioned

for the microscope. The methods by which this surprising result has been

accomplished are naturally different for different creatures; Signor Lo

Bianco has written a book telling how it all has been done. Perhaps the

most important principle involved with a majority of the more tenuous

forms is to stupefy the animal by gradually adding small quantities of

a drug, such as chloral, to the water in which the creature is detained.

When by this means the animal has been rendered so insensible that

it responds very sluggishly to stimuli, it is plunged into a toxic

solution, usually formaline, which kills it so suddenly that its muscles

in their benumbed state have not time to contract.

Any one who has ever tried to preserve a jellyfish, for example, by

ordinary methods will recall the sorry result, and be prepared to

appreciate Signor Lo Bianco's wonderfully beautiful specimens.

Naturalists have come from all over the world to Naples to learn "just

how" the miracle is accomplished, for it must be understood that the

mere citation of the _modus operandi_ by no means enables the

novitiate to apply it successfully at once. In the case of some of the

long-drawn-out forms of clustered ascidians and the like, the delicacy

of manipulation required to make successful preservations raises the

method as practised at Naples almost to the level of a fine art. It is

a boon to naturalists everywhere that the institution here is able

sometimes to supply other laboratories less favorably situated with

duplicates from its wealth of beautifully preserved specimens.

METHODS AND RESULTS

These, then, are some of the material conditions that have contributed

to make the results of the scientific investigations at the Naples

laboratory notable. But of course, even with a superabundance of

material, discoveries do not make themselves. "Who uses this material?"

is, after all, the vital question. And in this regard the laboratory

at Naples presents, for any one who gets at its heart, so to speak, an

ensemble that is distinctive enough; for the men who work in the light

and airy rooms of the laboratory proper have come for the purpose from

all corners of the civilized globe, and not a few of them are men of

the highest distinction in their various lines of biological science.

A large proportion are professors in colleges and universities of their

various countries; and for the rest there is scarcely one who is not

in some sense master of the biological craft. For it must be understood

that this laboratory at Naples is not intended as a training-school for

the apprentice. It offers in the widest sense a university course in

biology, and that alone. There is no instructor here who shows the

new-comer how to use the microscope, how to utilize the material, how

to go about the business of discovery. The worker who comes to Naples

is supposed to have learned all these things long before. He is

merely asked, then, what class of material he desires, and, this being

furnished him, he is permitted to go his own way unmolested. He may work

much or little, or not at all; he may make epochal discoveries or no

discoveries of any sort, and it will be all one to the management. No

one will ask him, in any event, what he has done or why he has not done

otherwise. In a word, the worker in the laboratory here, while being

supplied with opportunities for study such as he could hardly find

elsewhere, retains all the freedom of his own private laboratory.

Little wonder, then, that it is regarded as a rare privilege to be

allowed to work in this laboratory. Fortunately, however, it is a

privilege that may be obtained by almost any earnest worker who, having

learned the technique of the craft elsewhere, desires now to prosecute

special original studies in biology. Most of the tables here are leased

in perpetuity, for a fixed sum per annum, by various public or private

institutions of different countries. Thus, for example, America has the

right of use of several tables, the Smithsonian Institution leasing one,

Columbia University another, a woman's league a third, and so on. Any

American desiring to work at Naples should make application to one of

these various sources, stating the exact time when he would like to

go, and if there be a vacancy for that time the properly accredited

applicant is almost sure to receive the privilege he asks for. Failing

in this, however, there is still a court of last appeal in Dr. Dohrn

himself, who may have a few unoccupied tables at his disposal, and who

will surely extend the courtesy of their occupancy, for a reasonable

period, to any proper applicant, come he whence he may.

Thus it chances that one finds men of all nations working in the Naples

laboratory--biologists from all over Europe, including Russia, from

America, from Australia, from Japan. One finds women also, but these,

I believe, are usually from America. Biologists who at home are at the

head of fully equipped laboratories come here to profit by the wealth

of material, as well as to keep an eye upon the newest methods of their

craft, and to gain the inspiration of contact with other workers in

allied fields. Many of the German university teachers, for example, make

regular pilgrimages to Naples during their vacations, and more than one

of them have made the original investigations here that have given them

an international reputation.

As to the exact methods of study employed by the individual workers

here, little need be said. In this regard, as in regard to instrumental

equipment, one biological laboratory is necessarily much like another,

and the general conditions of original scientific experiment are pretty

much the same everywhere. What is needed is, first, an appreciation of

the logical bearings of the problem to be solved; and, secondly, the

skill and patience to carry out long lines of experiments, many of which

necessarily lead to no tangible result. The selection of material for

the experiments planned, the watching and cultivating of the living

forms in the laboratory tanks, the cutting of numberless filmy sections

for microscopical examination--these things, variously modified for each

case, make up the work of the laboratory student of general biology.

And just in proportion as the experiments are logically planned and

carefully executed will the results be valuable, even though they be but

negative. Just in proportion as the worker, by inclusion and exclusion,

attains authentic results--results that will bear the test of

repetition--does his reputation as a dependable working biologist become

established.

The subjects attacked in the marine laboratory first and last are

practically coextensive with the range of general biology, bacteriology

excepted. Naturally enough, the life histories of marine forms of

animals and plants have come in for a full share of attention. But, as I

have already intimated, this zoological work forms only a small part of

the investigations undertaken here, for in the main the workers prefer

to attack those general biological problems which in their broader

outlines apply to all forms of living beings, from highest to lowest.

For example, Dr. Driesch, the well-known Leipzig biologist, spends

several months of each year at the laboratory, and has made here most of

those studies of cell activities with which his name is associated.

The past season he has studied an interesting and important problem of

heredity, endeavoring to ascertain the respective shares of the male and

female parents in the development of the offspring. The subjects of his

experiments have been various species of sea-urchins, but the principles

discovered will doubtless be found to apply to most, or perhaps all,

forms of vertebrate life as well.

While these studies were under way another developmental problem was

being attacked in a neighboring room of the laboratory by Professor

Kitasato, of the University of Tokio, Japan. The subjects this time were

the embryos of certain fishes, and the investigation had to do with

the development of instructive monstrosities through carefully designed

series of injuries inflicted upon the embryo at various stages of its

development. Meantime another stage of the developmental history of

organic things--this time a microscopical detail regarding the cell

divisions of certain plants--has been studied by Professor Mottier,

of Indiana; while another American botanist, Professor Swingle, of

the Smithsonian Institution, has been going so far afield from

marine subjects as to investigate the very practical subject of the

fertilization of figs as practised by the agriculturists about Naples.

Even from these few citations it will appear how varied are the lines of

attack of a single biological problem; for here we see, at the hands

of a few workers, a great variety of forms of life--radiates, insects,

vertebrates, low marine plants and high terrestrial ones--made to

contribute to the elucidation of various phases of one general topic,

the all-important subject of heredity. All these studies are conducted

in absolute independence, and to casual inspection they might seem to

have little affinity with one another; yet in reality they all trench

upon the same territory, and each in its own way tends to throw light

upon a topic which, in some of its phases, is of the utmost practical

importance to the human family. It is a long vault from the embryo of

an obscure sea-weed to the well-being of man, yet it may well happen--so

wide in their application are the general life principles--that study of

the one may point a practical moral for the other.

Indeed, it constantly happens that the student of biology, while

gazing through his microscope, hits upon discoveries that have the most

far-removed implications. Thus a few years ago it was discovered that

when a cell is about to bisect itself and become two cells, its nucleus

undergoes a curious transformation. Within the nuclear substance little

bodies are developed, usually threadlike in form, which take on a deep

stain, and which the biologist calls chromosomes. These chromosomes vary

in number in the cells of different animals, but the number is always

the same for any given species of animal. If one were to group animate

beings in classes according to this very fundamental quality of the

cells he would have some very curious relations established. Thus, under

the heading "creatures whose cells have twenty-four chromosomes," one

would find beings so different as "the mouse, the salamander, the trout,

and the lily," while the sixteen-chromosome group would introduce the

very startling association of the ox, the guinea-pig, the onion, and man

himself. But whatever their number, the chromosomes are always exactly

bisected before the cell divides, one-half being apportioned to each of

the two cells resulting from the division.

Now the application is this: It was the study of these odd nuclear

structures and their peculiar manouvrings that, in large measure, led

Professor Weismann to his well-known theory of heredity, according

to which the acquired traits of any being are not transmissible to the

offspring. Professor Weismann came to believe that the apportionment

of the nuclear substance, though quantitatively impartial, is sometimes

radically uneven in quality; in particular, that the first bisection

of the egg-cell, which marks the beginning of embryonic development,

produces two cells utterly different in potentiality, the one containing

the "body plasm," which is to develop the main animal structures, the

other encompassing the "germ plasm," by which the racial integrity is

[to be preserved. Throughout the life of the individual, he believed,

this isolation continued; hence the assumed lack of influence of

acquired bodily traits upon the germ plasm and its engendered offspring.

Hence, also, the application of the microscopical discovery to the

deepest questions of human social evolution.

Every one will recall that this theory, born of the laboratory, made

a tremendous commotion in the outside world. Its application to the

welfare and progress of humanity gave it supreme interest, and polemics

unnumbered were launched in its favor and in its condemnation. Eager

search was made throughout the fields of botany and zoology for new

evidence pro or con. But the definitive answer came finally from the

same field of exploration in which the theory had been originated--the

world of the cell--and the Marine Biological Laboratory was the seat of

the new series of experiments which demonstrated the untenability of the

Weismannian position. Most curious experiments they were, for in effect

they consisted of the making of two or more living creatures out of one,

in the case of beings so highly organized as the sea-urchins, the

little fishlike vertebrate, amphioxus, and even the lower orders of true

fishes. Of course the division of one being to form two is perfectly

familiar in the case of those lowly, single-celled creatures such as the

protozoa and the bacteria, but it seems quite another matter when one

thinks of cutting a fish in two and having two complete living fish

remaining. Yet this is virtually what the biologists did.

Let me hasten to add that the miraculous feat was not accomplished

with an adult fish. On the contrary, it is found necessary to take the

subject quite at the beginning of its career, when it consists of an

egg-cell in the earliest stages of proliferation. Yet the principle is

quite the same, for the adult organism is, after all, nothing more

than an aggregation of cells resulting from repeated divisions (growth

accompanying) and redivisions of that original egg-cell. Considering

its potentialities, the egg-cell, seemingly, is as much entitled to be

considered an individual as is the developed organism. Yet it transpires

that the biologist has been able so to manipulate a developing egg-cell,

after its bisection, that the two halves fall apart, and that each half

(now become an independent cell) develops into a complete individual,

instead of the half-individual for which it seemed destined. A

strange trick, that, to play with an individual _Ego_, is it not?

The traditional hydra with its reanimating heads was nothing to this

scientific hydra, which, when bisected bodily, rises up calmly as two

whole bodies.

But even this is not the full measure of the achievement, for it has

been found that in some cases the experiment may be delayed until the

developing egg has made a second bisection, thus reaching the four-cell

stage, when four completely formed individuals emerge from the

dismembered egg. And in the case of certain medusae, success has

attended experiments made at the eight-cell and even at the sixteen-cell

stage of development, the creature which had got thus far on its career

in single blessedness becoming eight or sixteen individuals at the wave

of the enchanted wand--that is to say, the dissecting-needle--of

the biologist. All of which savors of conjury, but is really only

matter-of-fact biological experiment--experiment, however, of which

the implications by no means confine themselves to matters of fact

biological. For clearly the fact that the separated egg-cells grow into

complete individuals shows that Weismann's theory, according to which

one of the cells contained only body plasm, the other only germ plasm,

is quite untenable. Thus the theory of the non-transmissibility of

acquired characters is deprived of its supposed anatomical support and

left quite in the air, to the imminent peril of a school of sociologists

who had built thereon new theories of human progress. Also the question

of the multiplied personalities clearly extends far beyond the field

of the biologist, and must be turned over to the consideration of the

psychologist--if, indeed, it does not fall rather within the scope of

the moralist.

But though it thus often chances that the biologist, while gazing

stoically through his microscope, may discover things in his microcosm

that bear very closely upon the practical interests of the most

unscientific members of the human family, it would be a mistake to

suppose that it is this class of facts that the worker is particularly

seeking. The truth is that, as a rule, the pure biologist is engaged in

work for the love of it, and nothing is further from his thoughts than

the "practical" bearings or remote implications of what he may discover.

Indeed, many of his most hotly pursued problems seem utterly divorced

from what an outsider would call practical bearings, though, to be

sure, one can never tell just what any new path may lead to. Such, for

example, is the problem which, next to questions of cell activities,

comes in for perhaps as large a share of attention nowadays as any other

one biological topic;--namely, the question as to just which of

the various orders of invertebrate creatures is the type from which

vertebrates were evolved in the past ages--in other words, what

invertebrate creature was the direct ancestor of the vertebrates,

including man. Clearly it can be of very little practical importance to

man of to-day as to just who was his ancestor of several million years

ago. But just as clearly the question has interest, and even the layman

can understand something of the enthusiasm with which the specialist

attacks it.

As yet, it must be admitted, the question is not decisively answered,

several rival theories contending for supremacy in the case. One of

the most important of these theories had its origin at the Naples

laboratory; indeed, Dr. Dohrn himself is its author. This is the view

that the type of the invertebrate ancestor is the annelid--a form whose

most familiar representative is the earth-worm. The many arguments for

and against accepting the credentials of this unaristocratic ancestor

cannot be dwelt upon here. But it may be consolatory, in view of the

very plebeian character of the earth-worm, to know that various of the

annelids of the sea have a much more aristocratic bearing. Thus the

filmy and delicately beautiful structures that decorate the pleasant

home of the quaint little seahorse in the aquarium--structures having

more the appearance of miniature palm-trees than of animals--are really

annelids. One can view Dr. Dohrn's theory with a certain added measure

of equanimity after he learns this, for the marine annelids are seen,

some of them, to be very beautiful creatures, quite fitted to grace

their distinguished offspring should they make good their ancestral

claims.

These glimpses will suffice, perhaps, to give at least a general idea of

the manner of thing which the worker at the marine laboratory is seeking

to discover when he interrogates the material that the sea has given

him. In regard to the publication of the results of work done at the

Naples laboratory, the same liberal spirit prevails that actuates the

conduct of the institution from first to last. What the investigator

dis* covers is regarded as his own intellectual property, and he

is absolutely free, so far as the management of this institution is

concerned, to choose his own medium in giving it to the world. He may,

and often does, prefer to make his announcements in periodicals or books

issued in his own country and having no connection whatever with the

Naples laboratory. But, on the other hand, his work being sufficiently

important, he may, if he so desire, find a publisher in the institution

itself, which issues three different series of important publications,

under the editorship of Professor Mayer.

One of these, entitled _Mittheilungen aus der Zoologische Station

zu Neapel_, permits the author to take his choice among four

languages--German, English, French, or Italian. It is issued

intermittently, as occasion requires. The second set of publications

consists of ponderous monographs upon the fauna and flora of the Gulf

of Naples. These are beautifully illustrated in color, and sometimes a

single volume costs as much as seventeen thousand dollars to issue. Of

course only a fraction of that sum is ever recovered through sale of the

book. The third publication, called _Zoologischen Jahresbericht_, is a

valuable résumé of biological literature of all languages, keeping the

worker at the laboratory in touch with the discoveries of investigators

elsewhere.

The latter end is attained further by the library of the institution,

which is supplied with all the periodicals of interest to the biologist

and with a fine assortment of technical books. The library-room, aside

from its printed contents, is of interest because of its appropriate

mural decorations, and because of the bronze portrait busts of the two

patron saints of the institution, Von Baer and Darwin, which look down

inspiringly upon the reader.

All in all, then, it would be hard to find a deficiency in the Stazione

Zoologica as an instruement of biological discovery. A long list might be

cited of the revelations first brought to light within its walls. And

yet, as it seems to me, the greatest value of this institution as an

educational factor in science--as a biological lever of progress--does

not depend so much upon the tangible revelations of fact that have come

out of its laboratories as upon other of its influences. Scientific

ideas, like all other forms of human thought, move more or less in

shoals. Very rarely does a great discovery emanate from an isolated

observer. The man who cannot come in contact with other workers in

kindred lines becomes more or less insular, narrow, and unfitted for

progress. Nowadays, of course, the free communication between different

quarters of the globe takes away somewhat from the insularity of any

quarter, and each scientist everywhere knows something of what the

others are doing, through wide-spread publications. But this can never

altogether take the place of personal contact and the inspirational

communication from man to man. Hence it is that a rendezvous, where all

the men of a craft go from time to time and meet their fellows from all

over the world, has an influence for the advancement of the guild

which is enormous and unequivocal, even though difficult of direct

demonstration.

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 assigned 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 massed numbers. Presently some one suggests

to the new-comer that he join some of the others of a Wednesday or

Saturday 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 confrères of the

laboratory gathered about a long table, with the most conglomerate

groups of Neapolitans of a seemingly doubtful class 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 institution; 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

séances 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 associations 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 institutions 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 institution despite

its location.

The American stations are located at Woods' Holl and at Cold Spring

Harbor, on opposite coasts of Long Island Sound. The Japanese 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