The Botanic Garden

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2. "HENCE orient NITRE owes it's sparkling birth,
And with prismatic crystals gems the earth,
145 O'er tottering domes in filmy foliage crawls,
Or frosts with branching plumes the mouldering walls.
As woos Azotic Gas the virgin Air,
And veils in crimson clouds the yielding Fair,
Indignant Fire the treacherous courtship flies,
150 Waves his light wing, and mingles with the skies.

[_Hence orient Nitre_. l. 143. Nitre is found in Bengal naturally
crystallized, and is swept by brooms from earths and stones, and thence
called sweepings of nitre. It has lately been found in large quantities
in a natural bason of calcareous earth at Molfetta in Italy, both in
thin strata between the calcareous beds, and in efflorescences of
various beautiful leafy and hairy forms. An account of this nitre-bed is
given by Mr. Zimmerman and abridged in Rozier's Journal de Physique
Fevrier. 1790. This acid appears to be produced in all situations where
animal and vegetable matters are compleatly decomposed, and which are
exposed to the action of the air as on the walls of stables, and
slaughter-houses; the crystals are prisms furrowed by longitudinal
groves.

Dr. Priestley discovered that nitrous air or gas which he obtained by
dissolving metals in nitrous acid, would combine rapidly with vital air,
and produce with it a true nitrous acid; forming red clouds during the
combination; the two airs occupy only the space before occupied by one
of them, and at the same time heat is given out from the new
combination. This dimunition of the bulk of a mixture of nitrous gas and
vital air, Dr. Priestley ingeniously used as a test of the purity of the
latter; a discovery of the greatest importance in the analysis of airs.

Mr. Cavendish has since demonstrated that two parts of vital air or
oxygene, and one part of phlogistic air or azote, being long exposed to
electric shocks, unite, and produce nitrous acid. Philos. Trans. Vols.
LXXV. and LXXVIII.

Azote is one of the most abundant elements in nature, and combined with
calorique or heat, it forms azotic gas or phlogistic air, and composes
two thirds of the atmosphere; and is one of the principal component
parts of animal bodies, and when united to vital air or oxygene produces
the nitrous acid. Mr. Lavoisier found that 211/2 parts by weight of
azote, and 431/2 parts of oxygene produced 64 parts of nitrous gas, and
by the further addition of 36 parts of oxygene nitrous acid was
produced. Traite de Chimie. When two airs become united so as to produce
an unelastic liquid much calorique or heat is of necessity expelled from
the new combination, though perhaps nitrous acid and oxygenated marine
acid admit more heat into their combinations than other acids.]

"So Beauty's GODDESS, warm with new desire,
Left, on her silver wheels, the GOD of Fire;
Her faithless charms to fiercer MARS resign'd,
Met with fond lips, with wanton arms intwin'd.
155 --Indignant VULCAN eyed the parting Fair,
And watch'd with jealous step the guilty pair;
O'er his broad neck a wiry net he flung,
Quick as he strode, the tinkling meshes rung;
Fine as the spider's flimsy thread He wove
160 The immortal toil to lime illicit love;
Steel were the knots, and steel the twisted thong,
Ring link'd in ring, indissolubly strong;
On viewless hooks along the fretted roof
He hung, unseen, the inextricable woof.--
165 --Quick start the springs, the webs pellucid spread,
And lock the embracing Lovers on their bed;
Fierce with loud taunts vindictive VULCAN springs,
Tries all the bolts, and tightens all the strings,
Shakes with incessant shouts the bright abodes,
170 Claps his rude hands, and calls the festive Gods.--
--With spreading palms the alarmed Goddess tries
To veil her beauties from celestial eyes,
Writhes her fair limbs, the slender ringlets strains,
And bids her Loves untie the obdurate chains;
175 Soft swells her panting bosom, as she turns,
And her flush'd cheek with brighter blushes burns.
Majestic grief the Queen of Heaven avows,
And chaste Minerva hides her helmed brows;
Attendant Nymphs with bashful eyes askance
180 Steal of intangled MARS a transient glance;
Surrounding Gods the circling nectar quaff,
Gaze on the Fair, and envy as they laugh.

3. "HENCE dusky IRON sleeps in dark abodes,
And ferny foliage nestles in the nodes;
185 Till with wide lungs the panting bellows blow,
And waked by fire the glittering torrents flow;
--Quick whirls the wheel, the ponderous hammer falls,
Loud anvils ring amid the trembling walls,
Strokes follow strokes, the sparkling ingot shines,
190 Flows the red slag, the lengthening bar refines;
Cold waves, immersed, the glowing mass congeal,
And turn to adamant the hissing Steel.

[_Hence dusky Iron_. l. 183. The production of iron from the
decomposition of vegetable bodies is perpetually presented to our view;
the waters oozing from all morasses are chalybeate, and deposit their
ochre on being exposed to the air, the iron acquiring a calciform state
from its union with oxygene or vital air. Where thin morasses lie on
beds of gravel the latter are generally stained by the filtration of
some of the chalybeate water through them. This formation of iron from
vegetable recrements is further evinced by the fern leaves and other
parts of vegetables, so frequently found in the centre of the knobs or
nodules of some iron-ores.

In some of these nodules there is a nucleus of whiter iron-earth
surrounded by many concentric strata of darker and lighter iron-earth
alternately. In one, which now lies before me, the nucleus is a prism of
a triangular form with blunted angles, and about half an inch high, and
an inch and half broad; on every side of this are concentric strata of
similar iron-earth alternately browner and less brown; each stratum is
about a tenth of an inch in thickness and there are ten of them in
number. To what known cause can this exactly regular distribution of so
many earthy strata of different colours surrounding the nucleus be
ascribed? I don't know that any mineralogists have attempted an
explanation of this wonderful phenomenon. I suspect it is owing to the
polarity of the central nucleus. If iron-filings be regularly laid on
paper by means of a small sieve, and a magnet be placed underneath, the
filings will dispose themselves in concentric curves with vacant
intervals between them. Now if these iron-filings are conceived to be
suspended in a fluid, whose specific gravity is similar to their own,
and a magnetic bar was introduced as an axis into this fluid, it is easy
to foresee that the iron filings would dispose themselves into
concentric spheres, with intervals of the circumnatant fluid between
them, exactly as is seen in these nodules of iron-earth. As all the
lavas consist of one fourth of iron, (Kirvan's Mineral) and almost all
other known bodies, whether of animal or vegetable origin, possess more
or less of this property, may not the distribution of a great portion of
the globe of the earth into strata of greater or less regularity be
owing to the polarity of the whole?]

[_And turn to adamant_. l. 192. The circumstances which render iron more
valuable to mankind than any other metal are, 1. its property of being
rendered hard to so great a degree and thus constituting such excellent
tools. It was the discovery of this property of iron, Mr. Locke thinks,
that gave such pre-eminence to the European world over the American one.
2. Its power of being welded; that is, when two pieces are made very hot
and applied together by hammering, they unite compleatly, unless any
scale of iron intervenes; and to prevent this it is usual for smiths to
dip the very hot bar in sand, a little of which fuses into fluid glass
with the scale and is squeezed out from between the uniting parts by the
force of hammering. 3. Its power of acquiring magnetism.

It is however to be wished that gold or silver were discovered in as
great quantity as iron, since these metals being indestructible by
exposure to air, water, fire or any common acids would supply wholesome
vessels for cookery, so much to be desired, and so difficult to obtain,
and would form the most light and durable coverings for houses, as well
as indestructible fire-grates, ovens, and boiling vessels. See
additional notes, No. XVIII. on Steel.]

"Last MICHELL'S hands with touch of potent charm
The polish'd rods with powers magnetic arm;
195 With points directed to the polar stars
In one long line extend the temper'd bars;
Then thrice and thrice with steady eye he guides,
And o'er the adhesive train the magnet slides;
The obedient Steel with living instinct moves,
200 And veers for ever to the pole it loves.

[_Last Michell's hands_. l. 193. The discovery of the magnet seems to
have been in very early times; it is mentioned by Plato, Lucretius,
Pliny, and Galen, and is said to have taken its name of magnes from
Magnesia, a sea-port of antient Lybia.

As every piece of iron which was made magnetical by the touch of a
magnet became itself a magnet, many attempts were made to improve these
artificial magnets, but without much success till Servingdon Savary,
Esq. made them of hardened steel bars, which were so powerful that one
of them weighing three pounds averdupois would lift another of the same
weight. Philos. Trans.

After this Dr. Knight made very successful experiments on this subject,
which, though he kept his method secret, seems to have excited others to
turn their attention to magnetism. At this time the Rev. Mr. Michell
invented an equally efficacious and more expeditious way of making
strong artificial magnets, which he published in the end of the year
1750, in which he explained his method of what he called "the double
touch", and which, since Mr. Knight's method has been known, appears to
be somewhat different from it.

This method of rendering bars of hardened steel magnetical consists in
holding vertically two or more magnetic bars nearly parallel to each
other with their opposite poles very near each other (but nevertheless
separated to a small distance), these are to be slided over a line of
bars laid horizontally a few times backward and forward. See Michell on
Magnetism, also a detailed account in Chamber's Dictionary.

What Mr. Michell proposed by this method was to include a very small
portion of the horizontal bars, intended to be made magnetical, between
the joint forces of two or more bars already magnetical, and by sliding
them from end to end every part of the line of bars became successively
included, and thus bars possessed of a very small degree of magnetism to
begin with, would in a few times sliding backwards and forwards make the
other ones much more magnetical than themselves, which are then to be
taken up and used to touch the former, which are in succession to be
laid down horizontally in a line.

There is still a great field remains for future discoveries in magnetism
both in respect to experiment and theory; the latter consists of vague
conjectures the more probable of which are perhaps those of Elpinus, as
they assimulate it to electricity.

One conjecture I shall add, viz. that the polarity of magnetism may be
owing to the earth's rotatory motion. If heat, electricity, and
magnetism are supposed to be fluids of different gravities, heat being
the heaviest of them, electricity the next heavy, and magnetism the
lightest, it is evident that by the quick revolution of the earth the
heat will be accumulated most over the line, electricity next beneath
this, and that the magnetism will be detruded to the poles and axis of
the earth, like the atmospheres of common air and of inflammable gas, as
explained in the note on Canto I. l. 123.

Electricity and heat will both of them displace magnetism, and this
shows that they may gravitate on each other; and hence when too great a
quantity of the electric fluid becomes accumulated at the poles by
descending snows, or other unknown causes, it may have a tendency to
rise towards the tropics by its centrifugal force, and produce the
northern lights. See additional notes, No. I.]

"Hail, adamantine STEEL! magnetic Lord!
King of the prow, the plowshare, and the sword!
True to the pole, by thee the pilot guides
His steady helm amid the struggling tides,
205 Braves with broad sail the immeasurable sea,
Cleaves the dark air, and asks no star but Thee.--
By thee the plowshare rends the matted plain,
Inhumes in level rows the living grain;
Intrusive forests quit the cultured ground,
210 And Ceres laughs with golden fillets crown'd.--
O'er restless realms when scowling Discord flings
Her snakes, and loud the din of battle rings;
Expiring Strength, and vanquish'd Courage feel
Thy arm resistless, adamantine STEEL!

215 4. "HENCE in fine streams diffusive ACIDS flow,
Or wing'd with fire o'er Earth's fair bosom blow;
Transmute to glittering Flints her chalky lands,
Or sink on Ocean's bed in countless Sands.
Hence silvery Selenite her chrystal moulds,
220 And soft Asbestus smooths his silky folds;
His cubic forms phosphoric Fluor prints,
Or rays in spheres his amethystine tints.
Soft cobweb clouds transparent Onyx spreads,
And playful Agates weave their colour'd threads;
225 Gay pictured Mochoes glow with landscape-dyes,
And changeful Opals roll their lucid eyes;
Blue lambent light around the Sapphire plays,
Bright Rubies blush, and living Diamonds blaze.

[_Diffusive Acids flow_. l. 215. The production of marine acid from
decomposing vegetable and animal matters with vital air, and of nitrous
acid from azote and vital air, the former of which is united to its
basis by means of the exhalations from vegetable and animal matters,
constitute an analogy which induces us to believe that many other acids
have either their bases or are united to vital air by means of some part
of decomposing vegetable and animal matters.

The great quantities of flint sand whether formed in mountains or in the
sea would appear to derive its acid from the new world, as it is found
above the strata of lime-stone and granite which constitute the old
world, and as the earthy basis of flint is probably calcareous, a great
part of it seems to be produced by a conjunction of the new and old
world; the recrements of air-breathing animals and vegetables probably
afford the acid, and the shells of marine animals the earthy basis,
while another part may have derived its calcareous part also from the
decomposition of vegetable and animal bodies.

The same mode of reasoning seems applicable to the siliceous stones
under various names, as amethyst, onyx, agate, mochoe, opal, &c. which
do not seem to have undergone any process from volcanic fires, and as
these stones only differ from flint by a greater or less admixture of
argillaceous and calcareous earths. The different proportions of which
in each kind of stone may be seen in Mr. Kirwan's valuable Elements of
Mineralogy. See additional notes, No. XIX.]

[_Living diamonds blaze_. l. 228. Sir Isaac Newton having observed the
great power of refracting light, which the diamond possesses above all
other crystallized or vitreous matter, conjectured that it was an
inflammable body in some manner congealed. Insomuch that all the light
is reflected which falls on any of its interior surfaces at a greater
angle of incidence than 241/2 degrees; whereas an artificial gem of
glass does not reflect any light from its hinder surface, unless that
surface is inclined in an angle of 41 degrees. Hence the diamond
reflects half as much more light as a factitious gem in similar
circumstances; to which must be added its great transparency, and the
excellent polish it is capable of. The diamond had nevertheless been
placed at the head of crystals or precious stones by the mineralogists,
till Bergman ranged it of late in the combustible class of bodies,
because by the focus of Villette's burning mirror it was evaporated by a
heat not much greater than will melt silver, and gave out light. Mr.
Hoepfner however thinks the dispersion of the diamond by this great heat
should be called a phosphorescent evaporation of it, rather than a
combustion; and from its other analogies of crystallization, hardness,
transparency, and place of its nativity, wishes again to replace it
amongst the precious stones. Observ. sur la Physique, par Rozier, Tom.
XXXV. p. 448. See new edition of the Translation of Cronsted, by De
Costa.]

"Thus, for attractive earth, inconstant JOVE
230 Mask'd in new shapes forsook his realms above.--
First her sweet eyes his Eagle-form beguiles,
And HEBE feeds him with ambrosial smiles;
Next the chang'd God a Cygnet's down assumes,
And playful LEDA smooths his glossy plumes;
235 Then glides a silver Serpent, treacherous guest!
And fair OLYMPIA folds him in her breast;
Now lows a milk-white Bull on Afric's strand,
And crops with dancing head the daisy'd land.--
With rosy wreathes EUROPA'S hand adorns
240 His fringed forehead, and his pearly horns;
Light on his back the sportive Damsel bounds,
And pleased he moves along the flowery grounds;
Bears with slow step his beauteous prize aloof,
Dips in the lucid flood his ivory hoof;
245 Then wets his velvet knees, and wading laves
His silky sides amid the dimpling waves.
While her fond train with beckoning hands deplore,
Strain their blue eyes, and shriek along the shore;
Beneath her robe she draws her snowy feet,
250 And, half-reclining on her ermine seat,
Round his raised neck her radiant arms she throws,
And rests her fair cheek on his curled brows;
Her yellow tresses wave on wanton gales,
And high in air her azure mantle sails.
255 --Onward He moves, applauding Cupids guide,
And skim on shooting wing the shining tide;
Emerging Triton's leave their coral caves,
Sound their loud conchs, and smooth the circling waves,
Surround the timorous Beauty, as she swims,
260 And gaze enamour'd on her silver limbs.
--Now Europe's shadowy shores with loud acclaim
Hail the fair fugitive, and shout her name;
Soft echoes warble, whispering forests nod,
And conscious Nature owns the present God.
265 --Changed from the Bull, the rapturous God assumes
Immortal youth, with glow celestial blooms,
With lenient words her virgin fears disarms,
And clasps the yielding Beauty in his arms;
Whence Kings and Heroes own illustrious birth,
270 Guards of mankind, and demigods on earth.

[_Inconstant Jove_. l. 229. The purer air or ether in the antient
mythology was represented by Jupiter, and the inferior air by Juno; and
the conjunction of these deities was said to produce the vernal showers,
and procreate all things, as is further spoken of in Canto III. l. 204.
It is now discovered that pure air, or oxygene, uniting with variety of
bases forms the various kinds of acids; as the vitriolic acid from pure
air and sulphur; the nitrous acid from pure air and phlogistic air, or
azote; and carbonic acid, (or fixed air,) from pure air and charcoal.
Some of these affinities were perhaps portrayed by the Magi of Egypt,
who were probably learned in chemistry, in their hieroglyphic pictures
before the invention of letters, by the loves of Jupiter with
terrestrial ladies. And thus physically as well as metaphysically might
be said "Jovis omnia plena."]

VI. "GNOMES! as you pass'd beneath the labouring soil,
The guards and guides of Nature's chemic toil,
YOU saw, deep-sepulchred in dusky realms,
Which Earth's rock-ribbed ponderous vault o'erwhelms,
275 With self-born fires the mass fermenting glow,
And flame-wing'd sulphurs quit the earths below.

[_With self-born fires_. l. 275. After the accumulation of plains and
mountains on the calcareous rocks or granite which had been previously
raised by volcanic fires, a second set of volcanic fires were produced
by the fermentation of this new mass, by which after the salts or acids
and iron had been washed away in part by elutriation, dissipated the
sulphurous parts which were insoluble in water; whence argillaceous and
siliceous earths were left in some places; in others, bitumen became
sublimed to the upper part of the stratum, producing coals of various
degrees of purity.]

1. "HENCE ductile CLAYS in wide expansion spread,
Soft as the Cygnet's down, their snow-white bed;
With yielding flakes successive forms reveal,
280 And change obedient to the whirling wheel.
--First CHINA'S sons, with early art elate,
Form'd the gay tea-pot, and the pictured plate;
Saw with illumin'd brow and dazzled eyes
In the red stove vitrescent colours rise;
285 Speck'd her tall beakers with enamel'd stars,
Her monster-josses, and gigantic jars;
Smear'd her huge dragons with metallic hues,
With golden purples, and cobaltic blues;
Bade on wide hills her porcelain castles glare,
290 And glazed Pagodas tremble in the air.

[_Hence ductile clays_ l. 277. See additional notes, No. XX.]

[_Saw with illumin'd brow_. l. 283. No colour is distinguishable in the
red-hot kiln but the red itself, till the workman introduces a small
piece of dry wood, which by producing a white flame renders all the
other colours visible in a moment.]

[_With golden purples_. l. 288. See additional notes, No. XXI.]

"ETRURIA! next beneath thy magic hands
Glides the quick wheel, the plaistic clay expands,
Nerved with fine touch, thy fingers (as it turns)
Mark the nice bounds of vases, ewers, and urns;
295 Round each fair form in lines immortal trace
Uncopied Beauty, and ideal Grace.

[_Etruria! next_. l. 291. Etruria may perhaps vie with China itself in
the antiquity of its arts. The times of its greatest splendour were
prior to the foundations of Rome, and the reign of one of its best
princes, Janus, was the oldest epoch the Romans knew. The earliest
historians speak of the Etruscans as being then of high antiquity, most
probably a colony from Phoenicia, to which a Pelasgian colony acceded,
and was united soon after Deucalion's flood. The peculiar character of
their earthern vases consists in the admirable beauty, simplicity, and
diversity of forms, which continue the best models of taste to the
artists of the present times; and in a species of non-vitreous encaustic
painting, which was reckoned, even in the time of Pliny, among the lost
arts of antiquity, but which has lately been recovered by the ingenuity
and industry of Mr. Wedgwood. It is supposed that the principal
manufactories were about Nola, at the foot of Vesuvius; for it is in
that neighbourhood that the greatest quantities of antique vases have
been found; and it is said that the general taste of the inhabitants is
apparently influenced by them; insomuch that strangers coming to Naples,
are commonly struck with the diversity and elegance even of the most
ordinary vases for common uses. See D'Hancarville's preliminary
discourses to the magnificent collection of Etruscan vases, published by
Sir William Hamilton.]

"GNOMES! as you now dissect with hammers fine
The granite-rock, the nodul'd flint calcine;
Grind with strong arm, the circling chertz betwixt,
300 Your pure Ka-o-lins and Pe-tun-tses mixt;
O'er each red saggars burning cave preside,
The keen-eyed Fire-Nymphs blazing by your side;
And pleased on WEDGWOOD ray your partial smile,
A new Etruria decks Britannia's isle.--
305 Charm'd by your touch, the flint liquescent pours
Through finer sieves, and falls in whiter showers;
Charm'd by your touch, the kneaded clay refines,
The biscuit hardens, the enamel shines;
Each nicer mould a softer feature drinks,
310 The bold Cameo speaks, the soft Intaglio thinks.

[Illustration: _H. Webber init J. Holloway sculpt Copied from Capt.
Phillip's Voyage to Botany Bay, by permission of the Proprietor_]

[Transcriber's note: names of painter and engraver are only guesswork.]

[Illustration: AM I NOT A MAN AND A BROTHER]

"To call the pearly drops from Pity's eye,
Or stay Despair's disanimating sigh,
Whether, O Friend of art! the gem you mould
Rich with new taste, with antient virtue bold;
315 Form the poor fetter'd SLAVE on bended knee
From Britain's sons imploring to be free;
Or with fair HOPE the brightening scenes improve,
And cheer the dreary wastes at Sydney-cove;
Or bid Mortality rejoice and mourn
320 O'er the fine forms on PORTLAND'S mystic urn.--

[_Form the poor fetter'd Slave_. l. 315. Alluding to two cameos of Mr.
Wedgwood's manufacture; one of a Slave in chains, of which he
distributed many hundreds, to excite the humane to attend to and to
assist in the abolition of the detestable traffic in human creatures;
and the other a cameo of Hope attended by Peace, and Art, and Labour;
which was made of clay from Botany Bay; to which place he sent many of
them to shew the inhabitants what their materials would do, and to
encourage their industry. A print of this latter medallion is prefixed
to Mr. Stockdale's edition of Philip's Expedition to Botany Bay.]

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