Chapter III: Vegetables

Having thus enumerated a considerable variety of articles in the animal and fossile kingdoms, the only part which remains to be noticed is that of vegetables. To any person possessing but a superficial knowledge of botany, it must be obvious that this branch of natural history is extensive in the extreme; and that, consequently, to point out but a small number of such plants as form interesting objects for the microscope, would greatly extend this list, already sufficiently large; for,

“How incompetent is human effort to portray the beauties of this sublime subject! How inadequate the most descriptive talent to approximate to our view the vegetative profusion contained within the recess of nature! How limited have been our public researches! How contracted the knowledge which has been as yet obtained! What an incomprehensible store remains yet concealed, impenetrable to mortal view!”[171]

[171] Observations on the Structure and Economy of Plants, by R.
Hooper, M. D., F. L. S. page 128. This work contains an ingenious
display of the analogy which subsists between the animal and the
vegetable kingdom.

From a source so abundant, the botanist will be under no difficulty in selecting for himself; those who have not made the science a part of their studies, will be materially assisted by having recource to the elegant figures and their descriptions in the Botanical Magazine, by W. Curtis, F. L. S. the well-known author of Flora Londinensis; and English Botany, by J. E. Smith, M. D. F. R. & Pres. L. S. published by Ja^{s}. Sowerby, F. L. S. I shall, therefore, just mention in general terms those parts of plants which are peculiarly adapted for microscopical investigation. These are as follow:

The trunk, composed of
Epidermis or cuticle
Cortex or outer bark
Liber or inner bark
Alburnum
Lignum or wood
Medulla or pith
The root cut transversely or longitudinally
Leaves and their fibres
The parts of fructification, consisting of
The calyx or flower cup
corolla or foliation, containing the leaves or petals, and the
nectarium
stamina or threads, their filaments and anthera or summit, and the
pollen contained therein[172]
The pistillum or pointal, its germen, style, and stigma
pericarpium, seed vessel, or germen grown to maturity
semina, seeds and their parts
receptaculum, the base on which the fructification is seated

[172] The pollen or meal is a fine dust designed for the impregnation
of the germen; a small quantity of this meal being put into hot water
and applied to the microscope, will exhibit the bursting of the
elastic covering of each grain; and the escape of the smaller atoms,
which is the true farina.

Of the various classes of plants, that called cryptogamia is eminently calculated for microscopical observation; comprizing the filices, the musci, the algæ, and the fungi. On these subjects Hedwig has produced a valuable work, entitled Theoria Generationis et Fructificationis de Plantarum Cryptogamicarum, of which a new and much improved edition has just appeared, and to which for further information I refer the reader.

A LIST OF MR. CUSTANCE’S VEGETABLE CUTTINGS, THAT USUALLY ACCOMPANY THE MOST COMPLETE SORT OF MICROSCOPES MADE BY MESSRS. W. AND S. JONES.

English oak.
Evergreen ditto.
Norway oak.
Ash.
Cedar.
Cork.
Savin.
Fir.
Ceanothus.
Hazel.
Lime.
Elm.
Elm root.
Mulberry ditto.
Grape root.
Lime ditto.
Beech.
Birch.
Plum.
Ivy.
Spanish elder.
American climber.
Cissampelos.
Virgin’s bower.
Magnolia grandiflora.
Gelder-rose.
Althæa frutex.
Tulip tree.
Ash.
Spanish chesnut.
Platanus orientalis.
Viburnum lantana.
Oak root.
Ash root.
Asp root.
Walnut ditto.
Grape vine.
Indian turpeth.
China root.
Jasmine.
Dog rose.
Raspberry.
Barberry.
Briar.
Elder root.
Ditto branch.
Willow root.
Ditto branch.
Mulberry.
Fig.
Sycamore.
Maple.
American dogwood.
Ptelea trifoliata.
Ligneous night-shade.
Sumach.
Apricot.
Medlar.
Bay.
Laurel.
Sea weed.
Longitudinal cutting of plane tree.
Ditto of Spanish elder.
Ditto of briar.
Common cane.
Ditto with curious center.
Bamboo cane.
Sarsaparilla.
Longitudinal cuttings of sugar cane.
Elder.
Rose tree.
Mugwort.
*Longitudinal slices of elder.
*Ditto grape vine.
*Transverse ditto.
*Dogwood.
*Plane tree.
*Beech.
*Grape vine.
*Spanish chesnut.
*Walnut.
*Fig.
*Ditto longitudinal.
Asparagus.
Artichoke.
Thistle.
Fennel.
Parsley.
Ditto root.
Sunflower.
Ditto root.
Agrimony.
Eryngo.
Potatoe stalk.
Centaurea.
Indian reed.
Ditto corn.
Amaranthus.
Bromelia pinguin.
Campanula.
Monkshood.
Lavatera.
Solidago.
Mugwort.
Chrysanthemum.
Helianthus.
Wormwood.
Bulrush.
Portugal reed.
Burdock.
Ditto.
Wild mustard.
Aloe flower stalk.
Solomon’s seal.
Tulip.
Calamus aromaticus.
Buckbean.
Gourd.
Melon.
Crown imperial.
Flower-de-luce.
Pine apple.
White lily.
Asparagus.
Ragwort.
Water flag.
Sugar cane.
Stems of leaves of hog’s fennel.
Hemlock.
Chesnut.
Wild turnip.
Stems of the leaves of red dock.
Horse-radish.
Cabbage.
Carrots.
Roots of phytolacca.
Teasel.
Carrot.
Fennel.
Stinging-nettle roots curiously variegated.
Roots of parsley and wormwood variegated.
Stalks of fern, with variations.

N. B. Those marked with an * Mr. Custance conceives prove Dr. Hill in an error, when he observed, that the pith of a shoot is not connected with the pith of the branch. See his Construction of Timber, &c. p. 103, 8vo edition.

SALTS, AND VARIOUS CHEMICAL PREPARATIONS.

SALTS.

Salt ammoniac, crude
Salt ammoniac, volatile
Salt of amber
Salt of Benjamin, commonly called flowers of Benjamin
Salt of berberry
Salt of buckthorn
Salt of butcher’s broom
Salt of carduus
Salt of chamomile
Salt of coral
Salt of cucumber
Salt, Epsom, so called
Salt of fennel
Salt gem
Salt, glauber’s, vitriolated natron
Salt of hartshorn
Salt of lavender
Salt of lead, commonly called sugar of lead
Salt of limons
Salt of liquorice
Salt of millepedes
Salt of mugwort
Salt of nitre, or salt petre
Salt of Peruvian bark
Salt polychrest
Salt Rochelle
Salt of tartar
Salt of tartar vitriolated
Salt of tobacco
Salt of urine
Salt of wood sorrel
Salt of wormwood, and a great variety of others.[173]

[173] To ascertain the true configurations of salts, particular
attention should be paid to obtain them genuine; it may therefore be
proper to apprize the reader, that some of those above enumerated are
not easily procured in that state; consequently, though they exhibit
pleasing figures, yet they may not be those of the real salt purposed
to be investigated. Many hundred weights of some salts are annually
manufactured, and sold under names very different from what they
really are. Nor is this circumstance confined to salts only: for want
of botanical knowledge, preparations of different plants have been
frequently sold possessed of medical properties very different from
those intended. A valuable medicine, the extract of Hemlock, for
instance, instead of being prepared of the conium maculatum, has been
made in large quantities of the chærophyllum sylvestre, and thus
administered! On this unpleasant subject I could enlarge, were it not
digressing from that before us. Whilst such evils exist, need we
wonder if the physician as well as the patient are often disappointed
in the beneficial effects expected from the adhibition of medicines?

PREPARATIONS OF MERCURY.

Acetated quicksilver
Calcined ditto
Calomel
Muriat, commonly called corrosive sublimate
Red nitrated, or red precipitate
Sulphurated, or factitious cinnabar

MISCELLANEOUS.

Camphor
Crystals (called cream) of tartar
Iron, ammoniacal, or martial flowers
Verdigrise, ditto distilled
Vitriol, blue, or vitriolated copper
Vitriol, green, or vitriolated Iron
Vitriol, white, or vitriolated zinc, &c. &c.

After having particularized so many of the works of NATURE, let us now pay some attention to those of ART. But what an humiliating contrast shall we meet with! If our design in viewing objects by the microscope be to discover beauty, harmony, and perfection, it will be necessary to limit our inquiries to the former, happily alone sufficiently abundant; if, on the contrary, we are desirous of discovering deformity and imperfection, we must confine ourselves to the latter. Even those works of art that appear to the unassisted eye as decisive proofs of consummate skill in the workman, and which excite our admiration for their apparent neatness and accuracy, when brought to this test, exhibit their real state; and, consequently, tend but to display the inferiority of the most finished performance of the ablest artist, when put in competition with the glorious productions of nature. The finest works of the loom and of the needle, if exhibited with the microscope, prove so rude and coarse, that were they to appear thus to the naked eye, so far from affording delight to our belles, would be rejected with disgust. But the more we inquire into the works of nature, the more fully are we satisfied of their divine origin: in a flower, for instance, we see how fibres too minute for the unassisted sight are composed of others still more minute, till the primordial threads or first principles are utterly indiscernible; whilst the whole substance presents a celestial radiance in its colouring, with a richness so superior to silver or gold, as if it were intended for the cloathing of an angel, and we have the highest authority for asserting, that the greatest monarch of the East in all his glory, was not arrayed like one of these. A very few specimens of art will, therefore, suffice.

The edge of the sharpest razor or penknife
Teeth of rasps and files
Threads of the finest screws
Finest engravings on gold, silver, copper, &c.
Coins, medals
Seals, intaglios
Best executed miniature paintings, prints, drawings, &c.
The finest laces, silks, and ribbons
Smallest needles, pins, &c.
Woolen and linen cloth, plain or printed; camblets, bombazeens, &c.
A drop of ink on paper
Paper, from the coarsest to the finest
The writing of the ablest penman
The finest specimens of the typographic art, &c. &c.

An inspection of a few of the above articles only will clearly demonstrate, that as in the moral and political world, so in the works of art, perfection is unattainable by mortal man. With the fullest impression of which truth in the mind of the editor, and an appeal to the candour of his readers towards those imperfections which they may have discovered in this performance, he shall now conclude with,

FINIS.

ADDITIONS.

The following is a new, useful, and ready method of making globules for microscopes, differing from the customary one described in page 8, and is extracted from Mr. W. Nicholson’s scientifical Journal of Natural Philosophy, Chemistry, and the Arts. No. 3, June 1, 1797. p. 134.

“The usual method has been to draw out a fine thread of the soft white glass called crystal, and to convert the extremity of this into a spherule by melting it at the flame of a candle. But this glass contains lead, which is disposed to become opake by partial reduction, unless the management be very carefully attended to. I find that the hard glass used for windows seldom fails to afford excellent spherules. This glass is of a clear bright green colour when seen edgeways. A thin piece was cut from the edge of a pane of glass less than one-tenth of an inch broad. This was held perpendicularly by the upper end, and the flame of a candle was directed upon it by the blow-pipe at the distance of about an inch from the lower end. The glass became soft, and the lower piece descended by its own weight to the distance of about two feet, where it remained suspended by a thin thread of glass about one five-hundredth of an inch in diameter. A part of this thread was applied endways to the lower blue part of the flame of the candle without the use of the blow-pipe. The extremity immediately became white-hot, and formed a globule. The glass was then gradually and regularly thrust towards the flame, but never into it, until the globule was sufficiently large. A number of these were made, and being afterwards examined by viewing their focal images with a deeper magnifier, proved very bright, perfect, and round.”

* * * * *

The opake solar microscope has been made by the late Mr. Martin of larger dimensions than described in page 106. The illuminating lens, at A B, Plate V. Fig. 1, and the breadth of the mirror were about four inches and an half, instead of three inches, which gives more than double the light of the former; and, consequently, all the larger sort of opake and transparent objects, to the size of one and an half or two inches in diameter, as well as diverting objects painted on glass, like the magic lanthorn sliders, are shewn with the greatest distinctness, and has by Mr. Martin been called the MEGALASCOPE of the apparatus.

The same ingenious and learned artist applied a lattice of small squares about one-tenth of an inch, each square made of fine wire, or lines drawn strongly on glass in a circle of one inch in diameter, and placed these in the compound body of a microscope or telescope, in the focus of the glasses next to the eye. And having a copper-plate lattice of squares disposed into a circle, and to any size as may be wanted, the observer or artist may then with great facility make an exact drawing on the paper of the object observed. The same contrivance is applicable to the solar microscope. This he called the GRAPHICAL MICROSCOPE OR PERSPECTIVE.

Page 127, line 24--Any pocket telescope, the drawers of which are made to allow of a further extension than usual, may be used as a compound microscope for examining birds or insects alive, in a garden on the flowers, shrubberies, &c. from a window near to the objects. There are few pocket achromatic telescopes or perspectives, but what will define and magnify objects from about six feet to any distance from the instrument. The magnifying power is inversely as the distance of the object from the telescope, and, consequently variable in an infinite degree; on which account Mr. Martin named it the POLYDYNAMIC MICROSCOPE.

LIST OF THE PRICES

AT WHICH THE MICROSCOPES AND APPARATUS ARE MADE AND SOLD BY MESSRS. JONES, HOLBORN, LONDON.

Plate VIII. Fig. 8. A triple magnifier, tortoise-shell and
silver 1 1 0

---- 7. A ditto to combine, in tortoise-shell 0 8 0

VI. 14. A small pocket microscope for insects or
flowers 0 7 6

---- 1. Dr. Withering’s pocket botanical
microscope 0 15 0

---- 2. Jones’s universal pocket microscope,
according to the apparatus, from 1l. 6s.
to 2 10 0

II. B. 1 and 2. Wilson’s screw-barrel, or single
microscope, 2l. 12s. 6d. to 3 13 6

---- 3 and 4. ---- opake microscope, 2 2 0

VII. B. 3. Ellis’s aquatic microscope 2 12 6

VI. 3. Lyonet’s anatomical microscope 2 12 6