INSECT MANUFACTURES.
PUBLISHED UNDER THE DIRECTION OF THE COMMITTEE OF GENERAL LITERATURE AND
EDUCATION, APPOINTED BY THE SOCIETY FOR PROMOTING CHRISTIAN KNOWLEDGE.
LONDON:
PRINTED FOR THE
SOCIETY FOR PROMOTING CHRISTIAN KNOWLEDGE.
SOLD AT THE DEPOSITORY,
GREAT QUEEN STREET, LINCOLN’S INN FIELDS
AND 4, ROYAL EXCHANGE.
1847.
LONDON
R. CLAY, PRINTER, BREAD STREET HILL.
[Illustration: INSECT MANUFACTURES]
CONTENTS.
Page
INTRODUCTION 3
CHAPTER I.
MANUFACTURE OF SILK BY CATERPILLARS OF VARIOUS KINDS 9
CHAPTER II.
MANUFACTURE OF SILK BY THE SILKWORM 31
CHAPTER III.
MANUFACTURE OF SILK BY SPIDERS 55
CHAPTER IV.
MANUFACTURE OF WAX BY THE HIVE BEE, THE HUMBLE BEE, AND THE WHITE
WAX INSECT OF CHINA 73
CHAPTER V.
MANUFACTURE OF HONEY BY THE HIVE BEE 99
CHAPTER VI.
MANUFACTURE OF COCHINEAL BY THE COCCUS CACTI, OR COCHINEAL INSECT 113
CHAPTER VII.
MANUFACTURE OF GUM LAC BY THE LAC INSECT 133
CHAPTER VIII.
MANUFACTURE OF NUT GALLS BY THE GALL INSECT 143
CHAPTER IX.
OTHER INSECT PRODUCTIONS USEFUL TO MAN 154
[Illustration]
INTRODUCTION.
If we are struck with wonder and admiration at the progress of the arts
and manufactures, and have daily reason to congratulate ourselves on the
skill and ingenuity of our fellow-creatures, by which our comforts and
conveniences are so much increased; it must also occasionally have
crossed our minds, that some of the meaner creatures, though not gifted
with our reasoning powers, and therefore not able to profit by the
experience of the past, are yet employed in their several departments,
and according to their several wants, in exceedingly curious and useful
manufactures, mostly designed for the shelter and preservation of
themselves or their offspring, but serving, not unfrequently, a higher
purpose, in administering to the wants of mankind.
In reading the history, or in watching the proceedings of birds and
insects, how many remarkable instances do we meet with of that which may
be called _manufacture_, though performed without hands! How curious to
watch in the early spring the proceedings of those busy basket-making
birds, the rooks! Rude and clumsy as their nests may at first appear, it
is just the sort of workmanship best calculated for their wants. They do
not, indeed, choose the smooth and flexible osier-twigs which we should
think necessary for basket-making, but they contrive by means of
brittle, dead, forked sticks, to plait together a strong bristling
out-work, within which they interweave a finer basket-work of fibrous
roots, rude indeed, but not inelegant or unsuitable. Then, among birds
and insects too, what persevering and industrious carpenters, masons,
tailors, miners, and weavers may we not find. Perhaps there are not many
persons who have watched the mason-wasps boring their galleries in brick
or sand, or building the round towers which serve them as out-works; nor
the mason-bee, as she plasters together her neat mud-wall cottage or
cell, as the future habitation of her young; but there are few persons
unacquainted with the masonry of the chimney swallow, or of the
house-martin twittering on the eaves. With no other tools than those
which nature supplies, how cleverly do these creatures shape and mould
their nests into the required form, using for their work a mortar
carefully prepared by their own labour and skill, and just of the
consistency required. Few, again, may have had an opportunity of seeing
carpenter-bees boring holes in posts or palings, and forming their
smoothly chiselled cells, or of inspecting the partitioned galleries dug
out in old timber by carpenter-wasps; but perhaps many persons have
observed the colonies of emmets, or carpenter-ants, working in the
trunks of decaying oak or willow trees; or they may have listened to
that interesting carpenter-bird, the wood-pecker, tapping and boring
into trees, in pursuit of insects, and for the purpose of making a
nesting-place for its young. Most of us know only by hearsay that there
are tailor-birds, common enough in American orchards, who sew together
broad pieces of grass to make their nests, working them through and
through, as if actually done with a needle; but almost every one can say
from his own knowledge, that there are weaver-birds, such as our common
hedge-sparrow and chaffinch, who weave a circular piece of haircloth for
the interior of their nests, each hair being collected and interwoven
singly, and always bent so as to lie smoothly in the hollow of the nest.
Then who shall describe all the wondrous proceedings of tent-making
caterpillars, upholsterer-bees, turret-building ants, net-making
spiders, paper and card-making wasps, and spinning worms? Volumes have
been written, and volumes might still be written on the history of these
creatures. Any one possessing a garden, and taking delight therein, has
ample opportunity of watching the habits of birds and insects, and of
confirming, if not of adding to, the accounts given by naturalists, of
the commoner species. But we must still be indebted to the patient
observations of those who have made insects or birds their especial
study, for many of the most curious particulars, and for all our
knowledge of rare or foreign species.
Interesting as is the whole subject of bird and insect manufactures,
there is one department in which we are more concerned than the rest;
namely, that in which the product can be applied to our own use, either
in the way of food or clothing. Now this department is supplied wholly
by insects, no bird, that we are aware of, producing by its own
manufacturing powers, any substance that can be so employed, unless,
indeed, we except the curious edible nests of the Java swallow, which
have been converted by the taste of oriental epicures into an article of
food.
Let us then proceed to notice such of the insect manufactures as are
useful to man, and trace, at the same time, the history and performances
of these small but not insignificant manufacturers.
[Illustration: [Butterflies]]
CHAPTER I.
MANUFACTURE OF SILK BY CATERPILLARS OF VARIOUS KINDS.
The most important of all the insect manufactures is doubtless that of
silk-spinning. It seems almost past belief that the magnificent velvets,
satins, and silks which form so elegant a part of female attire, and
which are heaped together in such costly profusion in the shops of the
metropolis, and in those of all considerable towns, whether in our own,
or in foreign countries—that these splendid fabrics, together with all
ribbons, gauzes, damasks, or other articles composed of silk, should owe
the raw material of which they are formed to the labours of a race of
little creeping caterpillars, which in this their early and imperfect
state spin for themselves cocoons, or cases of silk, where they may
quietly undergo their changes until they become perfect winged insects.
[Illustration:
CATERPILLAR SUSPENDED BY ITS SILKEN THREAD.
]
The astonishing task of supplying silk for the whole civilized world is
performed almost without exception by the common silkworm, or
caterpillar of the mulberry-tree moth. But it must not be supposed that
this is the only silk-producing insect. On the contrary, all the
caterpillars of butterflies and moths have the power of spinning a
certain quantity of silken thread, however small, and however inferior
to that of the silkworm, properly so called. It is very common in
gardens to see numbers of caterpillars dangling by their silken threads
from the young branches of fruit-trees. In this way they let themselves
down, or break their fall if blown off by the wind, or otherwise shaken
from their favourite tree. And in the case of some caterpillars when the
insect has completed the term of its existence and becomes a chrysalis,
it suspends itself by silken cords to some fixed point, where it remains
in complete repose, without food, perhaps for months before the perfect
winged insect bursts forth, as different a creature from the caterpillar
as the chrysalis is from either,—and yet these are but three different
states of existence of the same insect.
[Illustration:
CHRYSALIS SUSPENDED BY SILKEN CORDS.
]
According to the particular species of caterpillar, the silk will vary
in strength and fineness, and also in colour, but seldom will it be
found strong enough, or in sufficient quantity to be of use to us. The
insects themselves employ it in many ways for their own safety and
shelter. How common it is to find some of the leaves of a lilac-tree
made up into little rolls, or folded together at their edges, where they
stick so fast that it requires some little force to pull them asunder.
This is the work of a small caterpillar, whose subsistence is found on
that tree. A single egg has been laid on each leaf selected by the
parent moth, and soon after it is hatched, the caterpillar begins
rolling up the lilac leaf, and fastening the edges with silk. This is a
work of time, but gradually proceeds as the caterpillar increases in
strength, until at last it is shut up in a gallery of its own making,
safe from the attacks of birds and larger insects. The leaves of various
other trees are rolled in a somewhat similar manner, as those of the
oak, the willow, and the rose, and also those of humbler plants, as the
plantain, nettle, thistle, &c. The mode in which these leaf-rolling
caterpillars set to work to form convenient habitations of the leaves of
the plants on which they feed, is well described by Kirby and Spence.
[Illustration:
OAK LEAF ROLLED BY A CATERPILLAR.
]
“Some of these merely connect together with a few silken threads several
leaves, so as to form an irregular packet, in the centre of which the
little hermit lives. Others confine themselves to a single leaf, of
which they simply fold one part over the other. A third description form
and inhabit a sort of roll, by some species made cylindrical, by others
conical, resembling the papers in which grocers put their sugar, and as
accurately constructed; only there is an opening left at the smaller
extremity for the egress of the insect in case of need. If you were to
see one of these rolls, you would immediately ask by what mechanism it
could possibly be made—how an insect, without fingers, could contrive to
bend a leaf into a roll, and to keep it in that form until fastened with
the silk which holds it together? The following is the operation: the
little caterpillar first fixes a series of silken cables from one side
of the leaf to the other: she next pulls at these cables with her feet;
and when she has forced the sides to approach, she fastens them together
with stronger threads of silk. If the insect finds that one of the
larger nerves of the leaf is so strong as to resist her efforts, she
weakens it by gnawing it here and there half through. What engineer
could act more sagaciously? To form one of the conical or horn-shaped
rolls, which are not composed of a whole leaf, but of a long triangular
portion cut out of the edge, some other manœuvres are requisite. Placing
herself upon the leaf, the caterpillar cuts out with her jaws the piece
which is to compose her roll. She does not, however, entirely detach it;
it would then want a base. She detaches that part only which is to form
the contour of the horn. This portion is a triangular strap, which she
rolls as she cuts. When the body of the horn is finished, as it is
intended to be fixed upon the leaf in nearly an upright position, it is
necessary to elevate it. To effect this, she proceeds as we should with
an inclined obelisk. She attaches threads, or little cables, towards the
point of the pyramid, and raises it by the weight of her body.”
Other larvæ form their habitations wholly of silk: one that inhabits the
leaves of pear-trees forms a little tent; another a sort of cloak;
another, as in the case of the silkworm, a complete ball of silk.
[Illustration:
PENDULOUS NESTS OF CATERPILLARS.
]
Among leaf-rolling caterpillars, one of the most curious is described by
Bonnet, in which the nest hangs suspended from the branch of a
fruit-tree by a strong silken thread. It is formed of one or two leaves
neatly folded and fastened together with silk, and in this small
enclosure several caterpillars live harmoniously together.
[Illustration:
LEAF CUTTING CATERPILLAR.
]
There is also a very curious and beautiful nest formed by a rare insect,
which has only yet been observed in its caterpillar state; but its
proceedings therein are interesting and highly remarkable. The length of
the body in this caterpillar varies from six to eight inches, the
thickness is half a line. The general colour is bluish green, tending to
yellow about the head; the feet are black, and six in number. At the
extremity of the body are two points projecting sideways. The eyes are
visible and prominent in this caterpillar, and besides the antennæ there
are two or three pairs of palpi or feelers, which perform the office of
hands. This insect inhabits the nut-tree, and cuts out from its leaves a
most ingenious case, which serves for its dwelling-place. This case is
of a singular form, being an elongated cone, very narrow at the
extremity, and tolerably wide at the orifice. It is formed of a strip of
nut-leaf, wound up in a spiral manner, but so cleverly contrived that
the strip is very narrow at the extremity, and gradually widens as the
work proceeds. This happens from the gradual progress of the work, which
is begun in the early stage of the caterpillar’s existence, when it does
not require a large dwelling-place, and becomes more and more extended
to suit the growth of its inmate. When it is completed, it is rather
more than an inch long, and two lines in diameter at the orifice. The
outside of the case presents the upper surface of the leaf in which the
indentations are preserved. The dwelling is a spacious one for the
caterpillar, so that it can turn round in it with perfect ease. The band
of which the cone is composed is taken from the edge of the leaf, which
the caterpillar cuts away in proportion as it winds it round its own
body. When one portion has taken the required form, a little more is cut
out, but always in a direction parallel with the edge of the leaf. While
the insect is thus gradually rolling itself up in a case, it also feeds
vigorously on the leaf, taking care, however, always to spare the band
which forms its habitation. Another part of the cleverness of this
insect consists in maintaining this strip of leaf in its spiral form,
which would otherwise naturally unwind by its own weight, and flutter in
the wind as a torn fragment. Here it is that silk is again skilfully
employed. The caterpillar commences much as other leaf-rolling insects
do, by fastening a thread to the edge of the leaf and drawing it towards
the desired point. But as the work proceeds the insect generally has
three skeins or bands of silk extended from the opening of its case to
the leaf. The first is the shortest and the most direct, issuing from
the interior of the roll; the second is fastened to the middle of the
last spiral, and extends to the leaf; the third is more extensive still,
and all three are admirably disposed for keeping the leaf bent to the
proper form. These skeins are composed of a great number of threads
parallel with each other, which not only serve to retain the leaf in its
spiral form, but also serve the caterpillar as a kind of ladder, by
which it mounts, and on which it rests while cutting out fresh portions
of leaf.
[Illustration:
LEAF-NEST UNWOUND.
]
It sometimes happens accidentally to this caterpillar that the case
becomes detached from the leaf, or naturalists have purposely severed a
portion to see what would be the result; but this does not greatly
disturb the insect, for as long as a single thread of silk remains to
hold the pieces together, the caterpillar is able to repair the evil. It
will unite the fractured portion almost imperceptibly by means of silken
threads, and proceed with its case as before; but if the leaf dry up and
wither, the insect is then compelled to desert it, and to select a
younger and fresher leaf for its operations.
What is still more curious, on the completion of the dwelling, the
caterpillar sometimes wishes to make an excursion to another part of the
leaf, and to take its house with it, and this it accomplishes in the
following manner. Coming more than three parts out of the cone, the
creature makes new skeins in advance of the old, and attempts to pull
the cone forward by their means; but finding that this does not succeed,
it bends its body back, and quickly severs the old threads and the
portion of leaf which keeps the case immovable. It is now able to draw
the case onwards a certain distance, after which it has only to repeat
the operation, and make other new skeins in advance of these, to
continue its onward journey. Thus it arrives at the opposite edge of the
leaf, where it carefully adjusts its case to the under side, fastening
it with great ingenuity, and drawing the threads tighter where the cone
is not properly balanced. In all these cases, silk is the useful
material by which the caterpillar secures its nest, and provides for its
own safety: it is also a constant resource in case of danger, or of
accident, as the following anecdote will show. A caterpillar of the
goat-moth, being confined in a smooth glass sugar-basin, managed to
crawl up the slippery sides and escape. This excited great surprise in
the naturalist (Rösel) who had imprisoned the creature, and he therefore
took occasion closely to watch its proceedings when again placed in a
similar vessel. It was with surprise and admiration that he now saw the
caterpillar constructing a silken ladder on the side of the glass; the
natural gum of the silk being sufficient to secure it even to that
perfectly smooth surface. Up this ladder the creature crawled, and thus
easily and expeditiously made its escape.
[Illustration:
SILKEN LADDER SPUN BY THE GOAT-MOTH CATERPILLAR.
]
Silkworms abound in our own country, as well as in others; but the silk
they spin is too fragile and scanty to be employed for other purposes
than their own. It is different with some of the caterpillars of India.
Although the great supply of silk is there obtained, as with us, from
the silkworm of the mulberry-tree, yet the caterpillars of various moths
also furnish a considerable quantity. The most important of these are
the _Tusseh_ and _Arindy_ silkworms, both natives of Bengal. The first
feeds on the leaves of the jujube tree and of the asseen, and is found
in such abundance as from time immemorial to have afforded a constant
supply of coarse, dark-coloured silk, which is woven into a cheap but
very durable cloth.
[Illustration:
THE TUSSEH SILKWORM.
]
When the caterpillars approach their full size they are too heavy to
crawl in search of their food with the back upwards, as is usual with
most caterpillars, but traverse the small branches suspended by the
feet, as is shown in the figure.
[Illustration:
COCOON OF THE TUSSEH SILKWORM.
]
When the caterpillar is ready to spin its cocoon, it connects by means
of the silk, (which is always glutinous when newly spun,) two or three
new leaves into an outer envelope, which serves as a basis to spin the
complete cocoon in, besides the cocoon being suspended from a branch of
the tree in a wonderful manner, by a thick, strong, consolidated cord,
spun of the same material by this persevering creature.
The cocoon is of an exact oval shape, and very firm in texture: in it
the animal remains dormant, and perfectly protected, for about nine
months, namely from October until July; so that it makes its appearance
in time for the caterpillars to come into existence, when Providence has
furnished them with the greatest plenty of proper food. When the insect
is prepared to make its escape and be changed into its perfect state, it
discharges from its mouth a large quantity of liquid, with which the
upper end of the case is so perfectly softened as to enable the moth to
work its way out in a very short time; an operation which is always
performed during the night. In their perfect state these insects do not
exist many days: the female deposits her eggs in the branches of the
tree she may be resting on, to which they adhere firmly by means of the
gluten they are covered with when newly laid.
The eggs are white, round, and compressed, with a depression in the
centre on each side. They hatch in from two to four weeks, according to
the state of the weather. The _larvæ_ or caterpillars acquire their full
size, which is about four inches in length, and three in circumference,
in about six weeks: they are nearly the colour of the leaves they feed
on, with a light yellowish stripe on each side; under these stripes the
middle segments are marked with an oblong gold-coloured speck. The back
is also marked with a few round darker coloured spots, from which issue
a few long, coarse, distinct hairs, while others of smaller size are
scattered over the insect.
The Tusseh silkworm is found in such abundance over many parts of Bengal
and the adjoining provinces, as to afford to the natives a large supply
of the durable, coarse, dark-coloured silk, already mentioned, commonly
called Tusseh silk, which is woven into a kind of cloth called Tusseh
doot’hies, much worn by Brahmins and other sects of Hindoos. This
substance would no doubt be highly useful to the inhabitants of many
parts of America and the south of Europe, where a cheap, light, cool,
durable dress, such as this silk makes, is much wanted. Millions of
cocoons of the Tusseh silkworm are annually collected in the jungle, and
brought to the silk factories near Calcutta. In other parts the people
gather and transplant them to the trees near their own dwellings, that
they may watch over the safety of the caterpillars, which are very
liable to be devoured by crows during the day time, and by bats at
night.
The Arindy silkworm feeds only on the leaves of the Palmi Christi; it
produces so delicate and flossy a silk that it cannot be wound from the
cocoons; it is therefore spun like cotton, and the thread woven into a
coarse kind of white cloth, of a loose texture, but so durable that a
person can scarcely in his lifetime wear out a garment made of it.
Eleven different species of silkworm have been enumerated as natives of
India, which has thus the internal means of providing the whole of
Europe with a material which would rival cotton and woollen cloth, and
would often be preferred to both, could it be obtained at a low price.
The produce of the Arindy silkworm, when sent to this country was much
admired, and some manufacturers to whom it was shown seemed to think
that they had been hitherto deceived in the account of the shawls of
India being made from the wool of a goat, and that this silk, if sent
home, could be made into shawls equal to any manufactured in India.
Many of the larvæ of the European moths afford a very strong silk, and
it is said, that a manufacture of silk from the cocoons of the emperor
moth was at one time established in Germany. There is no doubt, however,
that silk might be collected in abundance from many native silkworms in
America. Cocoons have been described eight inches long, made of grey
silk, which the inhabitants of Chilpancingo, Tixtala, and other places
in South America, manufacture into stockings and handkerchiefs. Humboldt
also observed similar nests in the provinces of Mechoacan, and the
mountains of Santa Rosa; they were of dense tissue, resembling Chinese
paper, of a brilliant whiteness, and formed of distinct and separate
layers. The interior layers, which are the thinnest, and of
extraordinary transparency, were used by the ancient Mexicans as writing
tablets.
[Illustration]