A great many trees have lately been cut down in Kensington Gardens, and
the subject was brought before the House of Commons at the latter part
of its last session. In reply to Mr. Ritchie’s question, Mr. Adam, the
then First Commissioner of Works, made explanations which, so far as
they go, are satisfactory—but the distance is very small. He states
that all who have watched the trees must have seen that their decay
“has become rapid and decided in the last two years,” that when the
vote for the parks came on many “were either dead or hopelessly dying,”
that in the more thickly planted portions of the gardens the trees were
dead and dying by hundreds, owing to the impoverished soil and the
terrible neglect of timely thinning fifty or sixty years ago.
Knowing the sensitiveness of the public regarding tree-cutting, Mr.
Adam obtained the co-operation of a committee of experts, consisting
of Sir Joseph Hooker, Mr. Clutton, and Mr. Thomas, “so distinguished
as a landscape gardener,” and the late First Commissioner of Works.
They had several meetings, and, as Mr. Adam informs us, “the result has
been a unanimous resolution that we ought to proceed at once to clear
away the dead and dying trees.” This is being done to the extent of “an
absolute clearance” in some places, and the removal of numerous trees
all over the gardens. We are further told that “the spaces cleared will
either be trenched, drained, and replanted, or will be left open, as
may appear best.” Mr. Adam adds that “the utmost care is being used in
the work; that not a tree is being cut that can properly be spared; and
that every effort will be made to restore life to the distinguished
trees that are dying.”
I have watched the proceedings in Kensington Gardens and also in Bushey
Park, and have considerable difficulty in describing the agricultural
vandalism there witnessed, and expressing my opinion on it, without
transgressing the bounds of conventional courtesy towards those who are
responsible. I do not refer to the cutting down of the dead and dying
trees, but to the proceedings by which they have been officially and
artificially killed by those who ought to possess sufficient knowledge
of agricultural chemistry to understand the necessary consequences of
their conduct.
About forty years have elapsed since Liebig taught to all who were able
and willing to learn that trees and other vegetables are composed of
two classes of material: 1st, the carbon and elements of water derived
from air and rain; and 2d, the nitrogenous and incombustible saline
compounds derived from the soil. The possible atmospheric origin of
some of the nitrogen is still under debate, but there is no doubt that
all which remains behind as incombustible ash, when we burn a leaf, is
so much matter taken out of the soil. Every scientific agriculturist
knows that certain crops take away certain constituents from the soil,
and that if this particular cropping continues without a replacing of
those particular constituents of fertility, the soil must become barren
in reference to the crop in question, though other crops demanding
different food may still grow upon it.
The agricultural vandalism that I have watched with so much vexation
is the practice of annually raking and sweeping together the fallen
leaves, collecting them in barrows and carts, and then carrying them
quite away from the soil in which the trees are growing, or should
grow. I have inquired of the men thus employed whether they put
anything on the ground to replace these leaves, and they have not
merely replied in the negative, but have been evidently surprised at
such a question being asked. What is finally done with the leaves I
do not know; they may be used for the flower-beds or sold to outside
florists. I have seen a large heap accumulated near to the Round Pond.
Now, the leaves of forest trees are just those portions containing the
largest proportion of ash; or, otherwise stated, they do the most in
exhausting the soil. In Epping Forest, in the New Forest, and other
forests where there has been still more “terrible neglect of timely
thinning,” the trees continue to grow vigorously, and have thus grown
for centuries; the leaves fall on the soil wherein the trees grow, and
thus continually return to it all they have taken away.
They do something besides this. During the winter they gradually decay.
This decay is a process of slow combustion, giving out just as much
heat as though all the leaves were gathered together and used as fuel
for a bonfire; but the heat in the course of natural decay is gradually
given out just when and where it is wanted, and the coating of leaves,
moreover, forms a protecting winter jacket to the soil.
I am aware that the plea for this sweeping-up of leaves is the demand
for tidiness; that people with thin shoes might wet their feet if they
walked through a stratum of fallen leaves. The reply to this is that
all reasonable demands of this class would be satisfied by clearing
the footpaths, from which nobody should deviate _in the winter time_.
Before the season for strolling in the grass returns, Nature will
have disposed of the fallen leaves. A partial remedy may be applied
by burning the leaves, then carefully distributing their ashes; but
this is after all a clumsy imitation of the natural slow combustion
above described, and is wasteful of the ammoniacal salts as well as
of the heat. The avenues of Bushey Park are not going so rapidly as
the old sylvan glories of Kensington Gardens, though the same robbery
of the soil is practiced in both places. I have a theory of my own
in explanation of the difference, viz., that the cloud of dust that
may be seen blowing from the roadway as the vehicles drive along the
Chestnut Avenue of Bushey Park, settles down on one side or the other,
and supplies material which to some extent, but not sufficiently,
compensates for the leaf-robbery.
The First Commissioner speaks of efforts being made to restore life to
the distinguished trees that are dying. Let us hope that these include
a restoration to the soil of those particular salts that have for
some years past been annually carted away from it in the form of dead
leaves, and that this is being done not only around the “distinguished”
trees, but throughout the gardens.
Any competent analytical chemist may supply Mr. Adam with a statement
of what are these particular salts. This information is obtainable by
simply burning an average sample of the leaves and analyzing their
ashes.
While on this subject I may add a few words on another that is
closely connected with it. In some parts of the parks gardeners may
be seen more or less energetically occupied in pushing and pulling
mowing-machines; and carrying away the grass which is thus cut. This
produces the justly admired result of a beautiful velvet lawn; but
unless the continuous exhaustion of the soil is compensated, a few
years of such cropping will starve it. This subject is now so well
understood by all educated gardeners that it should be impossible to
suppose it to be overlooked in our parks, as it is so frequently in
domestic gardening. Many a lawn that a few years ago was the pride
of its owner is now becoming as bald as the head of the faithful,
“practical,” and obstinate old gardener who so heartily despises the
“fads” of scientific theorists.
When natural mowing-machines are used, _i.e._, cattle and sheep, their
droppings restore all that they take away from the soil, minus the
salts contained in their own flesh, or the milk that may be removed. An
interesting problem has been for some time past under the consideration
of the more scientific of the Swiss agriculturists. From the mountain
pasturages only milk is taken away, but this milk contains a certain
quantity of phosphates, the restoration of which must be effected
sooner or later, or the produce will be cut off, especially now that so
much condensed milk is exported.
The wondrously rich soil of some parts of Virginia has been exhausted
by unrequited tobacco crops. The quantity of ash displayed on the
burnt end of a cigar demonstrates the exhausting character of tobacco
crops. That which the air and water supplied to the plant is returned
as invisible gases during combustion, but all the ash that remains
represents what the leaves have taken from the soil, and what should be
restored in order to sustain its pristine fertility.
The West India Islands have similarly suffered to a very serious extent
on account of the former ignorance of the sugar planters, who used
the canes as fuel in boiling down the syrup, and allowed the ashes of
those canes to be washed into the sea. They were ignorant of the fact
that pure sugar maybe taken away in unlimited quantities without any
impoverishment of the land, seeing that it is composed merely of carbon
and the elements of water, all derivable from air and rain. All that is
needed to maintain the perennial fertility of a sugar plantation is to
restore the stems and leaves of the cane, or carefully to distribute
their ashes.
The relation of these to the soil of the sugar plantations is precisely
the same as that of the leaves of the trees to the soil of Kensington
Gardens, and the reckless removal of either must produce the same
disastrous consequences.
THE OLEAGINOUS PRODUCTS OF THAMES MUD: WHERE THEY COME FROM AND WHERE
THEY GO.
Once upon a time—and not a very long time since—a French chemist left
the land of superexcellence, and crossed to the shores of foggy Albion.
He proceeded to Yorkshire, his object being to make his fortune. He
was so presumptuous as to believe that he might do this by picking up
something which Yorkshiremen threw away. That something was soapsuds.
His chemistry taught him that soap is a compound of fat and alkali,
and that if a stronger acid than that belonging to the fat is added to
soapsuds, the stronger acid will combine with the alkali and release
the fat, the which fat thus liberated will float upon the surface of
the liquid, and may then be easily skimmed off, melted together, and
sold at a handsome profit.
But why leave the beautiful France and desolate himself in dreary
Yorkshire merely to do this? His reason was, that the cloth workers
of Yorkshire use tons and tons of soap for scouring their materials,
and throw away millions of gallons of soapsuds. Besides this, there
are manufactories of sulphuric acid near at hand, and a large demand
for machinery grease just thereabouts. He accordingly bought iron
tanks, and erected works in the midst of the busiest centre of the
woolen manufacture. But he did not make his fortune all at once. On the
contrary, he failed to pay expenses, for in his calculations he had
omitted to allow for the fact that the soap liquor is much diluted, and
therefore he must carry much water in order to obtain a little fat.
This cost of carriage ruined his enterprise, and his works were offered
for sale.
The purchaser was a shrewd Yorkshireman, who then was a dealer in
second-hand boilers, tanks, and other iron wares. When he was about to
demolish the works, the Frenchman took him into confidence, and told
the story of his failure. The Yorkshireman said little, but thought
much; and having finally assured himself that the carriage was the
only difficulty, he concluded, after the manner of Mahomet, that if the
mountain would not come to him, he might go to the mountain; and then
made an offer of partnership on the basis that the Frenchman should do
the chemistry of the work, and that he (the Yorkshireman) should do the
rest.
Accordingly, he went to the works around, and offered to contract for
the purchase of all their soapsuds, if they would allow him to put up a
tank or two on their premises. This he did; the acid was added, the fat
rose to the surface, was skimmed off, and carried, _without the water_,
to the central works, where it was melted down, and, with very little
preparation, was converted into “cold-neck grease,” and “hot-neck
grease,” and used, besides, for other lubricating purposes. The
Frenchman’s science and skill, united with the Yorkshireman’s practical
sagacity, built up a flourishing business, and the grease thus made is
still in great demand and high repute for lubricating the rolling-mills
of iron works, and for many other kinds of machinery.
My readers need not be told that there are soapsuds in London as well
as in Yorkshire, and they also know that the London soapsuds pass
down the drains into the sewers. I may tell them that besides this
there are many kinds of acids also passed into London sewers, and that
others are generated by the decompositions there abounding. These acids
do the Frenchman’s work upon the London soapsuds, but the separated
fat, instead of rising slowly and undisturbed to form a film upon the
surface of the water, is rolled and tumbled amongst its multifarious
companion filth, and it sticks to whatever it may find congenial to
itself. Hairs, rags, wool, ravellings of cotton, and fibres of all
kinds are especially fraternal to such films of fat: they lick it up
and stick it about and amid themselves; and as they and the fat roll
and tumble along the sewers together, they become compounded and shaped
into unsavory balls that are finally deposited on the banks of the
Thames, and quietly repose in its hospitable mud.
But there is no peace even there, and the gentle rest of the fat
nodules is of short duration. The mud-larks are down upon them, in
spite of all their burrowing; they are gathered up and melted down. The
filthiest of their associated filth is thus removed, and then, and with
a very little further preparation, they appear as cakes of dark-colored
hard fat, very well suited for lubricating machinery, and indifferently
fit for again becoming soap, and once more repeating their former
adventures.
Those gentlemen of the British press whose brilliant imagination
supplies the public with their intersessional harvests of sensational
adulteration panics, have obtained a fertile source of paragraphs by
co-operating with the mud-larks in the manufacture of butter from
Thames mud.
The origin of these stories is traceable to certain officers of the
Thames police, who, having on board some of these gentlemen of the
press engaged in hunting up information respecting a body found in
the river, supplied their guests with a little supplementary chaff by
showing them a mud-lark’s gatherings, and telling them that it was raw
material from which “fine Dorset” is produced. A communication from
“Our Special Correspondent” on the manufacture of butter from Thames
mud accordingly appeared in the atrocity column on the following
morning, and presently “went the round of the papers.”
Although it is perfectly possible by the aid of modern chemical skill
to refine even such filth as this, and to churn it into a close
resemblance to butter, the cost of doing so would exceed the highest
price obtainable for the finest butter that comes to the London
market. A skillful chemist can convert all the cotton fibres that are
associated with this sewage fat into pure sugar or sugar-candy, but the
manufacture of sweetmeats from Thames mud would not pay any better than
the production of butter from the same source, and for the same reason.
Mutton-suet, chop-parings, and other clean, wholesome fat can be bought
wholesale for less than fivepence per pound. It would cost above three
times as much as this to bring the fat nodules of the Thames mud to as
near an approach to butter as this sort of fat. Therefore the Thames
mud-butter material would be three times as costly as that obtainable
from the butcher. While the supply of mutton-suet is so far in excess
of the butter-making demand that tons of it are annually used in the
North for lubricating machinery, we need not fear that anything less
objectionable—_i.e._, more costly to purify—will be used as a butter
substitute.