THE STARRY HEAVENS 373
The Moon 377
The Sun 382
The Planets 387
Mercury 388
Venus 390
The Earth 391
Mars 392
The Minor Planets 393
Jupiter 394
Saturn 395
Uranus 396
Neptune 397
Origin of the Planetary System 398
Comets 401
Shooting Stars 406
The Stars 410
Nebulæ 425
ILLUSTRATIONS
FIG. PAGE
1. Larva of Choerocampa porcellus 53
2. Bougainvillea fruticosa; natural size. (After Allman) 107
3. Do. do. magnified 108
4. Do. do. Medusa-form 109
5. Medusa aurita, and progressive stages of development.
(After Steenstrup) 110
6. White Dead-nettle 124
7. Do. 125
8. Do. 125
9. Salvia 127
10. Do. 127
11. Do. 127
12. Primrose 131
13. Do. 131
14. Arum 135
15. Twig of Beech 140
16. Arrangement of leaves in Acer platanoides 142
17. Diagram to illustrate the formation of Mountain Chains 216
18. Section across the Jura from Brenets to Neuchâtel. (After Jaccard) 219
19. Section from the Spitzen across the Brunnialp, and the
Maderanerthal. (After Heim) 221
20. Glacier of the Blümlis Alp. (After Reclus) 228
21. Cotopaxi. (After Judd) 237
22. Lava Stream. (After Judd) 239
23. Stromboli, viewed from the north-west, April 1874. (After Judd) 242
24. Upper Valley of St. Gotthard 257
25. Section of a river valley. The dotted line shows a slope or
talus of debris 260
26. Valley of the Rhone, with the waterfall of Sallenches, showing
a talus of debris 261
27. Section across a valley. _A_, present river valley; _B_, old
river terrace 262
28. Diagram of an Alpine valley, showing a river cone. Front view 263
29. Diagram of an Alpine valley, showing a river cone. Lateral view 265
30. Map of the Valais near Sion 266
31. View in the Rhone Valley, showing a lateral cone 267
32. Do. showing the slope of a river cone 268
33. Shore of the Lake of Geneva, near Vevey 269
34. View in the district of the Broads, Norfolk 271
35. Delta of the Po 273
36. Do. Mississippi 274
37. Map of the Lake District 281
38. Section of the Weald of Kent, _a, a_, Upper Cretaceous strata,
chiefly Chalk, forming the North and South Downs; _b, b_, Escarpment of
Lower Greensand, with a valley between it and the Chalk; _c, c_, Weald
Clay, forming plains; _d_, Hills formed of Hastings Sand and Clay. The
Chalk, etc., once spread across the country, as shown in the dotted
lines 283
39. Map of the Weald of Kent 284
40. Sketch Map of the Swiss Rivers 291
41. Diagram in illustration of mountain structure 296
42. Sketch Map of the Aar and its tributaries 299
43. River system round Chur, as it used to be 308
44. River system round Chur, as it is 309
45. River system of the Maloya 311
46. Final slope of a river 317
47. Do. do. with a lake 318
48. Diagrammatic section of a valley (exaggerated). _R R_, rocky basis of
a valley; _A A_, sedimentary strata; _B_, ordinary level of river;
_C_, flood level 329
49. Whitsunday Island. (After Darwin) 359
50. A group of Lunar volcanoes; Maurolycus, Barocius, etc.
(After Judd) 380
51. Orbits of the inner Planets. (After Ball) 388
52. Relative distances of the Planets from the Sun. (After Ball) 389
53. Saturn, with the surrounding series of rings. (After Lockyer) 395
54. The Parallactic Ellipse. (After Ball) 413
55. Displacement of the hydrogen line in the spectrum of Rigel.
(After Clarke) 416
PLATES
BURNHAM BEECHES _Frontispiece_
WINDSOR CASTLE. (From a drawing by J. Finnemore) _To face page_ 13
AQUATIC VEGETATION, RIO. (Published by Spooner and Co.) 145
TROPICAL FOREST, WEST INDIES. (After Kingsley) 179
SUMMIT OF MONT BLANC 203
THE MER DE GLACE, MONT BLANC 229
RYDAL WATER. (From a photograph by Frith and Co., published by
Spooner and Co.) 247
WINDERMERE 253
VIEW IN THE VALAIS BELOW ST. MAURICE 264
VIEW UP THE VALAIS FROM THE LAKE OF GENEVA 268
THE LAND'S END. (From a photograph by Frith and Co., published by
Spooner and Co.) 334
VIEW OF THE MOON NEAR THE THIRD QUARTER. (From a photograph by Prof.
Draper) 371
CHAPTER I
INTRODUCTION
If any one gave you a few acres, you would say that you had
received a benefit; can you deny that the boundless extent of
the earth is a benefit? If any one gave you money, you would
call that a benefit. God has buried countless masses of gold
and silver in the earth. If a house were given you, bright with
marble, its roof beautifully painted with colours and gilding,
you would call it no small benefit. God has built for you a
mansion that fears no fire or ruin ... covered with a roof
which glitters in one fashion by day, and in another by
night.... Whence comes the breath you draw; the light by which
you perform the actions of your life? the blood by which your
life is maintained? the meat by which your hunger is
appeased?... The true God has planted, not a few oxen, but all
the herds on their pastures throughout the world, and furnished
food to all the flocks; he has ordained the alternation of
summer and winter ... has invented so many arts and varieties
of voice, so many notes to make music.... We have implanted in
us the seed of all ages, of all arts; and God our Master brings
forth our intellects from obscurity.--SENECA.
CHAPTER I
INTRODUCTION
The world we live in is a fairyland of exquisite beauty, our very
existence is a miracle in itself, and yet few of us enjoy as we might,
and none as yet appreciate fully, the beauties and wonders which
surround us. The greatest traveller cannot hope even in a long life to
visit more than a very small part of our earth, and even of that which
is under our very eyes how little we see!
What we do see depends mainly on what we look for. When we turn our eyes
to the sky, it is in most cases merely to see whether it is likely to
rain. In the same field the farmer will notice the crop, geologists the
fossils, botanists the flowers, artists the colouring, sportsmen the
cover for game. Though we may all look at the same things, it does not
at all follow that we should see them.
It is good, as Keble says, "to have our thoughts lift up to that world
where all is beautiful and glorious,"--but it is well to realise also
how much of this world is beautiful. It has, I know, been maintained, as
for instance by Victor Hugo, that the general effect of beauty is to
sadden. "Comme la vie de l'homme, même la plus prospère, est toujours au
fond plus triste que gaie, le ciel sombre nous est harmonieux. Le ciel
éclatant et joyeux nous est ironique. La Nature triste nous ressemble et
nous console; la Nature rayonnante, magnifique, superbe ... a quelque
chose d'accablant."[1]
This seems to me, I confess, a morbid view. There are many no doubt on
whom the effect of natural beauty is to intensify feeling, to deepen
melancholy, as well as to raise the spirits. As Mrs. W. R. Greg in her
memoir of her husband tells us: "His passionate love for nature, so
amply fed by the beauty of the scenes around him, intensified the
emotions, as all keen perception of beauty does, but it did not add to
their joyousness. We speak of the pleasure which nature and art and
music give us; what we really mean is that our whole being is quickened
by the uplifting of the veil. Something passes into us which makes our
sorrows more sorrowful, our joys more joyful,--our whole life more
vivid. So it was with him. The long solitary wanderings over the hills,
and the beautiful moonlight nights on the lake served to make the
shadows seem darker that were brooding over his home."
But surely to most of us Nature when sombre, or even gloomy, is soothing
and consoling; when bright and beautiful, not only raises the spirits,
but inspires and elevates our whole being--
Nature never did betray
The heart that loved her; 'tis her privilege,
Through all the years of this our life, to lead
From joy to joy: for she can so inform
The mind that is within us, so impress
With quietness and beauty, and so feed
With lofty thoughts, that neither evil tongues,
Rash judgments, nor the sneers of selfish men,
Nor greetings where no kindness is, nor all
The dreary intercourse of daily life,
Shall e'er prevail against us, or disturb
Our cheerful faith, that all which we behold
Is full of blessings.[2]
Kingsley speaks with enthusiasm of the heaths and moors round his home,
"where I have so long enjoyed the wonders of nature; never, I can
honestly say, alone; because when man was not with me, I had companions
in every bee, and flower and pebble; and never idle, because I could not
pass a swamp, or a tuft of heather, without finding in it a fairy tale
of which I could but decipher here and there a line or two, and yet
found them more interesting than all the books, save one, which were
ever written upon earth."
Those who love Nature can never be dull. They may have other
temptations; but at least they will run no risk of being beguiled, by
ennui, idleness, or want of occupation, "to buy the merry madness of an
hour with the long penitence of after time." The love of Nature, again,
helps us greatly to keep ourselves free from those mean and petty cares
which interfere so much with calm and peace of mind. It turns "every
ordinary walk into a morning or evening sacrifice," and brightens life
until it becomes almost like a fairy tale.
In the romances of the Middle Ages we read of knights who loved, and
were loved by, Nature spirits,--of Sir Launfal and the Fairy Tryamour,
who furnished him with many good things, including a magic purse, in
which
As oft as thou puttest thy hand therein
A mark of gold thou shalt iwinne,
as well as protection from the main dangers of life. Such times have
passed away, but better ones have come. It is not now merely the few,
who are so favoured. All those who love Nature she loves in return, and
will richly reward, not perhaps with the good things, as they are
commonly called, but with the best things, of this world; not with money
and titles, horses and carriages, but with bright and happy thoughts,
contentment and peace of mind.
Happy indeed is the naturalist: to him the seasons come round like old
friends; to him the birds sing: as he walks along, the flowers stretch
out from the hedges, or look up from the ground, and as each year fades
away, he looks back on a fresh store of happy memories.
Though we can never "remount the river of our years," he who loves
Nature is always young. But what is the love of Nature? Some seem to
think they show a love of flowers by gathering them. How often one finds
a bunch of withered blossoms on the roadside, plucked only to be thrown
away! Is this love of Nature? It is, on the contrary, a wicked waste,
for a waste of beauty is almost the worst waste of all.
If we could imagine a day prolonged for a lifetime, or nearly so, and
that sunrise and sunset were rare events which happened but a few times
to each of us, we should certainly be entranced by the beauty of the
morning and evening tints. The golden rays of the morning are a fortune
in themselves, but we too often overlook the loveliness of Nature,
because it is constantly before us. For "the senseless folk," says King
Alfred,
is far more struck
At things it seldom sees.
"Well," says Cicero, "did Aristotle observe, 'If there were men whose
habitations had been always underground, in great and commodious houses,
adorned with statues and pictures, furnished with everything which they
who are reputed happy abound with; and if, without stirring from thence,
they should be informed of a certain divine power and majesty, and,
after some time, the earth should open, and they should quit their dark
abode to come to us; where they should immediately behold the earth, the
seas, the heavens; should consider the vast extent of the clouds and
force of the winds; should see the sun, and observe his grandeur and
beauty, and also his creative power, inasmuch as day is occasioned by
the diffusion of his light through the sky; and when night has obscured
the earth, they should contemplate the heavens bespangled and adorned
with stars; the surprising variety of the moon, in her increase and
wane; the rising and setting of all the stars, and the inviolable
regularity of their courses; when,' says he, 'they should see these
things, they would undoubtedly conclude that there are Gods, and that
these are their mighty works.'"[3]
Is my life vulgar, my fate mean,
Which on such golden memories can lean?[4]
At the same time the change which has taken place in the character of
our religion has in one respect weakened the hold which Nature has upon
our feelings. To the Greeks--to our own ancestors,--every River or
Mountain or Forest had not only its own special Deity, but in some sense
was itself instinct with life. They were not only peopled by Nymphs and
Fauns, Elves and Kelpies, were not only the favourite abodes of Water,
Forest, or Mountain Spirits, but they had a conscious existence of their
own.
In the Middle Ages indeed, these spirits were regarded as often
mischievous, and apt to take offence; sometimes as essentially
malevolent--even the most beautiful, like the Venus of Tannhäuser, being
often on that very account all the more dangerous; while the Mountains
and Forests, the Lakes and Seas, were the abodes of hideous ghosts and
horrible monsters, of Giants and Ogres, Sorcerers and Demons. These
fears, though vague, were none the less extreme, and the judicial
records of the Middle Ages furnish only too conclusive evidence that
they were a terrible reality. The light of Science has now happily
dispelled these fearful nightmares.
Unfortunately, however, as men have multiplied, their energies have
hitherto tended, not to beautify, but to mar. Forests have been cut
down, and replaced by flat fields in geometrical squares, or on the
continent by narrow strips. Here and there indeed we meet with oases, in
which beauty has not been sacrificed to profit, and it is then happily
found that not only is there no loss, but the earth seems to reward even
more richly those who treat her with love and respect.
Scarcely any part of the world affords so great a variety in so small an
area as our own island. Commencing in the south, we have first the blue
sea itself, the pebbly beaches, the white chalk cliffs of Kent, the
tinted sands of Alum Bay, the Red Sandstone of Devonshire, Granite and
Gneiss in Cornwall: inland we have the chalk Downs and clear streams,
the well-wooded weald and the rich hop gardens; farther westwards the
undulating gravelly hills, and still farther the granite tors: in the
centre of England we have to the east the Norfolk Broads and the Fens;
then the fertile Midlands, the cornfields, rich meadows, and large oxen;
and to the west the Welsh mountains; farther north the Yorkshire Wolds,
the Lancashire hills, the Lakes of Westmoreland; lastly, the swelling
hills, bleak moors, and picturesque castles of Northumberland and
Cumberland.
There are of course far larger rivers, but perhaps none lovelier than
The crystal Thamis wont to glide
In silver channel, down along the lee,[5]
[Illustration: WINDSOR CASTLE.
_To face page 13._]
by lawns and parks, meadows and wooded banks, dotted with country houses
and crowned by Windsor Castle itself (see Frontispiece). By many
Scotland is considered even more beautiful.
And yet too many of us see nothing in the fields but sacks of wheat, in
the meadows but trusses of hay, and in woods but planks for houses, or
cover for game. Even from this more prosaic point of view, how much
there is to wonder at and admire, in the wonderful chemistry which
changes grass and leaves, flowers and seeds, into bread and milk, eggs
and cream, butter and honey!
Almost everything, says Hamerton, "that the Peasant does, is lifted
above vulgarity by ancient, and often sacred, associations." There is,
indeed, hardly any business or occupation with reference to which the
same might not be said. The triviality or vulgarity does not depend on
what we do, but on the spirit in which it is done. Not only the regular
professions, but every useful occupation in life, however humble, is
honourable in itself, and may be pursued with dignity and peace.
Working in this spirit we have also the satisfaction of feeling that, as
in some mountain track every one who takes the right path, seems to make
the way clearer for those who follow; so may we also raise the
profession we adopt, and smooth the way for those who come after us.
But, even for those who are not Agriculturists, it must be admitted that
the country has special charms. One perhaps is the continual change.
Every week brings some fresh leaf or flower, bird or insect. Every month
again has its own charms and beauty. We sit quietly at home and Nature
decks herself for us.
In truth we all love change. Some think they do not care for it, but I
doubt if they know themselves.
"Not," said Jefferies, "for many years was I able to see why I went the
same round and did not care for change. I do not want change: I want the
same old and loved things, the same wild flowers, the same trees and
soft ash-green; the turtle-doves, the blackbirds, the coloured
yellow-hammer sing, sing, singing so long as there is light to cast a
shadow on the dial, for such is the measure of his song, and I want
them in the same place. Let me find them morning after morning, the
starry-white petals radiating, striving upwards up to their ideal. Let
me see the idle shadows resting on the white dust; let me hear the
humble-bees, and stay to look down on the yellow dandelion disk. Let me
see the very thistles opening their great crowns--I should miss the
thistles; the reed grasses hiding the moor-hen; the bryony bine, at
first crudely ambitious and lifted by force of youthful sap straight
above the hedgerow to sink of its weight presently and progress with
crafty tendrils; swifts shot through the air with outstretched wings
like crescent-headed shaftless arrows darted from the clouds; the
chaffinch with a feather in her bill; all the living staircase of the
spring, step by step, upwards to the great gallery of the summer, let me
watch the same succession year by year."
After all then he did enjoy the change and the succession.
Kingsley again in his charming prose idyll "My Winter Garden" tries to
persuade himself that he was glad he had never travelled, "having never
yet actually got to Paris." Monotony, he says, "is pleasant in itself;
morally pleasant, and morally useful. Marriage is monotonous; but there
is much, I trust, to be said in favour of holy wedlock. Living in the
same house is monotonous; but three removes, say the wise, are as bad as
a fire. Locomotion is regarded as an evil by our Litany. The Litany, as
usual, is right. 'Those who travel by land or sea' are to be objects of
our pity and our prayers; and I do pity them. I delight in that same
monotony. It saves curiosity, anxiety, excitement, disappointment, and a
host of bad passions."
But even as he writes one can see that he does not convince himself.
Possibly, he admits, "after all, the grapes are sour"; and when some
years after he did travel, how happy he was! At last, he says,
triumphantly, "At last we too are crossing the Atlantic. At last the
dream of forty years, please God, would be fulfilled, and I should see
(and happily not alone), the West Indies and the Spanish Main. From
childhood I had studied their Natural History, their Charts, their
Romances; and now, at last, I was about to compare books with facts, and
judge for myself of the reported wonders of the Earthly Paradise."
No doubt there is much to see everywhere. The Poet and the Naturalist
find "tropical forests in every square foot of turf." It may even be
better, and especially for the more sensitive natures, to live mostly in
quiet scenery, among fields and hedgerows, woods and downs; but it is
surely good for every one, from time to time, to refresh and strengthen
both mind and body by a spell of Sea air or Mountain beauty.
On the other hand we are told, and told of course with truth, that
though mountains may be the cathedrals of Nature, they are generally
remote from centres of population; that our great cities are grimy,
dark, and ugly; that factories are creeping over several of our
counties, blighting them into building ground, replacing trees by
chimneys, and destroying almost every vestige of natural beauty.
But if this be true, is it not all the more desirable that our people
should have access to pictures and books, which may in some small
degree, at any rate, replace what they have thus unfortunately lost? We
cannot all travel; and even those who can, are able to see but a small
part of the world. Moreover, though no one who has once seen, can ever
forget, the Alps, the Swiss lakes, or the Riviera, still the
recollection becomes less vivid as years roll on, and it is pleasant,
from time to time, to be reminded of their beauties.
There is one other advantage not less important. We sometimes speak as
if to visit a country, and to see it, were the same thing. But this is
not so. It is not every one who can see Switzerland like a Ruskin or a
Tyndall. Their beautiful descriptions of mountain scenery depend less on
their mastery of the English language, great as that is, than on their
power of seeing what is before them. It has been to me therefore a
matter of much interest to know which aspects of Nature have given the
greatest pleasure to, or have most impressed, those who, either from
wide experience or from their love of Nature, may be considered best
able to judge. I will begin with an English scene from Kingsley. He is
describing his return from a day's trout-fishing:--
"What shall we see," he says, "as we look across the broad, still, clear
river, where the great dark trout sail to and fro lazily in the sun?
White chalk fields above, quivering hazy in the heat. A park full of
merry hay-makers; gay red and blue waggons; stalwart horses switching
off the flies; dark avenues of tall elms; groups of abele, 'tossing
their whispering silver to the sun'; and amid them the house,--a great
square red-brick mass, made light and cheerful though by quoins and
windows of white Sarsden stone, with high peaked French roofs, broken by
louvres and dormers, haunted by a thousand swallows and starlings. Old
walled gardens, gay with flowers, shall stretch right and left. Clipt
yew alleys shall wander away into mysterious glooms, and out of their
black arches shall come tripping children, like white fairies, to laugh
and talk with the girl who lies dreaming and reading in the hammock
there, beneath the black velvet canopy of the great cedar tree, like
some fair tropic flower hanging from its boughs; and we will sit down,
and eat and drink among the burdock leaves, and then watch the quiet
house, and lawn, and flowers, and fair human creatures, and shining
water, all sleeping breathless in the glorious light beneath the
glorious blue, till we doze off, lulled by the murmur of a thousand
insects, and the rich minstrelsy of nightingale and blackcap, thrush and
dove.
"Peaceful, graceful, complete English country life and country houses;
everywhere finish and polish; Nature perfected by the wealth and art of
peaceful centuries! Why should I exchange you, even for the sight of all
the Alps?"
Though Jefferies was unfortunately never able to travel, few men have
loved Nature more devotedly, and speaking of his own home he expresses
his opinion that: "Of all sweet things there is none so sweet as fresh
air--one great flower it is, drawn round about; over, and enclosing us,
like Aphrodite's arms; as if the dome of the sky were a bell-flower
drooping down over us, and the magical essence of it filling all the
room of the earth. Sweetest of all things is wild-flower air. Full of
their ideal the starry flowers strained upwards on the bank, striving to
keep above the rude grasses that push by them; genius has ever had such
a struggle. The plain road was made beautiful by the many thoughts it
gave. I came every morning to stay by the star-lit bank."
Passing to countries across the ocean, Humboldt tells us that: "If I
might be allowed to abandon myself to the recollection of my own distant
travels, I would instance, amongst the most striking scenes of nature,
the calm sublimity of a tropical night, when the stars, not sparkling,
as in our northern skies, shed their soft and planetary light over the
gently heaving ocean; or I would recall the deep valleys of the
Cordilleras, where the tall and slender palms pierce the leafy veil
around them, and waving on high their feathery and arrow-like branches,
form, as it were, 'a forest above a forest'; or I would describe the
summit of the Peak of Teneriffe, when a horizon layer of clouds,
dazzling in whiteness, has separated the cone of cinders from the plain
below, and suddenly the ascending current pierces the cloudy veil, so
that the eye of the traveller may range from the brink of the crater,
along the vine-clad slopes of Orotava, to the orange gardens and banana
groves that skirt the shore. In scenes like these, it is not the
peaceful charm uniformly spread over the face of nature that moves the
heart, but rather the peculiar physiognomy and conformation of the land,
the features of the landscape, the ever-varying outline of the clouds,
and their blending with the horizon of the sea, whether it lies spread
before us like a smooth and shining mirror, or is dimly seen through the
morning mist. All that the senses can but imperfectly comprehend, all
that is most awful in such romantic scenes of nature, may become a
source of enjoyment to man, by opening a wide field to the creative
power of his imagination. Impressions change with the varying movements
of the mind, and we are led by a happy illusion to believe that we
receive from the external world that with which we have ourselves
invested it."
Humboldt also singles out for especial praise the following description
given of Tahiti by Darwin[6]:--
"The land capable of cultivation is scarcely in any part more than a
fringe of low alluvial soil, accumulated round the base of mountains,
and protected from the waves of the sea by a coral reef, which encircles
at a distance the entire line of coast. The reef is broken in several
parts so that ships can pass through, and the lake of smooth water
within, thus affords a safe harbour, as well as a channel for the native
canoes. The low land which comes down to the beach of coral sand is
covered by the most beautiful productions of the inter-tropical regions.
In the midst of bananas, orange, cocoa-nut, and breadfruit trees, spots
are cleared where yams, sweet potatoes, sugar-cane, and pine-apples are
cultivated. Even the brushwood is a fruit tree, namely, the guava,
which from its abundance is as noxious as a weed. In Brazil I have often
admired the contrast of varied beauty in the banana, palm, and orange
tree; here we have in addition the breadfruit tree, conspicuous from its
large, glossy, and deeply digitated leaf. It is admirable to behold
groves of a tree, sending forth its branches with the force of an
English Oak, loaded with large and most nutritious fruit. However little
on most occasions utility explains the delight received from any fine
prospect, in this case it cannot fail to enter as an element in the
feeling. The little winding paths, cool from the surrounding shade, led
to the scattered houses; and the owners of these everywhere gave us a
cheerful and most hospitable reception."
Darwin himself has told us, after going round the world that "in calling
up images of the past, I find the plains of Patagonia frequently cross
before my eyes; yet these plains are pronounced by all to be most
wretched and useless. They are characterised only by negative
possessions; without habitations, without water, without trees, without
mountains, they support only a few dwarf plants. Why then--and the case
is not peculiar to myself--have these arid wastes taken so firm
possession of my mind? Why have not the still more level, the greener
and more fertile pampas, which are serviceable to mankind, produced an
equal impression? I can scarcely analyse these feelings, but it must be
partly owing to the free scope given to the imagination. The plains of
Patagonia are boundless, for they are scarcely practicable, and hence
unknown; they bear the stamp of having thus lasted for ages, and there
appears no limit to their duration through future time. If, as the
ancients supposed, the flat earth was surrounded by an impassable
breadth of water, or by deserts heated to an intolerable excess, who
would not look at these last boundaries to man's knowledge with deep but
ill-defined sensations?"
Hamerton, whose wide experience and artistic power make his opinion
especially important, says:--
"I know nothing in the visible world that combines splendour and purity
so perfectly as a great mountain entirely covered with frozen snow and
reflected in the vast mirror of a lake. As the sun declines, its
thousand shadows lengthen, pure as the cold green azure in the depth of
a glacier's crevasse, and the illuminated snow takes first the tender
colour of a white rose, and then the flush of a red one, and the sky
turns to a pale malachite green, till the rare strange vision fades into
ghastly gray, but leaves with you a permanent recollection of its too
transient beauty."[7]
Wallace especially, and very justly, praises the description of tropical
forest scenery given by Belt in his charming _Naturalist in
Nicaragua_:--
"On each side of the road great trees towered up, carrying their crowns
out of sight amongst a canopy of foliage, and with lianas hanging from
nearly every bough, and passing from tree to tree, entangling the giants
in a great network of coiling cables. Sometimes a tree appears covered
with beautiful flowers which do not belong to it, but to one of the
lianas that twines through its branches and sends down great rope-like
stems to the ground. Climbing ferns and vanilla cling to the trunks, and
a thousand epiphytes perch themselves on the branches. Amongst these are
large arums that send down long aerial roots, tough and strong, and
universally used instead of cordage by the natives. Amongst the
undergrowth several small species of palms, varying in height from two
to fifteen feet, are common; and now and then magnificent tree ferns
send off their feathery crowns twenty feet from the ground to delight
the sight by their graceful elegance. Great broad-leaved heliconias,
leathery melastomæ, and succulent-stemmed, lop-sided leaved and
flesh-coloured begonias are abundant, and typical of tropical American
forests; but not less so are the cecropia trees, with their white stems
and large palmated leaves standing up like great candelabra. Sometimes
the ground is carpeted with large flowers, yellow, pink, or white, that
have fallen from some invisible tree-top above; or the air is filled
with a delicious perfume, the source of which one seeks around in vain,
for the flowers that cause it are far overhead out of sight, lost in the
great over-shadowing crown of verdure."
"But," he adds, "the uniformity of climate which has led to this rich
luxuriance and endless variety of vegetation is also the cause of a
monotony that in time becomes oppressive." To quote the words of Mr.
Belt: "Unknown are the autumn tints, the bright browns and yellows of
English woods; much less the crimsons, purples, and yellows of Canada,
where the dying foliage rivals, nay, excels, the expiring dolphin in
splendour. Unknown the cold sleep of winter; unknown the lovely
awakening of vegetation at the first gentle touch of spring. A ceaseless
round of ever-active life weaves the fairest scenery of the tropics into
one monotonous whole, of which the component parts exhibit in detail
untold variety of beauty."
Siberia is no doubt as a rule somewhat severe and inhospitable, but M.
Patrin mentions with enthusiasm how one day descending from the frozen
summits of the Altai, he came suddenly on a view of the plain of the
Obi--the most beautiful spectacle, he says, which he had ever witnessed.
Behind him were barren rocks and the snows of winter, in front a great
plain, not indeed entirely green, or green only in places, and for the
rest covered by three flowers, the purple Siberian Iris, the golden
Hemerocallis, and the silvery Narcissus--green, purple, gold, and white,
as far as the eye could reach.
Wallace tells us that he himself has derived the keenest enjoyment from
his sense of colour:--
"The heavenly blue of the firmament, the glowing tints of sunset, the
exquisite purity of the snowy mountains, and the endless shades of green
presented by the verdure-clad surface of the earth, are a never-failing
source of pleasure to all who enjoy the inestimable gift of sight. Yet
these constitute, as it were, but the frame and background of a
marvellous and ever-changing picture. In contrast with these broad and
soothing tints, we have presented to us in the vegetable and animal
worlds an infinite variety of objects adorned with the most beautiful
and most varied hues. Flowers, insects, and birds are the organisms
most generally ornamented in this way; and their symmetry of form, their
variety of structure, and the lavish abundance with which they clothe
and enliven the earth, cause them to be objects of universal admiration.
The relation of this wealth of colour to our mental and moral nature is
indisputable. The child and the savage alike admire the gay tints of
flowers, birds, and insects; while to many of us their contemplation
brings a solace and enjoyment which is both intellectually and morally
beneficial. It can then hardly excite surprise that this relation was
long thought to afford a sufficient explanation of the phenomena of
colour in nature; and although the fact that--
Full many a flower is born to blush unseen,
And waste its sweetness on the desert air,
might seem to throw some doubt on the sufficiency of the explanation,
the answer was easy,--that in the progress of discovery man would,
sooner or later, find out and enjoy every beauty that the hidden
recesses of the earth have in store for him."
Professor Colvin speaks with special admiration of Greek scenery:--
"In other climates, it is only in particular states of the weather that
the remote ever seems so close, and then with an effect which is sharp
and hard as well as clear; here the clearness is soft; nothing cuts or
glitters, seen through that magic distance; the air has not only a new
transparency so that you can see farther into it than elsewhere, but a
new quality, like some crystal of an unknown water, so that to see into
it is greater glory." Speaking of the ranges and promontories of sterile
limestone, the same writer observes that their colours are as austere
and delicate as the forms. "If here the scar of some old quarry throws a
stain, or there the clinging of some thin leafage spreads a bloom, the
stain is of precious gold, and the bloom of silver. Between the blue of
the sky and the tenfold blue of the sea these bare ranges seem, beneath
that daylight, to present a whole system of noble colour flung abroad
over perfect forms. And wherever, in the general sterility, you find a
little moderate verdure--a little moist grass, a cluster of
cypresses--or whenever your eye lights upon the one wood of the
district, the long olive grove of the Cephissus, you are struck with a
sudden sense of richness, and feel as if the splendours of the tropics
would be nothing to this."
Most travellers have been fascinated by the beauty of night in the
tropics. Our evenings no doubt are often delicious also, though the mild
climate we enjoy is partly due to the sky being so often overcast. In
parts of the tropics, however, the air is calm and cloudless throughout
nearly the whole of the year. There is no dew, and the inhabitants sleep
on the house-tops, in full view of the brightness of the stars and the
beauty of the sky, which is almost indescribable.
"Il faisait," says Bernardin de St. Pierre of such a scene, "une de ces
nuits délicieuses, si communes entre les tropiques, et dont le plus
abile pinceau ne rendrait pas le beauté. La lune paraissait au milieu du
firmament, entourée d'un rideau de nuages, que ses rayons dissipaient
par degrés. Sa lumière se répandait insensiblement sur les montagnes de
l'île et sur leurs pitons, qui brillaient d'un vert argenté. Les vents
retenaient leurs haleines. On entendait dans les bois, au fond des
vallées, au haut des rochers, de petits cris, de doux murmures
d'oiseaux, qui se caressaient dans leurs nids, réjouis par la clarté de
la nuit et la tranquillité de l'air. Tous, jusqu'aux insectes,
bruissaient sous l'herbe. Les étoiles étincelaient au ciel, et se
réfléchissaient au sein de la mer, qui répétait leurs images
tremblantes."
In the Arctic and Antarctic regions the nights are often made quite
gorgeous by the Northern Lights or Aurora borealis, and the
corresponding appearance in the Southern hemisphere. The Aurora borealis
generally begins towards evening, and first appears as a faint glimmer
in the north, like the approach of dawn. Gradually a curve of light
spreads like an immense arch of yellowish-white hue, which gains rapidly
in brilliancy, flashes and vibrates like a flame in the wind. Often two
or even three arches appear one over the other. After a while coloured
rays dart upwards in divergent pencils, often green below, yellow in the
centre, and crimson above, while it is said that sometimes almost
black, or at least very dark violet, rays are interspersed among the
rings of light, and heighten their effect by contrast. Sometimes the two
ends of the arch seem to rise off the horizon, and the whole sheet of
light throbs and undulates like a fringed curtain of light; sometimes
the sheaves of rays unite into an immense cupola; while at others the
separate rays seem alternately lit and extinguished. Gradually the light
flickers and fades away, and has generally disappeared before the first
glimpse of dawn.
We seldom see the Aurora in the south of England, but we must not
complain; our winters are mild, and every month has its own charm and
beauty.
In January we have the lengthening days.
" February " the first butterfly.
" March " the opening buds.
" April " the young leaves and spring flowers.
" May " the song of birds.
" June " the sweet new-mown hay.
" July " the summer flowers.
" August " the golden grain.
" September " the fruit.
" October " the autumn tints.
" November " the hoar frost on trees and the pure snow.
" December " last not least, the holidays of Christmas, and the
bright fireside.
It is well to begin the year in January, for we have then before us all
the hope of spring.
Oh wind,
If winter comes, can spring be long behind?[8]
Spring seems to revive us all. In the Song of Solomon--
My beloved spake, and said unto me,
Rise up, my love, my fair one, and come away.
For, lo, the winter is past,
The rain is over and gone;
The flowers appear on the earth;
The time of the singing of birds is come,
The voice of the turtle is heard in our land,
The fig tree putteth forth her green figs,
And the vines with the tender grape give a good smell.
"But indeed there are days," says Emerson, "which occur in this climate,
at almost any season of the year, wherein the world reaches its
perfection, when the air, the heavenly bodies, and the earth make a
harmony, as if nature would indulge her offspring.... These halcyon days
may be looked for with a little more assurance in that pure October
weather, which we distinguish by the name of the Indian summer. The day,
immeasurably long, sleeps over the broad hills and warm wide fields. To
have lived through all its sunny hours, seems longevity enough." Yet
does not the very name of Indian summer imply the superiority of the
summer itself,--the real, the true summer, "when the young corn is
bursting into ear; the awned heads of rye, wheat, and barley, and the
nodding panicles of oats, shoot from their green and glaucous stems, in
broad, level, and waving expanses of present beauty and future promise.
The very waters are strewn with flowers: the buck-bean, the
water-violet, the elegant flowering rush, and the queen of the waters,
the pure and splendid white lily, invest every stream and lonely mere
with grace."[9]
For our greater power of perceiving, and therefore of enjoying Nature,
we are greatly indebted to Science. Over and above what is visible to
the unaided eye, the two magic tubes, the telescope and microscope, have
revealed to us, at least partially, the infinitely great and the
infinitely little.
Science, our Fairy Godmother, will, unless we perversely reject her
help, and refuse her gifts, so richly endow us, that fewer hours of
labour will serve to supply us with the material necessaries of life,
leaving us more time to ourselves, more leisure to enjoy all that makes
life best worth living.
Even now we all have some leisure, and for it we cannot be too grateful.
"If any one," says Seneca, "gave you a few acres, you would say that you
had received a benefit; can you deny that the boundless extent of the
earth is a benefit? If a house were given you, bright with marble, its
roof beautifully painted with colours and gilding, you would call it no
small benefit. God has built for you a mansion that fears no fire or
ruin ... covered with a roof which glitters in one fashion by day, and
in another by night. Whence comes the breath which you draw; the light
by which you perform the actions of your life? the blood by which your
life is maintained? the meat by which your hunger is appeased?... The
true God has planted, not a few oxen, but all the herds on their
pastures throughout the world, and furnished food to all the flocks; he
has ordained the alternation of summer and winter ... he has invented so
many arts and varieties of voice, so many notes to make music.... We
have implanted in us the seeds of all ages, of all arts; and God our
Master brings forth our intellects from obscurity."[10]
FOOTNOTES:
[1] _Choses Vues._
[2] Wordsworth.
[3] Cicero, _De Natura Deorum_.
[4] Thoreau.
[5] Spenser.
[6] Darwin's _Voyage of the Beagle_.
[7] Hamerton's _Landscape_.
[8] Shelley.
[9] Howitt's _Book of the Seasons_.
[10] Seneca, _De Beneficiis_.
CHAPTER II
ON ANIMAL LIFE
If thy heart be right, then will every creature be to thee a
mirror of life, and a book of holy doctrine.
THOMAS À KEMPIS.
CHAPTER II
ON ANIMAL LIFE
There is no species of animal or plant which would not well repay, I
will not say merely the study of a day, but even the devotion of a
lifetime. Their form and structure, development and habits, geographical
distribution, relation to other living beings, and past history,
constitute an inexhaustible study.
When we consider how much we owe to the Dog, Man's faithful friend, to
the noble Horse, the patient Ox, the Cow, the Sheep, and our other
domestic animals, we cannot be too grateful to them; and if we cannot,
like some ancient nations, actually worship them, we have perhaps fallen
into the other extreme, underrate the sacredness of animal life, and
treat them too much like mere machines.
Some species, however, are no doubt more interesting than others,
especially perhaps those which live together in true communities, and
which offer so many traits--some sad, some comical, and all
interesting,--which reproduce more or less closely the circumstances of
our own life.
The modes of animal life are almost infinitely diversified; some live on
land, some in water; of those which are aquatic some dwell in rivers,
some in lakes or pools, some on the sea-shore, others in the depths of
the ocean. Some burrow in the ground, some find their home in the air.
Some live in the Arctic regions, some in the burning deserts; one little
beetle (Hydrobius) in the thermal waters of Hammam-Meskoutin, at a
temperature of 130°. As to food, some are carnivorous and wage open war;
some, more insidious, attack their victims from within; others feed on
vegetable food, on leaves or wood, on seeds or fruits; in fact, there is
scarcely an animal or vegetable substance which is not the special and
favourite food of one or more species. Hence to adapt them to these
various requirements we find the utmost differences of form and size
and structure. Even the same individual often goes through great
changes.
GROWTH AND METAMORPHOSES
The development, indeed, of an animal from birth to maturity is no mere
question of growth. The metamorphoses of Insects have long excited the
wonder and admiration of all lovers of nature. They depend to a great
extent on the fact that the little creatures quit the egg at an early
stage of development, and lead a different life, so that the external
forces acting on them, are very different from those by which they are
affected when they arrive at maturity. A remarkable case is that of
certain Beetles which are parasitic on Solitary Bees. The young larva is
very active, with six strong legs. It conceals itself in some flower,
and when the Bee comes in search of honey, leaps upon her, but is so
minute as not to be perceived. The Bee constructs her cell, stores it
with honey, and lays her egg. At that moment the little larva quits the
Bee and jumps on to the egg, which she proceeds gradually to devour.
Having finished the egg, she attacks the honey; but under these
circumstances the activity which was at first so necessary has become
useless; the legs which did such good service are no longer required;
and the active slim larva changes into a white fleshy grub, which floats
comfortably in the honey with its mouth just below the surface.
Even in the same group we may find great differences. For instance, in
the family of Insects to which Bees and Wasps belong, some have grub
larvæ, such as the Bee and Ant; some have larvæ like caterpillars, such
as the Sawflies; and there is a group of minute forms the larvæ of which
live inside the eggs of other insects, and present very remarkable and
abnormal forms.
These differences depend mainly on the mode of life and the character of
the food.
RUDIMENTARY ORGANS
Such modifications may be called adaptive, but there are others of a
different origin that have reference to the changes which the race has
passed through in bygone ages. In fact the great majority of animals do
go through metamorphoses (many of them as remarkable, though not so
familiar as those of insects), but in many cases they are passed through
within the egg and thus escape popular observation. Naturalists who
accept the theory of evolution, consider that the development of each
individual represents to a certain extent that which the species has
itself gone through in the lapse of ages; that every individual contains
within itself, so to say, a history of the race. Thus the rudimentary
teeth of Cows, Sheep, Whales, etc. (which never emerge from their
sockets), the rudimentary toes of many mammals, the hind legs of Whales
and of the Boa-constrictor, which are imbedded in the flesh, the
rudimentary collar-bone of the Dog, etc., are indications of descent
from ancestors in which these organs were fully developed. Again, though
used for such different purposes, the paddle of a Whale, the leg of a
Horse and of a Mole, the wing of a Bird or a Bat, and the arm of a Man,
are all constructed on the same model, include corresponding bones, and
are similarly arranged. The long neck of the Giraffe, and the short one
of the Whale (if neck it can be called), contain the same number of
vertebræ.
Even after birth the young of allied species resemble one another much
more than the mature forms. The stripes on the young Lion, the spots on
the young Blackbird, are well-known cases; and we find the same law
prevalent among the lower animals, as, for instance, among Insects and
Crustacea. The Lobster, Crab, Shrimp, and Barnacle are very unlike when
full grown, but in their young stages go through essentially similar
metamorphoses.
No animal is perhaps in this respect more interesting than the Horse.
The skull of a Horse and that of a Man, though differing so much, are,
says Flower,[11] "composed of exactly the same number of bones, having
the same general arrangement and relation to each other. Not only the
individual bones, but every ridge and surface for the attachment of
muscles, and every hole for the passage of artery or nerve, seen in the
one can be traced in the other." It is often said that the Horse
presents a remarkable peculiarity in that the canine teeth grow but
once. There are, however, in most Horses certain spicules or minute
points which are shed before the appearance of the permanent canines,
and which are probably the last remnants of the true milk canines.
The foot is reduced to a single toe, representing the third digit, but
the second and fourth, though rudimentary, are represented by the splint
bones; while the foot also contains traces of several muscles,
originally belonging to the toes which have now disappeared, and which
"linger as it were behind, with new relations and uses, sometimes in a
reduced, and almost, if not quite, functionless condition." Even Man
himself presents traces of gill-openings, and indications of other
organs which are fully developed in lower animals.
MODIFICATIONS
There is in New Zealand a form of Crow (Hura), in which the female has
undergone a very curious modification. It is the only case I know, in
which the bill is differently shaped in the two sexes. The bird has
taken on the habits of a Woodpecker, and the stout crow-like bill of the
cock-bird is admirably adapted to tap trees, and if they sound hollow,
to dig down to the burrow of the Insect; but it lacks the horny-pointed
tip of the tongue, which in the true Woodpecker is provided with
recurved hairs, thus enabling that bird to pierce the grub and draw it
out. In the Hura, however, the bill of the hen-bird has become much
elongated and slightly curved, and when the cock has dug down to the
burrow, the hen inserts her long bill and draws out the grub, which
they then divide between them: a very pretty illustration of the wife as
helpmate to the husband.
It was indeed until lately the general opinion that animals and plants
came into existence just as we now see them. We took pleasure in their
beauty; their adaptation to their habits and mode of life in many cases
could not be overlooked or misunderstood. Nevertheless the book of
Nature was like some missal richly illuminated, but written in an
unknown tongue. The graceful forms of the letters, the beauty of the
colouring, excited our wonder and admiration; but of the true meaning
little was known to us; indeed we scarcely realised that there was any
meaning to decipher. Now glimpses of the truth are gradually revealing
themselves, we perceive that there is a reason, and in many cases we
know what the reason is, for every difference in form, in size, and in
colour; for every bone and every feather, almost for every hair.[12]
COLOUR
The colours of animals, generally, I believe, serve as a protection. In
some, however, they probably render them more attractive to their mates,
of which the Peacock is one of the most remarkable illustrations.
In richness of colour birds and insects vie even with flowers. "One fine
red admiral butterfly," says Jefferies,[13] "whose broad wings,
stretched out like fans, looked simply splendid floating round and round
the willows which marked the margin of a dry pool. His blue markings
were really blue--blue velvet--his red and the white stroke shone as if
sunbeams were in his wings. I wish there were more of these butterflies;
in summer, dry summer, when the flowers seem gone and the grass is not
so dear to us, and the leaves are dull with heat, a little colour is so
pleasant. To me colour is a sort of food; every spot of colour is a drop
of wine to the spirit."
The varied colours which add so much to the beauty of animals and
plants are not only thus a delight to the eye, but afford us also some
of the most interesting problems in Natural History. Some probably are
not in themselves of any direct advantage. The brilliant mother-of-pearl
of certain shells, which during life is completely hidden, the rich
colours of some internal organs of animals, are not perhaps of any
direct benefit, but are incidental, like the rich and brilliant hues of
many minerals and precious stones.
But although this may be true, I believe that most of these colours are
now of some advantage. "The black back and silvery belly of fishes" have
been recently referred to by a distinguished naturalist as being
obviously of no direct benefit. I should on the contrary have quoted
this case as one where the advantage was obvious. The dark back renders
the fish less conspicuous to an eye looking down into the water; while
the white under-surface makes them less visible from below. The animals
of the desert are sand-coloured; those of the Arctic regions are white
like snow, especially in winter; and pelagic animals are blue.
Let us take certain special cases. The Lion, like other desert animals,
is sand-coloured; the Tiger which lives in the Jungle has vertical
stripes, making him difficult to see among the upright grass; Leopards
and the tree-cats are spotted, like rays of light seen through leaves.
An interesting case is that of the animals living in the Sargasso or
gulf-weed of the Atlantic. These creatures--Fish, Crustacea, and
Mollusks alike--are characterised by a peculiar colouring, not
continuously olive like the Seaweed itself, but blotched with rounded
more or less irregular patches of bright, opaque white, so as closely to
resemble fronds covered with patches of Flustra or Barnacles.
Take the case of caterpillars, which are especially defenceless, and
which as a rule feed on leaves. The smallest and youngest are green,
like the leaves on which they live. When they become larger, they are
characterised by longitudinal lines, which break up the surface and thus
render them less conspicuous. On older and larger ones the lines are
diagonal, like the nerves of leaves. Conspicuous caterpillars are
generally either nauseous in taste, or protected by hairs.
[Illustration: Fig. 1.--_Choerocampa porcellus._]
I say "generally," because there are some interesting exceptions. The
large caterpillars of some of the Elephant Hawkmoths are very
conspicuous, and rendered all the more so by the presence of a pair of
large eyelike spots. Every one who sees one of these caterpillars is
struck by its likeness to a snake, and the so-called "eyes" do much to
increase the deception. Moreover, the ring on which they are placed is
swollen, and the insect, when in danger, has the habit of retracting its
head and front segments, which gives it an additional resemblance to
some small reptile. That small birds are, as a matter of fact, afraid of
these caterpillars (which, however, I need not say, are in reality
altogether harmless) Weismann has proved by actual experiment. He put
one of these caterpillars in a tray, in which he was accustomed to place
seed for birds. Soon a little flock of sparrows and other small birds
assembled to feed as usual. One of them lit on the edge of this tray,
and was just going to hop in, when she spied the caterpillar.
Immediately she began bobbing her head up and down in the odd way which
some small birds have, but was afraid to go nearer. Another joined her
and then another, until at last there was a little company of ten or
twelve birds all looking on in astonishment, but not one ventured into
the tray; while one bird, which lit in it unsuspectingly, beat a hasty
retreat in evident alarm as soon as she perceived the caterpillar. After
waiting for some time, Weismann removed it, when the birds soon attacked
the seeds. Other caterpillars also are probably protected by their
curious resemblance to spotted snakes. One of the large Indian
caterpillars has even acquired the power of hissing.
Among perfect insects many resemble closely the substances near which
they live. Some moths are mottled so as to mimic the bark of trees, or
moss, or the surface of stones. One beautiful tropical butterfly has a
dark wing on which are painted a series of green leaf tips, so that it
closely resembles the edge of a pinnate leaf projecting out of shade
into sunshine.
The argument is strengthened by those cases in which the protection, or
other advantage, is due not merely to colour, but partly also to form.
Such are the insects which resemble sticks or leaves. Again, there are
cases in which insects mimic others, which, for some reason or other,
are less liable to danger. So also many harmless animals mimic others
which are poisonous or otherwise well protected. Some butterflies, as
Mr. Bates has pointed out, mimic others which are nauseous in taste, and
therefore not attacked by birds. In these cases it is generally only the
females that are mimetic, and in some cases only a part of them, so that
there are two, or even three, kinds of females, the one retaining the
normal colouring of the group, the other mimicking another species. Some
spiders closely resemble Ants, and several other insects mimic Wasps or
Hornets.
Some reptiles and fish have actually the power of changing the colour of
their skin so as to adapt themselves to their surroundings.
Many cases in which the colouring does not at first sight appear to be
protective, will on consideration be found to be so. It has, for
instance, been objected that sheep are not coloured green; but every
mountaineer knows that sheep could not have had a colour more adapted to
render them inconspicuous, and that it is almost impossible to
distinguish them from the rocks which so constantly crop up on hill
sides. Even the brilliant blue of the Kingfisher, which in a museum
renders it so conspicuous, in its native haunts, on the contrary, makes
it difficult to distinguish from a flash of light upon the water; and
the richly-coloured Woodpecker wears the genuine dress of a
Forester--the green coat and crimson cap.
It has been found that some brilliantly coloured and conspicuous animals
are either nauseous or poisonous. In these cases the brilliant colour
is doubtless a protection by rendering them more unmistakable.
COMMUNITIES
Some animals may delight us especially by their beauty, such as birds or
butterflies; others may surprise us by their size, as Elephants and
Whales, or the still more marvellous monsters of ancient times; may
fascinate us by their exquisite forms, such as many microscopic shells;
or compel our reluctant attention by their similarity to us in
structure; but none offer more points of interest than those which live
in communities. I do not allude to the temporary assemblages of
Starlings, Swallows, and other birds at certain times of year, nor even
to the permanent associations of animals brought together by common
wants in suitable localities, but to regular and more or less organised
associations. Such colonies as those of Rooks and Beavers have no doubt
interesting revelations and surprises in store for us, but they have not
been as yet so much studied as those of some insects. Among these the
Hive Bees, from the beauty and regularity of their cells, from their
utility to man, and from the debt we owe them for their unconscious
agency in the improvement of flowers, hold a very high place; but they
are probably less intelligent, and their relations with other animals
and with one another are less complex than in the case of Ants, which
have been so well studied by Gould, Huber, Forel, M'Cook, and other
naturalists.
The subject is a wide one, for there are at least a thousand species of
Ants, no two of which have the same habits. In this country we have
rather more than thirty, most of which I have kept in confinement. Their
life is comparatively long: I have had working Ants which were seven
years old, and a Queen Ant lived in one of my nests for fifteen years.
The community consists, in addition to the young, of males, which do no
work, of wingless workers, and one or more Queen mothers, who have at
first wings, which, however, after one Marriage flight, they throw off,
as they never leave the nest again, and in it wings would of course be
useless. The workers do not, except occasionally, lay eggs, but carry on
all the affairs of the community. Some of them, and especially the
younger ones, remain in the nest, excavate chambers and tunnels, and
tend the young, which are sorted up according to age, so that my nests
often had the appearance of a school, with the children arranged in
classes.
In our English Ants the workers in each species are all similar except
in size, but among foreign species there are some in which there are two
or even more classes of workers, differing greatly not only in size, but
also in form. The differences are not the result of age, nor of race,
but are adaptations to different functions, the nature of which,
however, is not yet well understood. Among the Termites those of one
class certainly seem to act as soldiers, and among the true Ants also
some have comparatively immense heads and powerful jaws. It is doubtful,
however, whether they form a real army. Bates observed that on a
foraging expedition the large-headed individuals did not walk in the
regular ranks, nor on the return did they carry any of the booty, but
marched along at the side, and at tolerably regular intervals, "like
subaltern officers in a marching regiment." He is disposed, however, to
ascribe to them a much humbler function, namely, to serve merely "as
indigestible morsels to the ant thrushes." This, I confess, seems to me
improbable.
Solomon was, so far as we yet know, quite correct in describing Ants as
having "neither guide, overseer, nor ruler." The so-called Queens are
really Mothers. Nevertheless it is true, and it is curious, that the
working Ants and Bees always turn their heads towards the Queen. It
seems as if the sight of her gave them pleasure. On one occasion, while
moving some Ants from one nest into another for exhibition at the Royal
Institution, I unfortunately crushed the Queen and killed her. The
others, however, did not desert her, or draw her out as they do dead
workers, but on the contrary carried her into the new nest, and
subsequently into a larger one with which I supplied them, congregating
round her for weeks just as if she had been alive. One could hardly
help fancying that they were mourning her loss, or hoping anxiously for
her recovery.
The Communities of Ants are sometimes very large, numbering even up to
500,000 individuals; and it is a lesson to us, that no one has ever yet
seen a quarrel between any two Ants belonging to the same community. On
the other hand it must be admitted that they are in hostility, not only
with most other insects, including Ants of different species, but even
with those of the same species if belonging to different communities. I
have over and over again introduced Ants from one of my nests into
another nest of the same species, and they were invariably attacked,
seized by a leg or an antenna, and dragged out.
It is evident therefore that the Ants of each community all recognise
one another, which is very remarkable. But more than this, I several
times divided a nest into two halves, and found that even after a
separation of a year and nine months they recognised one another, and
were perfectly friendly; while they at once attacked Ants from a
different nest, although of the same species.
It has been suggested that the Ants of each nest have some sign or
password by which they recognise one another. To test this I made some
insensible. First I tried chloroform, but this was fatal to them; and as
therefore they were practically dead, I did not consider the test
satisfactory. I decided therefore to intoxicate them. This was less easy
than I had expected. None of my Ants would voluntarily degrade
themselves by getting drunk. However, I got over the difficulty by
putting them into whisky for a few moments. I took fifty specimens,
twenty-five from one nest and twenty-five from another, made them dead
drunk, marked each with a spot of paint, and put them on a table close
to where other Ants from one of the nests were feeding. The table was
surrounded as usual with a moat of water to prevent them from straying.
The Ants which were feeding soon noticed those which I had made drunk.
They seemed quite astonished to find their comrades in such a
disgraceful condition, and as much at a loss to know what to do with
their drunkards as we are. After a while, however, to cut my story
short, they carried them all away: the strangers they took to the edge
of the moat and dropped into the water, while they bore their friends
home into the nest, where by degrees they slept off the effects of the
spirit. Thus it is evident that they know their friends even when
incapable of giving any sign or password.
This little experiment also shows that they help comrades in distress.
If a Wolf or a Rook be ill or injured, we are told that it is driven
away or even killed by its comrades. Not so with Ants. For instance, in
one of my nests an unfortunate Ant, in emerging from the chrysalis skin,
injured her legs so much that she lay on her back quite helpless. For
three months, however, she was carefully fed and tended by the other
Ants. In another case an Ant in the same manner had injured her antennæ.
I watched her also carefully to see what would happen. For some days she
did not leave the nest. At last one day she ventured outside, and after
a while met a stranger Ant of the same species, but belonging to another
nest, by whom she was at once attacked. I tried to separate them, but
whether by her enemy, or perhaps by my well-meant but clumsy kindness,
she was evidently much hurt and lay helplessly on her side. Several
other Ants passed her without taking any notice, but soon one came up,
examined her carefully with her antennæ, and carried her off tenderly to
the nest. No one, I think, who saw it could have denied to that Ant one
attribute of humanity, the quality of kindness.
The existence of such communities as those of Ants or Bees implies, no
doubt, some power of communication, but the amount is still a matter of
doubt. It is well known that if one Bee or Ant discovers a store of
food, others soon find their way to it. This, however, does not prove
much. It makes all the difference whether they are brought or sent. If
they merely accompany on her return a companion who has brought a store
of food, it does not imply much. To test this, therefore, I made
several experiments. For instance, one cold day my Ants were almost all
in their nests. One only was out hunting and about six feet from home. I
took a dead bluebottle fly, pinned it on to a piece of cork, and put it
down just in front of her. She at once tried to carry off the fly, but
to her surprise found it immovable. She tugged and tugged, first one way
and then another for about twenty minutes, and then went straight off to
the nest. During that time not a single Ant had come out; in fact she
was the only Ant of that nest out at the time. She went straight in, but
in a few seconds--less than half a minute,--came out again with no less
than twelve friends, who trooped off with her, and eventually tore up
the dead fly, carrying it off in triumph.
Now the first Ant took nothing home with her; she must therefore somehow
have made her friends understand that she had found some food, and
wanted them to come and help her to secure it. In all such cases,
however, so far as my experience goes, the Ants brought their friends,
and some of my experiments indicated that they are unable to send them.
Certain species of Ants, again, make slaves of others, as Huber first
observed. If a colony of the slave-making Ants is changing the nest, a
matter which is left to the discretion of the slaves, the latter carry
their mistresses to their new home. Again, if I uncovered one of my
nests of the Fuscous Ant (Formica fusca), they all began running about
in search of some place of refuge. If now I covered over one small part
of the nest, after a while some Ant discovered it. In such a case,
however, the brave little insect never remained there, she came out in
search of her friends, and the first one she met she took up in her
jaws, threw over her shoulder (their way of carrying friends), and took
into the covered part; then both came out again, found two more friends
and brought them in, the same manoeuvre being repeated until the whole
community was in a place of safety. This I think says much for their
public spirit, but seems to prove that, in F. fusca at least, the powers
of communication are but limited.
One kind of slave-making Ant has become so completely dependent on their
slaves, that even if provided with food they will die of hunger, unless
there is a slave to put it into their mouth. I found, however, that they
would thrive very well if supplied with a slave for an hour or so once a
week to clean and feed them.
But in many cases the community does not consist of Ants only. They have
domestic animals, and indeed it is not going too far to say that they
have domesticated more animals than we have. Of these the most important
are Aphides. Some species keep Aphides on trees and bushes, others
collect root-feeding Aphides into their nests. They serve as cows to the
Ants, which feed on the honey-dew secreted by the Aphides. Not only,
moreover, do the Ants protect the Aphides themselves, but collect their
eggs in autumn, and tend them carefully through the winter, ready for
the next spring. Many other insects are also domesticated by Ants, and
some of them, from living constantly underground, have completely lost
their eyes and become quite blind.
But I must not let myself be carried away by this fascinating subject,
which I have treated more at length in another work.[14] I will only say
that though their intelligence is no doubt limited, still I do not think
that any one who has studied the life-history of Ants can draw any
fundamental line of separation between instinct and reason.
When we see a community of Ants working together in perfect harmony, it
is impossible not to ask ourselves how far they are mere exquisite
automatons; how far they are conscious beings? When we watch an ant-hill
tenanted by thousands of industrious inhabitants, excavating chambers,
forming tunnels, making roads, guarding their home, gathering food,
feeding the young, tending their domestic animals--each one fulfilling
its duties industriously, and without confusion,--it is difficult
altogether to deny to them the gift of reason; and all our recent
observations tend to confirm the opinion that their mental powers differ
from those of men, not so much in kind as in degree.
FOOTNOTES:
[11] _The Horse._
[12] Lubbock, _Fifty Years of Science_.
[13] _The Open Air._
[14] _Ants, Bees, and Wasps._
CHAPTER III
ON ANIMAL LIFE--_continued_
An organic being is a microcosm--a little universe, formed of a
host of self-propagating organisms, inconceivably minute and
numerous as the stars of heaven.
DARWIN.
CHAPTER III
ON ANIMAL LIFE--_continued._
We constantly speak of animals as free. A fish, says Ruskin, "is much
freer than a Man; and as to a fly, it is a black incarnation of
freedom." It is pleasant to think of anything as free, but in this case
the idea is, I fear, to a great extent erroneous. Young animals may
frolic and play, but older ones take life very seriously. About the
habits of fish and flies, indeed, as yet we know very little. Any one,
however, who will watch animals will soon satisfy himself how diligently
they work. Even when they seem to be idling over flowers, or wandering
aimlessly about, they are in truth diligently seeking for food, or
collecting materials for nests. The industry of Bees is proverbial. When
collecting honey or pollen they often visit over twenty flowers in a
minute, keeping constantly to one species, without yielding a moment's
dalliance to any more sweet or lovely tempter. Ants fully deserve the
commendation of Solomon. Wasps have not the same reputation for
industry; but I have watched them from before four in the morning till
dark at night working like animated machines without a moment's rest or
intermission. Sundays and Bank Holidays are all the same to them. Again,
Birds have their own gardens and farms from which they do not wander,
and within which they will tolerate no interference. Their ideas of the
rights of property are far stricter than those of some statesmen. As to
freedom, they have their daily duties as much as a mechanic in a mill or
a clerk in an office. They suffer under alarms, moreover, from which we
are happily free. Mr. Galton believes that the life of wild animals is
very anxious. "From my own recollection," he says, "I believe that every
antelope in South Africa has to run for its life every one or two days
upon an average, and that he starts or gallops under the influence of a
false alarm many times in a day. Those who have crouched at night by the
side of pools in the desert, in order to have a shot at the beasts that
frequent it, see strange scenes of animal life; how the creatures gambol
at one moment and fight at another; how a herd suddenly halts in
strained attention, and then breaks into a maddened rush as one of them
becomes conscious of the stealthy movements or rank scent of a beast of
prey. Now this hourly life-and-death excitement is a keen delight to
most wild creatures, but must be peculiarly distracting to the
comfort-loving temperament of others. The latter are alone suited to
endure the crass habits and dull routine of domesticated life. Suppose
that an animal which has been captured and half-tamed, received
ill-usage from his captors, either as punishment or through mere
brutality, and that he rushed indignantly into the forest with his ribs
aching from blows and stones. If a comfort-loving animal, he will
probably be no gainer by the change, more serious alarms and no less
ill-usage awaits him: he hears the roar of the wild beasts, and the
headlong gallop of the frightened herds, and he finds the buttings and
the kicks of other animals harder to endure than the blows from which he
fled: he has peculiar disadvantages from being a stranger; the herds of
his own species which he seeks for companionship constitute so many
cliques, into which he can only find admission by more fighting with
their strongest members than he has spirit to undergo. As a set-off
against these miseries, the freedom of savage life has no charms for his
temperament; so the end of it is, that with a heavy heart he turns back
to the habitation he had quitted."
But though animals may not be free, I hope and believe that they are
happy. Dr. Hudson, an admirable observer, assures us with confidence
that the struggle for existence leaves them much leisure and famous
spirits. "In the animal world," he exclaims,[15] "what happiness reigns!
What ease, grace, beauty, leisure, and content! Watch these living
specks as they glide through their forests of algæ, all 'without hurry
and care,' as if their 'span-long lives' really could endure for the
thousand years that the old catch pines for. Here is no greedy jostling
at the banquet that nature has spread for them; no dread of each other;
but a leisurely inspection of the field, that shows neither the pressure
of hunger nor the dread of an enemy.
"'To labour and to be content' (that 'sweet life' of the son of
Sirach)--to be equally ready for an enemy or a friend--to trust in
themselves alone, to show a brave unconcern for the morrow, all these
are the admirable points of a character almost universal among animals,
and one that would lighten many a heart were it more common among men.
That character is the direct result of the golden law 'If one will not
work, neither let him eat'; a law whose stern kindness, unflinchingly
applied, has produced whole nations of living creatures, without a
pauper in their ranks, flushed with health, alert, resolute,
self-reliant, and singularly happy."
It has often been said that Man is the only animal gifted with the
power of enjoying a joke, but if animals do not laugh, at any rate they
sometimes play. We are, indeed, apt perhaps to credit them with too much
of our own attributes and emotions, but we can hardly be mistaken in
supposing that they enjoy certain scents and sounds. It is difficult to
separate the games of kittens and lambs from those of children. Our
countryman Gould long ago described the "amusements or sportive
exercises" which he had observed among Ants. Forel was at first
incredulous, but finally confirmed these statements; and, speaking of
certain tropical Ants, Bates says "the conclusion that they were engaged
in play was irresistible."
SLEEP
We share with other animals the great blessing of Sleep, nature's soft
nurse, "the mantle that covers thought, the food that appeases hunger,
the drink that quenches thirst, the fire that warms cold, the cold that
moderates heat, the coin that purchases all things, the balance and
weight that equals the shepherd with the king, and the simple with the
wise." Some animals dream as we do; Dogs, for instance, evidently dream
of the chase. With the lower animals which cannot shut their eyes it is,
however, more difficult to make sure whether they are awake or asleep. I
have often noticed insects at night, even when it was warm and light,
behave just as if they were asleep, and take no notice of objects which
would certainly have startled them in the day. The same thing has also
been observed in the case of fish.
But why should we sleep? What a remarkable thing it is that one-third of
our life should be passed in unconsciousness. "Half of our days," says
Sir T. Browne, "we pass in the shadow of the earth, and the brother of
death extracteth a third part of our lives." The obvious suggestion is
that we require rest. But this does not fully meet the case. In sleep
the mind is still awake, and lives a life of its own: our thoughts
wander, uncontrolled, by the will. The mind, therefore, is not
necessarily itself at rest; and yet we all know how it is refreshed by
sleep.
But though animals sleep, many of them are nocturnal in their habits.
Humboldt gives a vivid description of night in a Brazilian forest.
"Everything passed tranquilly till eleven at night, and then a noise so
terrible arose in the neighbouring forest that it was almost impossible
to close our eyes. Amid the cries of so many wild beasts howling at once
the Indians discriminated such only as were (at intervals) heard
separately. These were the little soft cries of the sapajous, the moans
of the alouate apes, the howlings of the jaguar and couguar, the peccary
and the sloth, and the cries of (many) birds. When the jaguars
approached the skirt of the forest our dog, which till then had never
ceased barking, began to howl and seek for shelter beneath our hammocks.
Sometimes, after a long silence, the cry of the tiger came from the tops
of the trees; and then it was followed by the sharp and long whistling
of the monkeys, which appeared to flee from the danger which threatened
them. We heard the same noises repeated during the course of whole
months whenever the forest approached the bed of the river.
"When the natives are interrogated on the causes of the tremendous noise
made by the beasts of the forest at certain hours of the night, the
answer is, they are keeping the feast of the full moon. I believe this
agitation is most frequently the effect of some conflict that has arisen
in the depths of the forest. The jaguars, for instance, pursue the
peccaries and the tapirs, which, having no defence, flee in close
troops, and break down the bushes they find in their way. Terrified at
this struggle, the timid and distrustful monkeys answer, from the tops
of the trees, the cries of the large animals. They awaken the birds that
live in society, and by degrees the whole assembly is in commotion. It
is not always in a fine moonlight, but more particularly at the time of
a storm of violent showers, that this tumult takes place among the wild
beasts. 'May heaven grant them a quiet night and repose, and us also!'
said the monk who accompanied us to the Rio Negro, when, sinking with
fatigue, he assisted in arranging our accommodation for the night."
Life is indeed among animals a struggle for existence, and in addition
to the more usual weapons--teeth and claws--we find in some animals
special and peculiar means of offence and defence.
If we had not been so familiarised with the fact, the possession of
poison might well seem a wonderful gift. That a fluid, harmless in one
animal itself, should yet prove so deadly when transferred to others, is
certainly very remarkable; and though the venom of the Cobra or the
Rattlesnake appeal perhaps more effectively to our imagination, we have
conclusive evidence of concentrated poison even in the bite of a midge,
which may remain for days perceptible. The sting of a Bee or Wasp,
though somewhat similar in its effect, is a totally different organ,
being a modified ovipositor. Some species of Ants do not sting in the
ordinary sense, but eject their acrid poison to a distance of several
inches.
Another very remarkable weapon is the electric battery of certain Eels,
of the Electric Cat Fish, and the Torpedoes, one of which is said to be
able to discharge an amount of electricity sufficient to kill a Man.
Some of the Medusæ and other Zoophytes are armed by millions of minute
organs known as "thread cells." Each consists of a cell, within which a
firm, elastic thread is tightly coiled. The moment the Medusa touches
its prey the cells burst and the threads spring out. Entering the flesh
as they do by myriads, they prove very effective weapons.
The ink of the Sepia has passed into a proverb. The animal possesses a
store of dark fluid, which, if attacked, it at once ejects, and thus
escapes under cover of the cloud thus created.
The so-called Bombardier Beetles, when attacked, discharge at the enemy,
from the hinder part of their body, an acrid fluid which, as soon as it
comes in contact with air, explodes with a sound resembling a miniature
gun. Westwood mentions, on the authority of Burchell, that on one
occasion, "whilst resting for the night on the banks of one of the
large South American rivers, he went out with a lantern to make an
astronomical observation, accompanied by one of his black servant boys;
and as they were proceeding, their attention was directed to numerous
beetles running about upon the shore, which, when captured, proved to be
specimens of a large species of Brachinus. On being seized they
immediately began to play off their artillery, burning and staining the
flesh to such a degree that only a few specimens could be captured with
the naked hand, and leaving a mark which remained a considerable time.
Upon observing the whitish vapour with which the explosions were
accompanied, the negro exclaimed in his broken English, with evident
surprise, 'Ah, massa, they make smoke!'"
Many other remarkable illustrations might be quoted; as for instance the
web of the Spider, the pit of the Ant Lion, the mephitic odour of the
Skunk.
SENSES
We generally attribute to animals five senses more or less resembling
our own. But even as regards our own senses we really know or
understand very little. Take the question of colour. The rainbow is
commonly said to consist of seven colours--red, orange, yellow, green,
blue, indigo, and violet.
But it is now known that all our colour sensations are mixtures of three
simple colours, red, green, and violet. We are, however, absolutely
ignorant how we perceive these colours. Thomas Young suggested that we
have three different systems of nerve fibres, and Helmholtz regards this
as "a not improbable supposition"; but so far as microscopical
examination is concerned, there is no evidence whatever for it.
Or take again the sense of Hearing. The vibrations of the air no doubt
play upon the drum of the ear, and the waves thus produced are conducted
through a complex chain of small bones to the fenestra ovalis and so to
the inner ear or labyrinth. But beyond this all is uncertainty. The
labyrinth consists mainly of two parts (1) the cochlea, and (2) the
semicircular canals, which are three in number, standing at right angles
to one another. It has been supposed that they enable us to maintain
the equilibrium of the body, but no satisfactory explanation of their
function has yet been given. In the cochlea, Corti discovered a
remarkable organ consisting of some four thousand complex arches, which
increase regularly in length and diminish in height. They are connected
at one end with the fibres of the auditory nerve, and Helmholtz has
suggested that the waves of sound play on them, like the fingers of a
performer on the keys of a piano, each separate arch corresponding to a
different sound. We thus obtain a glimpse, though but a glimpse, of the
manner in which perhaps we hear; but when we pass on to the senses of
smell and taste, all we know is that the extreme nerve fibres terminate
in certain cells which differ in form from those of the general surface;
but in what manner the innumerable differences of taste or smell are
communicated to the brain, we are absolutely ignorant.
If then we know so little about ourselves, no wonder that with reference
to other animals our ignorance is extreme.
We are too apt to suppose that the senses of animals must closely
resemble, and be confined to ours.
No one can doubt that the sensations of other animals differ in many
ways from ours. Their organs are sometimes constructed on different
principles, and situated in very unexpected places. There are animals
which have eyes on their backs, ears in their legs, and sing through
their sides.
We all know that the senses of animals are in many cases much more acute
than ours, as for instance the power of scent in the dog, of sight in
the eagle. Moreover, our eye is much more sensitive to some colours than
to others; least so to crimson, then successively to red, orange,
yellow, blue, and green; the sensitiveness for green being as much as
750 times as great as for red. This alone may make objects appear of
very different colours to different animals.
Nor is the difference one of degree merely. The rainbow, as we see it,
consists of seven colours--red, orange, yellow, green, blue, indigo, and
violet. But though the red and violet are the limits of the visible
spectrum, they are not the limits of the spectrum itself, there are
rays, though invisible to us, beyond the red at the one end, and beyond
the violet at the other: the existence of the ultra red can be
demonstrated by the thermometer; while the ultra violet are capable of
taking a photograph. But though the red and violet are respectively the
limits of our vision, I have shown[16] by experiments which have been
repeated and confirmed by other naturalists, that some of the lower
animals are capable of perceiving the ultra-violet rays, which to us are
invisible. It is an interesting question whether these rays may not
produce on them the impression of a new colour, or colours, differing
from any of those known to us.
So again with hearing, not only may animals in some cases hear better
than we do, but sounds which are beyond the reach of our ears, may be
audible to theirs. Even among ourselves the power of hearing shrill
sounds is greater in some persons than in others. Sound, as we know, is
produced by vibration of the air striking on the drum of the ear, and
the fewer are the vibrations in a second, the deeper is the sound, which
becomes shriller and shriller as the waves of sound become more rapid.
In human ears the limits of hearing are reached when about 35,000
vibrations strike the drum of the ear in a second.
Whatever the explanation of the gift of hearing in ourselves may be,
different plans seem to be adopted in the case of other animals. In many
Crustacea and Insects there are flattened hairs each connected with a
nerve fibre, and so constituted as to vibrate in response to particular
notes. In others the ear cavity contains certain minute solid bodies,
known as otoliths, which in the same way play upon the nerve fibres.
Sometimes these are secreted by the walls of the cavity itself, but
certain Crustacea have acquired the remarkable habit of selecting after
each moult suitable particles of sand, which they pick up with their
pincers and insert into their ears.
Many insects, besides the two large "compound" eyes one on each side of
the head, have between them three small ones, known as the "ocelli,"
arranged in a triangle. The structure of these two sets of eyes is quite
different. The ocelli appear to see as our eyes do. The lens throws an
inverted image on the back of the eye, so that with these eyes they must
see everything reversed, as we ourselves really do, though long practice
enables us to correct the impression. On the other hand, the compound
eyes consist of a number of facets, in some species as many as 20,000 in
each eye, and the prevailing impression among entomologists now is that
each facet receives the impression of one pencil of rays, that in fact
the image formed in a compound eye is a sort of mosaic. In that case,
vision by means of these eyes must be direct; and it is indeed difficult
to understand how an insect can obtain a correct impression when it
looks at the world with five eyes, three of which see everything
reversed, while the other two see things the right way up!
On the other hand, some regard each facet as an independent eye, in
which case many insects realise the epigram of Plato--
Thou lookest on the stars, my love,
Ah, would that I could be
Yon starry skies with thousand eyes,
That I might look on thee!
Even so, therefore, we only substitute one difficulty for another.
But this is not all. We have not only no proof that animals are confined
to our five senses, but there are strong reasons for believing that this
is not the case.
In the first place, many animals have organs which from their position,
structure, and rich supply of nerves, are evidently organs of sense; and
yet which do not appear to be adapted to any one of our five senses.
As already mentioned, the limits of hearing are reached when about
35,000 vibrations of the air strike on the drums of our ears. Light, as
was first conclusively demonstrated by our great countryman Young, is
the impression produced by vibration of the ether on the retina of the
eye. When 700 millions of millions of vibrations strike the eye in a
second, we see violet; and the colour changes as the number diminishes,
400 millions of millions giving us the impression of red.
Between 35 thousand and 400 millions of millions the interval is
immense, and it is obvious that there might be any number of sensations.
When we consider how greatly animals differ from us, alike in habits and
structure, is it not possible, nay, more, is it not likely that some of
these problematical organs are the seats of senses unknown to us, and
give rise to sensations of which we have no conception?
In addition to the capacity for receiving and perceiving, some animals
have the faculty of emitting light. In our country the glow-worm is the
most familiar case, though some other insects and worms have, at any
rate under certain conditions, the same power, and it is possible that
many others are really luminous, though with light which is invisible to
us. In warmer climates the Fire-fly, Lanthorn-fly, and many other
insects, shine with much greater brilliance, and in these cases the
glow seems to be a real love-light, like the lamp of Hero.
Many small marine animals, Medusæ, Crustacea, Worms, etc., are also
brilliantly luminous at night. Deep-sea animals are endowed also in many
cases with special luminous organs, to which I shall refer again.
SENSE OF DIRECTION
It has been supposed that animals possess also what has been called a
Sense of Direction. Many interesting cases are on record of animals
finding their way home after being taken a considerable distance. To
account for this fact it has been suggested that animals possess a sense
with which we are not endowed, or of which, at any rate, we possess only
a trace. The homing instinct of the pigeon has also been ascribed to the
same faculty. My brother Alfred, however, who has paid much attention to
pigeons, informs me that they are never taken any great distance at
once; but if they are intended to take a long flight, they are trained
to do so by stages.
Darwin suggested that it would be interesting to test the case by taking
animals in a close box, and then whirling them round rapidly before
letting them out. This is in fact done with cats in some parts of
France, when the family migrates, and is considered the only way of
preventing the cat from returning to the old home. Fabre has tried the
same thing with some wild Bees (Chalicodoma). He took some, marked them
on the back with a spot of white, and put them into a bag. He then
carried them a quarter of a mile, stopping at a point where an old cross
stands by the wayside, and whirled the bag rapidly round his head. While
he was doing so a good woman came by, who seemed not a little surprised
to find the Professor solemnly whirling a black bag round his head in
front of the cross; and, he fears, suspected him of Satanic practices.
He then carried his Bees a mile and a half in the opposite direction and
let them go. Three out of ten found their way home. He tried the same
experiment several times, in one case taking them a little over two
miles. On an average about a third of the Bees found their way home. "La
démonstration," says Fabre, "est suffisante. Ni les mouvements
enchevêtrés d'une rotation comme je l'ai décrite; ni l'obstacle de
collines à franchir et de bois à traverser; ni les embûches d'une voie
qui s'avance, rétrograde, et revient par un ample circuit, ne peuvent
troubler les Chalicodomes dépaysés et les empêcher de revenir au nid."
I must say, however, that I am not convinced. In the first place, the
distances were I think too short; and in the second, though it is true
that some of the Bees found their way home, nearly two-thirds failed to
do so. It would be interesting to try the experiment again, taking the
Bees say five miles. If they really possess any such sense, that
distance would be no bar to their return. I have myself experimented
with Ants, taking them about fifty yards from the nest, and I always
found that they wandered aimlessly about, having evidently not the
slightest idea of their way home. They certainly did not appear to
possess any "sense of direction."
NUMBER OF SPECIES