Rodolfo Amedeo Lanciani.

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Erecisely the same reason as a tub of fermenting beer is capa-
le of propagating its fermentation by " infection," or " conta-
gion,'^ to fresh wort In both cases it is the solid living parti-
cles which are efficient ; the liquid in which they float, and at
the expense of which they live, being altogether passive.

Now arises the question, are these microzymes the results of
Horrwgenesis, or of Xenogenesis ; are they capable, like the To-

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898 Address of Professor Huxky.

ntke of yeast, of arising only by the development of preexist-
ing germs ; or may they be, like the constituents of a nutgall,
the results of a modification and individualization of the tissues
of the body in which they are found, resulting from the opera-
tion of certain conditions r Are thejr parasites in the zomogi-
cal sense, or are they merely what Virchow has called " hetero-
logous growth?" ft is obvious that this q^uestion has the most
profound importance, whether we look at it from a practical or
irom a theoretical point of view. A parasite may be stamped
out bv destroying its germs, but a pathological product can
only be annihilated by removing the conditions which give rise
to it

It appears to me that this great problem will have to be solved
for each zymotic disease separately, for analog cuts two ways.
I have dwelt upon the analogy of pathologi<^ modification,
which is in favor of the xenogenetic origin oi microzymes ; but
I must now speak of the equally strong analogies m favor of
the origin of such pestiferous particles by the ordinary process
of the generation of like from lika

It is, at present, a well-established &ct that certain diseases^
both of plants and of animals, which have all the characters of
contagious and infectious epidemics, are caused by minute or-
ganisma The smut of wheat is a well-known instance of such
a disease, and it cannot be doubted that the grape-disease and
the potato-disease fall under the same categoiy. Among ani-
mals, insects are wonderfully liable to the ravages of contagious
and infectious diseases caus^ by microscopic Fungi

In autumn, it is not uncommon to see flies, motionless upon a
window-jpane, with a sort of inagic circle, in white, drawn round
theuL On microscopic examination^ the magic circle is found
to consist of innumerable spores, which have been thrown off in
all directions by a minute fundus called Mnpusa mtiscce, tie
spore-forming filaments of which stand out like a pile of velvet
from the body of the fly. These spore-forming nlaments are
connected with others which fill the interior of the fly*s body
like so much fine wool, having eaten away and destroyed the
creature's viscera. This is tne full-grown condition of the
Empusa. If traced back to its earlier stages, in flies which are
still active, and to all appearance healthy, it is found to exist in
the form of minute corpuscles which float in the blood of the
fly. These multiply and lengthen into filaments, at the expense
of the fly^s substance ; and when they have at last killea the
patient, they grow out of its body and give off spores. Healthy
flies shut up with diseased ones catch this mortal disease and
perish like the others. A most competent observer, M. Cohn,
who studied the development of the Empusa in the fly very
carefully, was utterly unable to discover in what manner the

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Address of Professor Huxley. 899

smallest germs of the Empwsa got into the fly. The spores
could not be made to give rise to such germs by cultivation ;
nor were such germs discoverable in the air, or in the food of
the fly. It lo(3ced exceedingly like a case of Abiogenesis, or,
at any rate, of Xenogenesis ; and it is only quite recently that
the real course of events has been maae out It has been
ascertained, that when one of the spores fells upon the body of
a fly, it b^ins to germinate and sends out a process which bores
its way through the fly's skin ; this, having reached the interior
cavities of its body, gives off the minute floating corpuscles
which are the earliest stage of the Emptiscu The disease is
"contaffious," because a healthy fly coming in contact with a
diseased one, from which the spore-bearing filaments protrude,
is pretty sure to carry off a spore or two. It is "infectious"
because the spores become scattered about all sorts of matter in
the neighborhood of the slain flies.

The silkworm has long been known to be subject to a very
fetal and infectious disease called the Muscardine, Audouin
transmitted it by inoculation. This disease is entirely due to
the development of a fiingus, Botrytis Bassiana^ in the body of
the caterpiller; and its contagiousness and infectiousness are
accoimtea for in the same way as those of the fly-disease. But
of late years a still more serious epizootic has appeared among
the silkworms ; and I may mention a few fects which mil give
you some conception of tne gravity of the injury which it has
mflicted on Prance alona

The production of silk has been for centuries an important
branch of industry in Southern France, and in the year 1858 it
had attained such a magnitude that the annual produce of the
French sericulture was estimated to amount to a tenth of that
of the whole world, and represented a money- value of 117,000,000
of francs, or nearly five million sterling. What may be the sum
which would represent the money -value of all the industries
connected with tne working up of the raw silk thus produced
is more than I can pretend to estimate. Suffice it to say that
the city of Lyons is built upon French silk as much as Man-
chester was upon American cotton before the civil war.

Silkworms are liable to many diseases ; and even before 1858
a peculiar epizootic, frequently accompanied by the appearance
of dark spots upon the skin (whence the name of "Purine"
which it has recdved), had been noted for its mortality. But
in the years following 1858 this malady broke out with such
extreme violence, that, in 1858, the silk-crop was reduced to a
third of the amount which it had reached in 1858 ; and, up till
within the last year or two, it has never attained half the yield
of 1858. This means not only that the great number of people
engaged in silk growing are some thirty millions sterling poorer
than they might have been ; it means not only that hign prices

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400 Address of Professor Hvxky.

have had to be paid for importing silkworm eggs, and that, after
investing his money in them, in paying for mulberry-leaves and
for attendance, the cultivator has constantly seen his silkworms
perish and himself plunged in ruin ; but it means that the looms
of Lyons have lacked employment, and that for yesas enforced
idleness and miserv have oeen the portion of a vast population
which, in former aays, was industnous and well to do.

In 1868 the gravity of the situation caused the French Acad-
emy of Sciences to appoint Commissioners, of whom a distin-
guished naturalist, M. de Quatrefeges, was one to inquire into
Uie nature of this disease, and, if possible, to devise some means
of staying the plagua In reading the report* made by M. de
Quatrefiages in 1869, it is exceedingly interesting to observe that
Ins elaborate study of the Purine forced the conviction upon
his mind that, in its mode of occurrence and propa^tion, the
disease of the silkworm is, in every respect, comparaole to the
cholera among mankind But it dififers from the cholera, and
so far is a more formidable disease, in being hereditary, and in
being imder some circumstances, contagious as well as in-

The Italian naturalist, Filippi, discovered in the blood of the
silkworms aflfected by the strange disease a multitude of cvlin-
drical corpuscles, each about ^ Vj^^ of an inch long. These have
been carerully studied by Lebert, and named by him PomsisUh
phyton ; for the reason that in subjects in which the disease is
strongly developed, the corpuscles swarm in every tissue and
organ of the bcniy, and even pass into the undeveloped ^gs of
the female moth. But are these corpuscles causes, or mere con-
comitants, of the disease? Some naturalists took one view and
some another ; and it was not imtil the French Government,
alarmed by the continued ravages of the malady, and the in-
efficiency of the remedies which had been suggested, dispatched
M. Pasteur to study it, that the question received its final settle-
ment ; at a great sacrifice, not only of the time and peace of
mind of that eminent philosopher, but, I regret to have to add,
of his healtLf

But the sacrifice has not been in vain. It is now certain that
this devastating, cholera-like Purine is the effect of the growth
and mutiplication of the Panhistophyion in the silkworm. It is
contagious and infections because the corpuscles of the Panhisto-
phyton pass away fi'om the bodies of the diseased caterpillars,
directly or indirectly, to the alimentary canal of healthv silk-
worms in their neignborhood ; it is hereditary, because the cor-
puscles enter into the eggs while they are oeing formed, and
consequently are carried within them when they are laid ; and

* Ettides Rur len Maladies ActueUes des Ters i Sole, p. 53.
f In Nature Na xxxvi, p. 181, will be found a HmtnU^ by Prof. TyndaU, of
Pasteur's investigations of the silkworm disease.

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Address of Professor Huxley. 401

for this reason, also, it presents the very singular peculiarity
of being inherited only on the mother's sida There is not a
single one of all the apparently capricious and unaccountable
phenomena presented by the Pdbrine, but has received its ex-
planation from the fact that the disease is the result of the pres-
ence of the microscopic organism, Panhistophyton.

Such being the facts with respect to the Purine, what are
the indications as to the methoa of preventing it? It is ob-
vious that this depends upon the way in which the Panhisto-
phyton is generat€«. K it may be generated by Abiogenesis,
or by Xenogenesis, within the silkworm or its moth, the extir-
pation of the disease must depend upon the prevention of the
occurrence of the conditions under which this generation takes
place. But i^ on the other hand, the Panhistophyton is an
mdependent organism, which is no more generated oy the silk-
worm than the mistletoe is generated by the oak or the apple-
tree on which it grows, though it may need the silkworm writs
development in the same wav as the mistletoe needs the tree,
then the indications are totally different The sole thing to be
done is to get rid of and keep away the germs of the Panhisto-
phyton. As might be imagined, fix)m the course of his previous
investigations, M. Pasteur was led to believe that the latter was
the right theory; and, ^ided by that theory, he has devised a
method of extirpating the disease, which has proved to be com-
pletely successful wherever it has been properly carried out

There can be no reason, then, for doubting that, among in-
sects, contagjious and infectious diseases, of great malignity, are
caused by minute organisms which are produced fk>m preexisting
germs, or by homogenesis ; and there is no reason, that I know
of, for believing that what happens in insects may not take
place in the highest animals. Indeed, there is already strong
evidence that some diseases of an extremely malignant and fatal
character to which man is subject, are as much the work of mi-
nute organisms as is the Purine. I refer for evidence of this to
the very striking facts adduced by Professor Lister in his various
well-known publications on the antiseptic method of treatment
It seems to me impossible to rise ftx)m the perusal of those pub-
lications without a strong conviction that the lamentable mor-
tality which so frequently dogs the footsteps of the most skillful
operator, and those deadly conseauences of wounds and injuries
which seem to haunt the very walls of great hospitals, and are,
even now, destroying more men than die of bullet or bayonet,
are due to the importation of minute organisms into wounds,
and their increase and multiplication ; and that the surgeon
who saves most lives will be ne who best works out the practi-
cal consequences of the hypothesis of Redi.

I commenced this Addi^Ms by asking you to follow me in an
attempt to trace the path which has been followed by a scientific

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402 Address of Professor Huxley.

idea, in its long and slow progress from the position of a probable
hypothesis to that of an established law of nature. Our survey
has not taken us into very attractive r^ons ; it has lain, chiefly,
in a land flowing with the abominable, and peopled with mere
grubs and mouloiness. And it may be imagined with what smiles
and shrugs, practical and serious contempcouries of Bedi and of
Spallanzani may have commented on the waste of their high abU-
ities in toiling at the solution of problems which, though curious
enough in themselves, could be of no conceivable utility to man-
kind. Nevertheless you will have observed that before we had
traveled very far upon our road there appeared, on the ri^it
hand and on the len^ fields laden with a luurest of golden grain,
inmiediately convertible into those things which the most sordidly
practical of men will admit to have value, viz : money and lifa

The direct loss to France caused by the Purine in seventeen
years cannot be estimated at less than fifty millions steriing ; and
if we add to this what Redi's idea, in Pasteur's hands, has done
for the wine-grower and for the vinegar-maker, and try to capi-
talise its value, we shall find that it will go a long way towards
repairing the money losses caused by the frightful and calami-
tous war of this autumn. And as to the equivalent of Bedi's
thought in life, how can we over-estimate the value of tiiat knowl-
edge of the nature of epidemic and epizootic diseases, and con-
sequently of the means of checking, or eradicating, them, the
dawn of which has assuredly commenced ?

Looking back no frirther than ten years, it is possible to select
three (1863, 1864, and 1869) in which the total number of
deaths from scarlet-fever alone amounted to ninety thousand.
That is the return of killed, the maimed and disable being 1^
out of sight Why, it is to be hoped that the list of killed in
the present bloodiest of all wars will not amount to more than
this I But the facts which I have placed before you must leave
the least sanguine without a doubt that the nature and the causes
of this scourge will, one day, be as well understood as those of
the Pdbrine are now ; and that the long-suflfered massacre of our
innocents will come to an end.

And thus mankind will have one more admonition that " the
people perish for lack of knowledge ;" and that the alleviation
of the miseries, and the promotion of the welfare, of men must
be sought, by those who will not lose their pains, in that dili-

fent, patient, loving study of all the multitudinous aspects of
Tature, the results of which constitute exact knowledge, ot
Scienca It is the justification and the glory of this great
meeting that it is gathered together for no other object thaii the
advancement of the moiety of science which deals with those
phenomena of nature which we call physical May its endeav-
ors be crowned with a fall measure of success.

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H. a Havey on the HaOstorm of June, 1870. 403

Art. XIAY. — The HaU'Storm of June 20th, 1870; by Rev.
Horace C. Hovey, M.A.

This remarkable storm swept along a path about thirty miles
wide, and extending from Troy, N. i., to Bangor, Me., though
it was not everywhere accompanied bv hail

My point of observation was in Northampton, Mass., which
was in the central line of the storm.

At sunrise the atmosphere was obscured by fog, which was
partially dispersed at a later hour. The day was sultry. At
noon the thermometer indicated 88° in the shade. At 3 P. M.
a vast mass of dark-green cloud rolled up from the N. W.,
while lateral currents seemed to set in, forcing the clouds at
first into confusion, but aiterwards into a well-defined vortex,
or spout The electrical detonations were frequent and sharp.
No rain preceded the hail, though it fell copiousl v after a few
minutes. The first hail-stones were about one inch in diameter,
and seemed to fall fix)m a greater height, and with more force,
than those that fell subsequently. The latter were probably
nearer the center of the vortex, and so had their downwam
motion restrained by that which was lateral The first that fell
were, most of them, on striking the ground, instantiy buried
out of sight If they struck on a rocky surface they were
dashed in pieces, or else rebounded to a considerable height in
in the air. Had their larger successors been driven by a cor-
responding force, nothing could have survived their assault
The smaller hail-stones were generally flattened spheres, though
sometimes in rude stellar forms, (fig. 1). But the largest ones
were symmetrical ovoids ; each being surmounted, however, by
a roughened crown, (fig. 2). The dimensions and weight of

1. 2. H"X2i"- 3. 2"diam.

three specimens are given, with such accuracy as could be
secured^ by the means at hand. These are but samples of
thousands that fell till tiie earth was covered with ice. The
first was, in long diameter, 3f inches ; short diameter, 2^ inches ;
weight 7 ounces. The second was 3i inches by 2i ; weight
8 ounces. The third was 4 inches by 2|; weight 10 ounces.

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404 C, A. Young — Photograph of a Solar Prominence.

This monster, a foot in circumference, did not entirely melt
away for six hours after it fell I The ice in all the hail-stones
was peculiarly hard and compact Interesting structural pecu-
liarities were noted. Hail-stones of stellar form were always
transparent and homogeneous. The spheroids were covered
with an opaque coating, and had likewise an opaque center.
On being bisected some of them showed a radiated structure,
the alternate rays being white and clear, (fig. 3). The largest
hail-stones had an axis of white ice, half an inch in diameter,
around which the alternate layers were arranged in spiral con-

6. 3" diam.
4. 3i" X 2i".

volutions, (fiff. 4). The most common form was in concentric
layers, like the coats of an onion, still aJtemating opaque and
transparent ; but the edges were finely serrated, like the stripes
in some species of agate, (fig. 5). In one hailstone I counted
thirteen of these layers, indicating that it had passed through
as many strata of snowy and vaporous cloud.

After a lull in the storm, for half an hour, there was a second
fall of hail, but much lighter than the first

The damage done by such a war of the elements cannot
easily be ascertained. V egetation suffered greatly. In some
cases men and animals were wounded The icy missies not
only broke thousands of pains of glass, but also in many in-
stances the window-blinds and sasL In a few cases weather-
worn house-roofe were pierced.

Peoria, UL, July 26, 1870.

Abt. XLV. — Photograph of a Solar Prominence; by Prof C. A.
Young, of Dartmouth College.

The following is fixjm a letter to the editors dated Sept 28th,
1870 :—

I have just succeeded, with the help of our skillfiil artist Mr.
H. O. Bly, in obtaining a photograph of one of the solar prom-
inences, a copy of which I enclose. It was taken through the

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A. K VerriU on New England Nudvbranchiaia, 405

hydrogen line, near G, by opening the slit of the spectroscope
and attaching a small camera to its eye-piece. As a picture of
course it amounts to very littla It required an exposure of
three minutes and a half^ and the polar axis of the telescope
being imperfectly adjusted, the clock-work fiadled to follow per-
fectly, so that no detoil is visible, and the picture will not bear
mucn ma^ifyinff. I am convinced, however, that by using a
more sensitive cdlodion, and taking proper pains with the ad-
justment of the instrument, satisfactory photographs of these
curious objects may be obtained

I may add that the spectroscope employed has the dispersive
power of 13 prisms of mnt, each with an angle of 55°.

With it I observed this afternoon in the spectrum of a spot,
the reversal of the following lines, viz : C, Di, Dg, Dj, 1474 K,
(very faint), 6i, 6^ 6„ 64, F, 2796 K, (Hy), and h (H^). b^ was
most conspicuous after Cj, D3, and R

Abt. XTjVL — Qmtnbuticns to Zoology from the Museum of Tale
College. No. 8. — Descriptions of some New England Nudibran-
chiata ; by A. K Verrill.

During a dredging expedition to Eastport, Ma, and Grand
Menan, the past season, in company with Mr. Oscar Harger and
C. H. Dwinelle, students in the Sneffield Scientific School, the
following very interesting species was obtained. Many other
Nudibranchs were also observed, most of which are well known

Dendronotus robustus, sp. nov. Figure 1.

Body stout, about 2 inches long; -5 broad, and about the
same m height, somewhat (juadrangular, tapering posteriorly,
but much less acute than m D. aroorescevs^ as well as much
stouter throughout Branchiae in about six pairs, those of the
three first pairs with a supplementary one of nearly the same
size arising separately outsiae o^ but close to their bases ; on
the fourth pair these originate from the base as large branches,
and on the following ones they are more distinctly branches,
arising from the sides near the bases of the branchiae. The
branchiae are difiusely arborescent and very much subdivided,
the divisions taking place very rapidly, the branches being
more equal in length and more spreading than in D, arborescens,
and do not have the long, slender and acute main branches seen
in that species. The sheaths of the tentacles (figure 1, a) are
round and stout, about 4 of an inch long and -12 in diameter,
and are destitute of any lateral branches ; they divide at top
into five simple, roirnd, smooth, tapering, acute divisions, of
which the two posterior ones are longest The tentacles (figure

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406 A. E, Verrill on New EngUmd NudtbranchiaicL

1, b) are about equal in length to the lobes of the sheath,
the pedicle forming about half of the visible part ; the terminal
portion suddenly enlai^es at first, becomes somewhat conical,
and tapers to an obtuse point; it has ten or twelve oblique
plicationa Front of head with numerous (about l
thirty) sparingly branched appendages arranged in
two series. In the upper series there are about
ten, the outer ones beinff largest ; these have stout
stems with a few conical, tapering branches, mostly
on the lower side, which are tipped with sulphur-
yellow. Below these are numerous unequal, small-
er, and more simple appendages, about ten on each
side, part of which are forked at the end, while others
are simple and papilliform and surround the expan-
ded oral disk ; all are tipped with yellow. The oral
disk (figure 1, c) is tranversely elliptical The foot is
nearly as broad as the bodv ('4: of an inch), and can be adapted
for clasping by infolding tne edges.

Color pale grayish, thickly sprinkled with small yellow spots,
which become less numerous on the oral appendages and
sheaths of the tentacles.

Whale Cove, Grand Menan, on sea- weeds in a pool near low-
water mark One specimen only, found by Mr. Oscar Harg^.

Dendronotus arborescens Alder and Hancock {V. BeynoldsU
Couthouy) differs widely fix)m this species in having a very
narrow foot; an elevated compressed body, which is more
slender and more acute behind ; a much smaller number (about
ten or twelve) appendages in front of the head, of which the six
upper ones are larger and much more branched, and the four
lower ones very small ; the gills longer and the branches more
unequal, while the lowest branch on the outside arises from the
side, above the base, even on the front pairs ; and in having
more clavate tentacles, with longer and branched lobes to their
sheaths, while the sheaths also have a large, arborescent, gUl-
like branch driginating from the outer side toward the base. By
the last character alcoholic specimens can easily be distinguishei
Both species occurred togetner in the same pooL

Doris bifida^ sp. nov.

Outline broad oval, widest anteriorly, 1 inch long by '5 broad,
in extension, back very convex, mantle covered with numerous,
scattered, prominent, pointed papillfiD. Tentacles rather long,
thickest in the middle, the outer half strongly plicated, but wiSi
a smooth tip, the base surrounded by small papill». Gills re-
tractile into a single cavity, united together by a partial web,

Online LibraryRodolfo Amedeo LancianiThe American journal of science and arts → online text (page 99 of 109)