Charles H. Sylvester - "Journeys Through Bookland"

William Stearns Davis - "A Day In Old Athens"

George S. Boutwell - "Reminiscences of Sixty Years in Public Affairs, Vol. 2"

Marcel Proust - "A L'Ombre Des Jeunes Filles en Fleur, Volume 3"

Annual Bibliography of Commonwealth Literature 2007
This paper argues that discourses of love in Ghanaian market literature for youth offer a view into complex negotiations of agency and empowerment. Drawing on Deborah Durham's notion of youth as "social `shifters'" and Francis Nyamnjoh's conception of the "interconnectedness" of agency, I take Ghanaian market literature as one specific case of how African literature for youth foregrounds questions of continuity and change as African societies enter into increasingly complex global relations. In this literature for youth, received notions of love, often constructed out of impressions from American pop and hip hop music, carry new notions of agency that compete with existing "domesticated" forms. Authors like Ike Tandoh and Evelyn Tay employ discourses of love to offer youth alternative avenues for empowerment in a context of socio-economic disenfranchizement. In a creative process of "straddling", this writing both reveals and reproduces the contradictions that obtain in youth configurations of agency.

The Outline of Science, Vol. 1 (of 4)

J >> J. Arthur Thomson >> The Outline of Science, Vol. 1 (of 4)




The "floating sea-meadows," as Sir John Murray called them, are always
receiving contributions from inshore waters, where the conditions are
favourable for the prolific multiplication of unicellular Algae, and
there is also a certain amount of non-living sea-dust always being swept
out from the seaweed and sea-grass area.


Swimmers and Drifters

The animals of the open sea are conveniently divided into the active
swimmers (Nekton) and the more passive drifters (Plankton). The swimmers
include whales great and small, such birds as the storm petrel, the
fish-eating turtles and sea-snakes, such fishes as mackerel and herring,
the winged snails or sea-butterflies on which whalebone whales largely
feed, some of the active cuttles or squids, various open-sea prawns and
their relatives, some worms like the transparent arrow-worm, and such
active Protozoa as Noctiluca, whose luminescence makes the waves sparkle
in the short summer darkness. Very striking as an instance of the
insurgence of life are the sea-skimmers (Halobatidae), wingless insects
related to the water-measurers in the ditch. They are found hundreds of
miles from land, skimming on the surface of the open sea, and diving in
stormy weather. They feed on floating dead animals.

The drifters or easygoing swimmers--for there is no hard and fast
line--are represented, for instance, by the flinty-shelled Radiolarians
and certain of the chalk-forming animals (Globigerinid Foraminifera); by
jellyfishes, swimming-bells, and Portuguese men-of-war; by the
comb-bearers or Ctenophores; by legions of minute Crustaceans; by
strange animals called Salps, related to the sedentary sea-squirts; and
by some sluggish fishes like globe-fishes, which often float idly on the
surface.

Open-sea animals tend to be delicately built, with a specific gravity
near that of the sea-water, with adaptations, such as projecting
filaments, which help flotation, and with capacities of rising and
sinking according to the surrounding conditions. Many of them are
luminescent, and many of them are very inconspicuous in the water owing
to their transparency or their bluish colour. In both cases the
significance is obscure.


Hunger and Love

Hunger is often very much in evidence in the open sea, especially in
areas where the Plankton is poor. For there is great diversity in this
respect, most of the Mediterranean, for instance, having a scanty
Plankton as compared with the North Sea. In the South Pacific, west of
Patagonia, there is said to be an immense "sea desert" where there is
little Plankton, and therefore little in the way of fishes. The success
of fisheries in the North, e.g. on the Atlantic cod-banks, is due to the
richness of the floating sea-meadows and the abundance of the smaller
constituents of the animal Plankton.

Hunger is plain enough when the Baleen Whale rushes through the water
with open jaws, engulfing in the huge cavern of its mouth, where the
pendent whalebone plates form a huge sieve, incalculable millions of
small fry.

But there is love as well as hunger in the open sea. The maternal care
exhibited by the whale reaches a very high level, and the delicate shell
of the female Paper Nautilus or Argonaut, in which the eggs and the
young ones are sheltered, may well be described as "the most beautiful
cradle in the world."

Besides the permanent inhabitants of the open sea, there are the larval
stages of many shore-animals which are there only for a short time. For
there is an interesting give and take between the shore-haunt and the
open sea. From the shore come nutritive contributions and minute
organisms which multiply quickly in the open waters. But not less
important is the fact that the open waters afford a safe cradle or
nursery for many a delicate larva, e.g. of crab and starfish,
acorn-shell and sea-urchin, which could not survive for a day in the
rough-and-tumble conditions of the shore and the shallow water. After
undergoing radical changes and gaining strength, the young creatures
return to the shore in various ways.


III. THE DEEP SEA

Very different from all the other haunts are the depths of the sea,
including the floor of the abysses and the zones of water near the
bottom. This haunt, forever unseen, occupies more than a third of the
earth's surface, and it is thickly peopled. It came into emphatic notice
in connection with the mending of telegraph cables, but the results of
the _Challenger_ expedition (1873-6) gave the first impressive picture
of what was practically a new world.


Physical Conditions

The average depth of the ocean is about two and a half miles; therefore,
since many parts are relatively shallow, there must be enormous depths.
A few of these, technically called "deeps," are about six miles deep, in
which Mount Everest would be engulfed. There is enormous pressure in
such depths; even at 2,500 fathoms it is two and a half tons on the
square inch. The temperature is on and off the freezing-point of fresh
water (28 deg.-34 deg. Fahr.), due to the continual sinking down of cold water
from the Poles, especially from the South. Apart from the fitful gleams
of luminescent animals, there is utter darkness in the deep waters. The
rays of sunlight are practically extinguished at 250 fathoms, though
very sensitive bromogelatine plates exposed at 500 fathoms have shown
faint indications even at that depth. It is a world of absolute calm and
silence, and there is no scenery on the floor. A deep, cold, dark,
silent, monotonous world!


Biological Conditions

While some parts of the floor of the abysses are more thickly peopled
than others, there is no depth limit to the distribution of life.
Wherever the long arm of the dredge has reached, animals have been
found, e.g. Protozoa, sponges, corals, worms, starfishes, sea-urchins,
sea-lilies, crustaceans, lamp-shells, molluscs, ascidians, and fishes--a
very representative fauna. In the absence of light there can be no
chlorophyll-possessing plants, and as the animals cannot all be eating
one another there must be an extraneous source of food-supply. This is
found in the sinking down of minute organisms which are killed on the
surface by changes of temperature and other causes. What is left of
them, before or after being swallowed, and of sea-dust and mineral
particles of various kinds forms the diversified "ooze" of the
sea-floor, a soft muddy precipitate, which is said to have in places the
consistence of butter in summer weather.

There seems to be no bacteria in the abysses, so there can be no
rotting. Everything that sinks down, even the huge carcase of a whale,
must be nibbled away by hungry animals and digested, or else, in the
case of most bones, slowly dissolved away. Of the whale there are left
only the ear-bones, of the shark his teeth.


Adaptations to Deep-sea Life

In adaptation to the great pressure the bodies of deep-sea animals are
usually very permeable, so that the water gets through and through them,
as in the case of Venus' Flower Basket, a flinty sponge which a child's
finger would shiver. But when the pressure inside is the same as that
outside nothing happens. In adaptation to the treacherous ooze, so apt
to smother, many of the active deep-sea animals have very long,
stilt-like legs, and many of the sedentary types are lifted into safety
on the end of long stalks which have their bases embedded in the mud. In
adaptation to the darkness, in which there is only luminescence that
eyes could use, there is a great development of tactility. The
interesting problem of luminescence will be discussed elsewhere.

As to the origin of the deep-sea fauna, there seems no doubt that it
has arisen by many contributions from the various shore-haunts.
Following the down-drifting food, many shore-animals have in the course
of many generations reached the world of eternal night and winter, and
become adapted to its strange conditions. For the animals of the
deep-sea are as fit, beautiful, and vigorous as those elsewhere. There
are no slums in Nature.

[Illustration: THE BITTERLING (_Rhodeus Amarus_)

A Continental fish which lays its eggs by means of a long ovipositor
inside the freshwater mussel. The eggs develop inside the mollusc's
gill-plates.]

[Illustration: _Photo: W. S. Berridge._

WOOLLY OPOSSUM CARRYING HER FAMILY

One of the young ones is clinging to its mother and has its long
prehensile tail coiled round hers.]

[Illustration: SURINAM TOAD (_Pipa Americana_) WITH YOUNG ONES HATCHING
OUT OF LITTLE POCKETS ON HER BACK]

[Illustration: STORM PETREL OR MOTHER CAREY'S CHICKEN

(_Procellaria Pelagica_)

This characteristic bird of the open sea does not come to land at all
except to nest. It is the smallest web-footed bird, about four inches
long. The legs are long and often touch the water as the bird flies. The
storm petrel is at home in the Atlantic, and often nests on islands off
the west coast of Britain.]


IV. THE FRESH WATERS

Of the whole earth's surface the freshwaters form a very small fraction,
about a hundredth, but they make up for their smallness by their
variety. We think of deep lake and shallow pond, of the great river and
the purling brook, of lagoon and swamp, and more besides. There is a
striking resemblance in the animal population of widely separated
freshwater basins: and this is partly because birds carry many small
creatures on their muddy feet from one water-shed to another; partly
because some of the freshwater animals are descended from types which
make their way from the sea and the seashore through estuaries and
marshes, and only certain kinds of constitution could survive the
migration; and partly because some lakes are landlocked dwindling relics
of ancient seas, and similar forms again would survive the change.

A typical assemblage of freshwater animals would include many Protozoa,
like Amoebae and the Bell-Animalcules, a representative of one family
of sponges (Spongillidae), the common Hydra, many unsegmented worms
(notably Planarians and Nematodes), many Annelids related to the
earthworms, many crustaceans, insects, and mites, many bivalves and
snails, various fishes, a newt or two, perhaps a little mud-turtle or in
warm countries a huge Crocodilian, various interesting birds like the
water-ouzel or dipper, and mammals like the water-vole and the
water-shrew.

Freshwater animals have to face certain difficulties, the greatest of
which are drought, frost, and being washed away in times of flood.
There is no more interesting study in the world than an inquiry into the
adaptations by which freshwater animals overcome the difficulties of the
situation. We cannot give more than a few illustrations.

(1) Drought is circumvented by the capacity that many freshwater animals
have of lying low and saying nothing. Thus the African mudfish may spend
half the year encased in the mud, and many minute crustaceans can
survive being dried up for years. (2) Escape from the danger of being
frozen hard in the pool is largely due to the almost unique property of
water that it expands as it approaches the freezing-point. Thus the
colder water rises to the surface and forms or adds to the protecting
blanket of ice. The warmer water remains unfrozen at the bottom, and the
animals live on. (3) The risk of being washed away, e.g. to the sea, is
lessened by all sorts of gripping, grappling, and anchoring structures,
and by shortening the juvenile stages when the risks are greatest.


V. THE DRY LAND

Over and over again in the history of animal life there have been
attempts to get out of the water on to terra firma, and many of these
have been successful, notably those made (1) by worms, (2) by
air-breathing Arthropods, and (3) by amphibians.

In thinking of the conquest of the dry land by animals, we must
recognise the indispensable role of plants in preparing the way. The dry
ground would have proved too inhospitable had not terrestrial plants
begun to establish themselves, affording food, shelter, and humidity.
There had to be plants before there could be earthworms, which feed on
decaying leaves and the like, but how soon was the debt repaid when the
earthworms began their worldwide task of forming vegetable mould,
opening up the earth with their burrows, circulating the soil by means
of their castings, and bruising the particles in their
gizzard--certainly the most important mill in the world.

Another important idea is that littoral haunts, both on the seashore and
in the freshwaters, afforded the necessary apprenticeship and
transitional experience for the more strenuous life on dry land. Much
that was perfected on land had its beginnings on the shore. Let us
inquire, however, what the passage from water to dry land actually
implied. This has been briefly discussed in a previous article (on
Evolution), but the subject is one of great interest and importance.


Difficulties and Results of the Transition from Water to Land

Leaving the water for dry land implied a loss in freedom of movement,
for the terrestrial animal is primarily restricted to the surface of the
earth. Thus it became essential that movements should be very rapid and
very precise, needs with which we may associate the acquisition of fine
cross-striped, quickly contracting muscles, and also, in time, their
multiplication into very numerous separate engines. We exercise
fifty-four muscles in the half-second that elapses between raising the
heel of our foot in walking and planting it firmly on the ground again.
Moreover, the need for rapid precisely controlled movements implied an
improved nervous system, for the brain was a movement-controlling organ
for ages before it did much in the way of thinking. The transition to
terra firma also involved a greater compactness of body, so that there
should not be too great friction on the surface. An animal like the
jellyfish is unthinkable on land, and the elongated bodies of some land
animals like centipedes and snakes are specially adapted so that they do
not "sprawl." They are exceptions that prove the rule.

Getting on to dry land meant entering a kingdom where the differences
between day and night, between summer and winter are more felt than in
the sea. This made it advantageous to have protections against
evaporation and loss of heat and other such dangers. Hence a variety of
ways in which the surface of the body acquired a thickened skin, or a
dead cuticle, or a shell, or a growth of hair, and so forth. In many
cases there is an increase of the protection before the winter sets in,
e.g. by growing thicker fur or by accumulating a layer of fat below the
skin.

But the thickening or protection of the skin involved a partial or total
loss of the skin as a respiratory surface. There is more oxygen
available on dry land than in the water, but it is not so readily
captured. Thus we see the importance of moist internal surfaces for
capturing the oxygen which has been drawn into the interior of the body
into some sort of lung. A unique solution was offered by Tracheate
Arthropods, such as Peripatus, Centipedes, Millipedes, and Insects,
where the air is carried to every hole and corner of the body by a
ramifying system of air-tubes or tracheae. In most animals the blood goes
to the air, in insects the air goes to the blood. In the Robber-Crab,
which has migrated from the shore inland, the dry air is absorbed by
vascular tufts growing under the shelter of the gill-cover.

The problem of disposing of eggs or young ones is obviously much more
difficult on land than in the water. For the water offers an immediate
cradle, whereas on the dry land there were many dangers, e.g. of
drought, extremes of temperature, and hungry sharp-eyed enemies, which
had to be circumvented. So we find all manner of ways in which land
animals hide their eggs or their young ones in holes and nests, on herbs
and on trees. Some carry their young ones about after they are born,
like the Surinam toad and the kangaroo, while others have prolonged the
period of ante-natal life during which the young ones develop in safety
within their mother, and in very intimate partnership with her in the
case of the placental mammals. It is very interesting to find that the
pioneer animal called Peripatus, which bridges the gap between worms and
insects, carries its young for almost a year before birth.

Enough has been said to show that the successive conquests of the dry
land had great evolutionary results. It is hardly too much to say that
the invasion which the Amphibians led was the beginning of better
brains, more controlled activities, and higher expressions of family
life.

[Illustration: ALBATROSS: A CHARACTERISTIC PELAGIC BIRD OF THE SOUTHERN
SEA

It may have a spread of wing of over 11 feet from tip to tip. It is
famous for its extraordinary power of "sailing" round the ship without
any apparent strokes of its wings.]


VI. THE AIR

There are no animals thoroughly aerial, but many insects spend much of
their adult life in the free air, and the swift hardly pauses in its
flight from dawn to dusk of the long summer day, alighting only for
brief moments at the nest to deliver insects to the young. All the
active life of bats certainly deserves to be called aerial.

The air was the last haunt of life to be conquered, and it is
interesting to inquire what the conquest implied. (1) It meant
transcending the radical difficulty of terrestrial life which confines
the creatures of the dry land to moving on one plane, the surface of the
earth. But the power of flight brought its possessors back to the
universal freedom of movement which water animals enjoy. When we watch a
sparrow rise into the air just as the cat has completed her stealthy
stalking, we see that flight implies an enormous increase of safety. (2)
The power of flight also opened up new possibilities of following the
prey, of exploring new territories, of prospecting for water. (3) Of
great importance too was the practicability of placing the eggs and the
young, perhaps in a nest, in some place inaccessible to most enemies.
When one thinks of it, the rooks' nests swaying on the tree-tops express
the climax of a brilliant experiment. (4) The crowning advantage was the
possibility of migrating, of conquering time (by circumventing the arid
summer and the severe winter) and of conquering space (by passing
quickly from one country to another and sometimes almost girdling the
globe). There are not many acquisitions that have meant more to their
possessors than the power of flight. It was a key opening the doors of a
new freedom.

The problem of flight, as has been said in a previous chapter, has been
solved four times, and the solution has been different in each case. The
four solutions are those offered by insects, extinct Pterodactyls,
birds, and bats. Moreover, as has been pointed out, there have been
numerous attempts at flight which remain glorious failures, notably the
flying fishes, which take a great leap and hold their pectoral fins
taut; the Flying Tree-Toad, whose webbed fingers and toes form a
parachute; the Flying Lizard (_Draco volans_), which has its skin pushed
out on five or six greatly elongated mobile ribs; and various "flying"
mammals, e.g. Flying Phalangers and Flying Squirrels, which take great
swooping leaps from tree to tree.

The wings of an insect are hollow flattened sacs which grow out from the
upper parts of the sides of the second and third rings of the region
called the thorax. They are worked by powerful muscles, and are
supported, like a fan, by ribs of chitin, which may be accompanied by
air-tubes, blood-channels, and nerves. The insect's body is lightly
built and very perfectly aerated, and the principle of the insect's
flight is the extremely rapid striking of the air by means of the
lightly built elastic wings. Many an insect has over two hundred strokes
of its wings in one _second_. Hence, in many cases, the familiar hum,
comparable on a small scale to that produced by the rapidly revolving
blades of an aeroplane's propeller. For a short distance a bee can
outfly a pigeon, but few insects can fly far, and they are easily blown
away or blown back by the wind. Dragon-flies and bees may be cited as
examples of insects that often fly for two or three miles. But this is
exceptional, and the usual shortness of insect flight is an important
fact for man since it limits the range of insects like house-flies and
mosquitoes which are vehicles of typhoid fever and malaria respectively.
The most primitive insects (spring-tails and bristle-tails) show no
trace of wings, while fleas and lice have become secondarily wingless.
It is interesting to notice that some insects only fly once in their
lifetime, namely, in connection with mating. The evolution of the
insect's wing remains quite obscure, but it is probable that insects
could run, leap, and parachute before they could actually fly.

The extinct Flying Dragons or Pterodactyls had their golden age in the
Cretaceous era, after which they disappeared, leaving no descendants. A
fold of skin was spread out from the sides of the body by the enormously
elongated outermost finger (usually regarded as corresponding to our
little finger); it was continued to the hind-legs and thence to the
tail.

It is unlikely that the Pterodactyls could fly far, for they have at
most a weak keel on their breast-bone; on the other hand, some of them
show a marked fusion of dorsal vertebrae, which, as in flying birds, must
have served as a firm fulcrum for the stroke of the wings. The quaint
creatures varied from the size of a sparrow up to a magnificent spread
of 15-20 feet from tip to tip of the wings. They were the largest of all
flying creatures.

The bird's solution of the problem of flight, which will be discussed
separately, is centred in the feather, which forms a coherent vane for
striking the air. In Pterodactyl and bat the wing is a web-wing or
patagium, and a small web is to be seen on the front side of the bird's
wing. But the bird's patagium is unimportant, and the bird's wing is on
an evolutionary tack of its own--a fore-limb transformed for bearing the
feathers of flight. Feathers are in a general way comparable to the
scales of reptiles, but only in a general way, and no transition stage
is known between the two. Birds evolved from a bipedal Dinosaur stock,
as has been noticed already, and it is highly probable that they began
their ascent by taking running leaps along the ground, flapping their
scaly fore-limbs, and balancing themselves in kangaroo-like fashion with
an extended tail. A second chapter was probably an arboreal
apprenticeship, during which they made a fine art of parachuting--a
persistence of which is to be seen in the pigeon "gliding" from the
dovecot to the ground. It is in birds that the mastery of the air
reaches its climax, and the mysterious "sailing" of the albatross and
the vulture is surely the most remarkable locomotor triumph that has
ever been achieved. Without any apparent stroke of the wings, the bird
sails for half an hour at a time with the wind and against the wind,
around the ship and in majestic spirals in the sky, probably taking
advantage of currents of air of different velocities, and continually
changing energy of position into energy of motion as it sinks, and
energy of motion into energy of position as it rises. It is interesting
to know that some dragon-flies are also able to "sail."

The web-wing of bats involves much more than the fore-arm. The double
fold of skin begins on the side of the neck, passes along the front of
the arm, skips the thumb, and is continued over the elongated palm-bones
and fingers to the sides of the body again, and to the hind-legs, and to
the tail if there is a tail. It is interesting to find that the bones of
the bat's skeleton tend to be lightly built as in birds, that the
breast-bone has likewise a keel for the better insertion of the pectoral
muscles, and that there is a solidifying of the vertebrae of the back,
affording as in birds a firm basis for the wing action. Such similar
adaptations to similar needs, occurring in animals not nearly related to
one another, are called "convergences," and form a very interesting
study. In addition to adaptations which the bat shares with the flying
bird, it has many of its own. There are so many nerve-endings on the
wing, and often also on special skin-leaves about the ears and nose,
that the bat flying in the dusk does not knock against branches or other
obstacles. Some say that it is helped by the echoes of its high-pitched
voice, but there is no doubt as to its exquisite tactility. That it
usually produces only a single young one at a time is a clear adaptation
to flight, and similarly the sharp, mountain-top-like cusps on the back
teeth are adapted in insectivorous bats for crunching insects.

Whether we think of the triumphant flight of birds, reaching a climax in
migration, or of the marvel that a creature of the earth--as a mammal
essentially is--should evolve such a mastery of the air as we see in
bats, or even of the repeated but splendid failures which parachuting
animals illustrate, we gain an impression of the insurgence of living
creatures in their characteristic endeavour after fuller well-being.

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