CHAPTER X.

In his later years honours poured thick upon Darwin. In 1871 he received

the Prussian order of knighthood "For Merit"; and was elected a

corresponding member of the Austrian Academy of Sciences. In 1877

Cambridge University, making an exception to its custom of not

conferring honorary degrees on its members, gave him the LL.D. and an

ovation, when the kindly eyes of the venerable naturalist beamed upon

the monkey-figure dangled by undergraduates before him from the

galleries, in addition to a solitary link of a huge chain, no doubt

representing "the missing link." In 1878 the honour, long withheld, and

certainly unsought, of being elected a corresponding member of the Paris

Academy of Sciences in the section of Zoology, was his; and that tardy

body recognised late the man whose supremacy in science it had done

nothing either to foster or to approve. In 1879 the Baly Medal of the

London College of Physicians was awarded to him.

After the Cambridge celebration a subscription was raised to obtain a

portrait of the veteran evolutionist, which was executed by Mr. W. B.

Richmond, and now adorns the Philosophical Library of the New Museums at

Cambridge. Later, yet another portrait--the finest in his own and many

others' belief--was painted by Mr. John Collier, and presented to

the Linnean Society, which will always be associated with the first

announcement of Darwin's main theory, as well as with many others of his

scientific discoveries.

Professor Haeckel has given the following charming description of Darwin

and his home surroundings in his later years: "In Darwin's own carriage,

which he had thoughtfully sent for my convenience to the railway

station, I drove, one sunny morning in October, through the graceful,

hilly landscape of Kent, that with the chequered foliage of its woods,

with its stretches of purple heath, yellow broom, and evergreen oaks,

was arrayed in its fairest autumnal dress. As the carriage drew up in

front of Darwin's pleasant country house, clad in a vesture of ivy and

embowered in elms, there stepped out to meet me from the shady porch,

overgrown with creeping plants, the great naturalist himself, a tall and

venerable figure, with the broad shoulders of an Atlas supporting a

world of thought, his Jupiter-like forehead highly and broadly arched,

as in the case of Goethe, and deeply furrowed with the plough of mental

labour; his kindly, mild eyes looking forth under the shadow of

prominent brows; his amiable mouth surrounded by a copious silver-white

beard. The cordial, prepossessing expression of the whole face, the

gentle, mild voice, the slow, deliberate utterance, the natural and

naive train of ideas which marked his conversation, captivated my whole

heart in the first hour of our meeting, just as his great work had

formerly, on my first reading it, taken my whole understanding by storm,

I fancied a lofty world-sage out of Hellenic antiquity--a Socrates or

Aristotle--stood before me."

The well-known botanist, Alphonse de Candolle, thus describes a visit to

Down:

"I longed to converse once more with Darwin, whom I had seen in

1839, and with whom I kept up a most interesting correspondence. It

was on a fine autumn morning in 1880 that I arrived at Orpington

station, where my illustrious friend's break met me. I will not

here speak of the kind reception given to me at Down, and of the

pleasure I felt in chatting familiarly with Mr. and Mrs. Darwin and

their son Francis. I note only that Darwin at seventy was more

animated and appeared happier than when I had seen him forty-one

years before. His eye was bright and his expression cheerful,

whilst his photographs show rather the shape of his head, like that

of an ancient philosopher. His varied, frank, gracious

conversation, entirely that of a gentleman, reminded me of that of

Oxford and Cambridge _savants_. The general tone was like his

books, as is the case with sincere men, devoid of every trace of

charlatanism. He expressed himself in English easily understood by

a foreigner, more like that of Bulwer or Macaulay, than that of

Dickens or Carlyle. I asked him for news of the committee, of which

he was a member, for reforming English spelling, and when I said

that moderate changes would be best received by the public, he

laughingly said, 'As for myself, _of course_, I am for the most

radical changes.' We were more in accord on another point, that a

man of science, even up to advanced age, ought to take an interest

in new ideas, and to accept them, if he finds them true. 'That was

very strongly the opinion of my friend Lyell,' he said; 'but he

pushed it so far as sometimes to yield to the first objection, and

I was then obliged to defend him against himself.' Darwin had more

firmness in his opinions, whether from temperament, or because he

had published nothing without prolonged reflection.

"Around the house no trace appeared to remain of the former labours

of the owner. Darwin used simple means. He was not one who would

have demanded to have palaces built in order to accommodate

laboratories. I looked for the greenhouse in which such beautiful

experiments on hybrid plants had been made. It contained only a

vine. One thing struck me, although it is not rare in England,

where animals are loved. A heifer and a colt were feeding close to

us with the tranquillity which tells of good masters, and I heard

the joyful barking of dogs. 'Truly,' I said to myself, 'the history

of the variations of animals was written here, and observations

must be going on, for Darwin is never idle.' I did not suspect that

I was walking above the dwellings of those lowly beings called

earthworms, the subject of his last work, in which Darwin showed

once more how little causes in the long run produce great effects.

He had been studying them for thirty years, but I did not know it.

"Returning to the house, Darwin showed me his library, a large room

on the ground floor, very convenient for a studious man; many books

on the shelves; windows on two sides; a writing-table and another

for apparatus for his experiments. Those on the movements of stems

and roots were still in progress. The hours passed like minutes. I

had to leave. Precious memories of that visit remain."

Yet once more, in 1881, the famous publishing house of Murray issued a

new work--his last--by the great illuminator of Nature. Its subject was

one which no one save those who knew him could have expected. It dealt

with "The Formation of Vegetable Mould, through the Action of Worms,

with Observations on their Habits," and in it the lowly earthworm was at

last raised to its true rank as the genuine preparer and possessor of

the soil. Both Gilbert White and Edward Jenner had been impressed with

the work earthworms do in nature, but no one had written extensively on

the subject till Darwin himself, in 1837, read a short paper on the

"Formation of Mould" before the Geological Society of London (published

in the fifth volume of the Society's Transactions), showing that small

fragments of burnt marl, cinders, &c., which had been thickly strewed

over the surface of several meadows, were found after a few years lying

at the depth of some inches beneath the turf. It was suggested to him by

his relative Mr. Wedgwood, of Maer Hall, in Staffordshire, that this was

due to the quantity of fine earth continually brought up to the surface

by worms in the form of castings. Observation and experiment were to

settle the question in the usual Darwinian manner, and many a portion of

soil was watched. One experiment lasted nearly thirty years, for a

quantity of broken chalk and sifted coal cinders was spread on December

20, 1842, over distinct parts of a field near Down House, which had

existed as pasture for a very long time. At the end of November, 1871, a

trench was dug across this part of the field, and the nodules of chalk

were found buried seven inches. A similar change took place in a field

covered with flints, where in thirty years the turf was compact without

any stones. A pathway formed of loose-set flagstones was similarly

buried by worms, and became undistinguishable from the rest of the lawn.

And these are but a few of the evidences of the wonderful action of

worms, collected by the activity of Charles Darwin and his sons.

Earthworms were not only scrutinised in their out-of-door work, but were

kept in confinement and studied. It appears they swallow earth both to

make their burrows and to extract all nutriment it may contain; they

will eat almost anything they can get their skin over. From careful

calculation it was shown that worms on an average pass ten tons of the

soil on an acre of ground through their bodies every year. It is, then,

but a truism to say that every bit of soil on the surface of the globe

must have passed through their bodies many times. They were discovered

to work mainly by night, when hundreds may with care be discerned, with

tails fixed in their burrows, prowling round in circles, rapidly

retreating into holes, and strongly resisting efforts to extract them.

It was found by careful study that they have no sense of hearing, but a

most remarkable sensitiveness to vibrations of the earth or even

to contact with air in motion. No book Darwin wrote was fuller of

interesting and undoubtedly correct observations.

In concluding, the author enforces the claims of worms on the gratitude

of archæologists, as they protect and preserve for an indefinitely long

period every object not liable to decay which is dropped on the surface

of the land, by burying it beneath their castings. It is thus that many

tesselated pavements and other ancient remains have been preserved; but,

on the other hand, worms have undermined many old massive walls and

caused them to subside, and no building is in this respect safe unless

the foundations are at least six or seven feet beneath the surface,

below which depth worms cannot work. Worms also prepare the ground in an

excellent manner for plant life, periodically exposing the mould to the

air, sifting it so that no stones larger than the particles they can

swallow are left in it, mingling the whole intimately together, burying

all decaying objects within reach of the roots of the plants, allowing

air to penetrate deeply into the earth. "When we behold a wide,

turf-covered expanse, we should remember that its smoothness, on which

so much of its beauty depends, is mainly due to all the inequalities

having been slowly levelled by worms. It is a marvellous reflection that

the whole of the superficial mould over any such expanse has passed, and

will again pass, every few years through the bodies of worms. The plough

is one of the most ancient and most valuable of man's inventions; but

long before he existed the land was in fact regularly ploughed, and

still continues to be thus ploughed by earthworms. It may be doubted

whether there are many other animals which have played so important

a part in the history of the world, as have these lowly organised

creatures."

After this last book Darwin felt much exhausted, and wrote: "I feel

so worn out that I do not suppose I shall ever again give reviewers

trouble." His brother Erasmus's death in the same year was the severance

of a link with early days. Yet for some months he continued in a

moderate degree of health, still working. For some weeks however in the

following March and April he was slightly unwell, and the action of his

heart became so weak that he was not allowed to mount the stairs. On

Tuesday, April 18, he was in his study examining a plant which he had

had brought to him, and he read the same evening before retiring. Till

the day of his death he did not become seriously ill. On that day the

heart, which had so long done its duty, failed, and about 4 p.m.,

on April 19, 1882, Charles Darwin breathed his last in peace, aged

seventy-three years, two months, and seven days.

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