The Aquarium (Gosse)/Chapter 1
THE AQUARIUM.
CHAPTER I.
April is come at last. The arctic frosts, dreadful and protracted as they were, of February and March, that chilled the very life out of my poor cherished Actinias, and left me mourning over empty vases, have at last passed away, and here are the sweet, soft, south-west breezes of April. And now farewell to grimy, smoky London, and down, down, to Dorsetshire, as swiftly as the panting engine can drag us.
What a change have twenty four hours made! We raise the blind from our bed-room window, and instead of a forest of chimneys in the distance, and a mews in the foreground, with grooms currying horses that won't stand still, we gaze out upon the magnificent Bay of Weymouth, for our lodgings are on the ridge that they call the Lookout, with the sea below us breaking at the foot of the cliff.
The expanse before us has been described as second only to the beautiful Bay of Naples, by those who have seen both. I have not, and therefore cannot vouch for the justice of the comparison, but certainly this is a glorious prospect. It is a lovely morning; the sun has not long been up, but his effulgence fills the sky with splendour immediately in front, a splendour which trails along the intervening sea, as if it were the fiery monarch's train.[1] Away on the left stretch the bold promontories and abrupt cliffs of Purbeck, twenty miles of purple coast, gradually lessening in apparent height and in distinctness of outline, until the bluff precipice that terminates the line, St. Aldhelm's Head, is lost in the brightness of the eastern horizon. Then the broad expanse of boundless sea brings the eye to Portland on the right, a lofty rounded mass, thrown out into strong light by the opposite sunbeams, and to that noble work the Breakwater, as noble in design and object, as marvellous in execution, which perpetually creeps out into the domain of the sea, presenting an effectual though scarcely visible wall to the waves, until by and by it shall stretch halfway across our present field of view, and inclose a safe harbour of refuge, on which many a mariner will bestow his grateful blessing. At such a time as this sweet April morning, indeed, a work like this may seem of little value, when the waves of the ocean only just suffice to break its face into gems of changing brilliance, and to make whispering music; while vessels of all sizes, like those whose clustering masts we see yonder under the promontory, ride with perfect security in the open road. But in the fierce gales of November or March, when the shrieking blasts drive furiously up the Channel, and the huge mountain-billows, green and white, open threatening graves on every side, how welcome would be a safe harbour, easy of access, and placed at a part of the coast, which else would be unsheltered for many leagues on either side! Blessed be God for the gift of his beloved Son, the only Harbour of Refuge for poor tempest-tossed sinners! We may think lightly of it now, but in the coming day of gloom and wrath, when "the rain descends, and the floods come, and the winds blow," they only will escape who are sheltered there!
This visit to Weymouth was immediately connected with the Marine Aquarium. Those of my readers who have honoured my 'Rambles on the Devonshire Coast' with their perusal, may remember the experiments I have there recorded, on the making of such an invention practicable in London, and other inland towns, and my anticipations of success. Early in December, 1852, I put myself into communication with the Secretary of the Zoological Society, and the result was the transfer of a small collection of Zoophytes and Annelides, which I had brought up from Ilfracombe, and which I had kept for two months in vases in London,—to one of the tanks in the new Fish House just erected in the Society's Gardens in the Regent's Park. This little collection thus became the nucleus and the commencement of the Marine Aquarium afterwards exhibited there.
It was in consequence of an engagement to supply with marine inhabitants the other tanks which the Zoological Society proposed to devote to this object that I proceeded again to the coast. The prosecution of that employment during the months of May, June, and July, in the course of which upwards of five thousand specimens of animals and plants passed through my hands, made me acquainted with many curious facts in their economy and habits, and with many interesting traits in their history, which are not recorded (so far as I am aware) in works of science.
The facilities for observation thus afforded me have been augmented by means of Aquaria of various forms and sizes, which I have had made for my own private use, and of which I shall have occasion to speak in the following pages. In them I could mark with leisure and precision the manners of the creatures that were living at home, yet constantly under my eye.
Considering the novelty and curiosity of the exhibition thus offered to the public, and the popularity which it achieved, it may not be uninteresting to treat of a few of the more prominent objects in detail, and of the modes in which they were collected. We generally feel an interest in knowing somewhat of the antecedents of any person or thing that strongly attracts our attention; and in the present case more than idle curiosity may be gratified, since the record of my experiences may be useful to others in forming similar collections, either for public exhibition or for private study.
The idea of maintaining the balance between animal and vegetable life on chemical principles is not quite so novel as I had at first supposed. Priestley first advanced the opinion that plants in certain circumstances emitted oxygen gas; and Ingenhousz soon after discovered that the leaves of plants, when immersed in water, and exposed to the light of day, produced an air, which he announced as oxygen gas. This result, however, was doubted by Ellis, in his elaborate treatise on Atmospheric Air, and, as he considered, disproved.[2] The consumption of oxygen by animals in respiration, and the emission of carbonic acid from the lungs and skin, were well shown by this writer, who maintained, however, that this latter gas was also emitted by the leaves of plants.[3]
At the third Meeting of the British Association, held at Cambridge in 1833, Professor Daubeny communicated a notice of certain researches which he was then pursuing, concerning the action of light upon plants, and that of plants upon the atmosphere. "He considered that he had established, by experiments on plants immersed, sometimes in water impregnated with carbonic acid gas, and at others in atmospheric air containing a notable proportion of the same, that the action of light in promoting the discharge of certain of their functions, and especially that of the decomposition of carbonic acid, is dependent neither upon the heating, nor yet upon the chemical energy of the several rays, but upon their illuminating power.
"He regarded light as operating upon the green parts of plants as a specific stimulus, calling into action, and keeping alive those functions, from which the assimilation of carbon and the evolution of oxygen result. . . . .
"He had satisfied himself that in fine weather a plant consisting chiefly of leaves and stem will, if confined in the same portion of air night and day, and duly supplied with carbonic acid during the sunshine, go on adding to the proportion of oxygen present, so long as it continues healthy, at least up to a certain point. . . . .
"Considering the quantity of oxygen generated by a very small portion of a tree or shrub introduced, he saw no reasons to doubt that the influence of the vegetable might serve as a complete compensation for that of the animal kingdom."
In 1837, Mr. Ward made a Report to the British Association, "On the growth of Plants in closed Cases," at the end of which he "directed the attention of the members to the development of animal life upon the same principles." He was "quite certain that a great number of animals would live and thrive under this treatment."
In his treatise on the same subject, published in 1842, he dilates a little on this matter, chiefly with regard to increasing the purity of air for breathing in large towns, as a remedy for disease. "The difficulty to be overcome," he observes, "would be the removal or neutralization of the carbonic acid given out by animals; but this in the present state of science could easily be effected, either by ventilators or by the growth of plants in connexion with the air of the room, so that the animal and vegetable respirations might counterbalance each other. The volume of the air, with the quantity of vegetable matter required, as compared with the size and rank in creation of the animal, would be a problem well worthy of solution."[4]
In the same year (1842) Dr. Johnston published his "History of British Sponges and Lithophytes," in which, arguing out the vegetability of the latter, he mentioned in a note what is the most germane of all to our purpose,—the actual formation of a little Marine Aquarium. To Dr. Johnston therefore, as I think, must be assigned the honour of the first accomplishment of this object. His words are as follows:—
"Was there a need of adding any additional proof of the vegetability of the Corallines, an experiment now before me would seem to supply it. It is now eight weeks ago since I placed in a small glass jar, containing about six ounces of pure sea-water a tuft of the living Corallina officinalis, to which were attached two or three minute Confervæ, and the very young frond of a green Ulva; while numerous Rissoæ, several little Mussels and Annelides, and a Star-fish were crawling amid the branches. The jar was placed on a table, and was seldom disturbed, though occasionally looked at; and at the end of four weeks, the water was found to be still pure, the Mollusca and other animals all alive and active, the confervæ had grown perceptibly, and the coralline itself had thrown out some new shoots, and several additional articulations. Eight weeks have now elapsed since the experiment was begun,—the water has remained unchanged,—yet the coralline is growing, and apparently has lost none of its vitality; but the animals have sensibly decreased in numbers, though many of them continue to be active, and shew no dislike to their situation. What can be more conclusive? I need not say that if any animal, or even a sponge, had been so confined, the water would long before this time have been deprived of its oxygen, would have become corrupt and ammoniacal, and poisonous to the life of every living thing."[5]
On the 4th of March, 1850, at a Meeting of the Chemical Society, Mr. Robert Warington communicated the results of an experiment which he had been prosecuting for nearly a year, "On the adjustment of the relations between the animal and vegetable kingdoms, by which the vital functions of both are permanently maintained." Two small gold fish were placed in a glass receiver of about twelve gallons' capacity, covered with thin muslin to exclude dust and soot. The vessel was half filled with spring-water, with a bottom of sand and mud, and some loose fragments of limestone and sandstone, so arranged as to afford shelter and shade. A small specimen of Valisneria spiralis was at the same time planted in the mud, and kept in place by a stone. The whole was then left undisturbed.
Every thing went on well for a time, till it was found that the natural decay of the older leaves of the plant began to produce turbidity in the water, and a confervoid growth accumalated on the sides of the vessel, and on the surface of the water. To meet this emergency, Mr. Warington introduced a few common Pond-snails (Limnea), which greedily fed on the decaying vegetable matter and slimy mucous growth, so as quickly to restore the whole to a healthy state.
The result was now quite satisfactory. The plant throve and increased greatly by offshoots and suckers; the fishes continued to preserve their health and beauty, while the snails deposited enormous masses of eggs, thus supplying food for the fishes, as well as performing the office of scavengers.
Thus the success of the experiment was established, and an Aquarium was formed in fresh water; which has continued to prosper to the present time; the animals and plants maintaining each other in healthy life, and the water preserving its purity unchanged.
In January, 1852, Mr. Warington began to prosecute experiments of the same kind with sea-water, which presented some difficulties arising from the compound nature of that fluid, and from the peculiarities of marine vegetation. These difficulties, however, yielded to the perseverance and skill of the operator, and while I write these lines I am personal witness to his complete success, having just seen (January 1854) specimens of Sea-anemones and other marine animals in good health in that gentleman's Aquarium, which I know were sent from the sea-side more than a year and a quarter ago.
A Memoir by Mr. Warington, which appeared in the "Annals of Natural History" for November, 1853, gives some very interesting details of the progress of the marine experiments; and from it I shall make a few extracts.
"The sea-water with which the experiments were conducted, was obtained through the medium of one of the oyster-boats at the Billingsgate fish-market, and was taken from the middle of the English Channel.
"My first object was to ascertain the kind of seaweed best fitted, under ordinary circumstances, for keeping the water clear and sweet, and in a sufficiently oxygenated state to sustain animal life. And here opinions were at variance, for one naturalist friend whom I consulted, advised me to employ the Rhodosperms; another stated that it was impossible to make the red weeds answer the purpose, as he had tried them, and strongly recommended the olive or brown-coloured Algæ; while, again, others thought that I should be more successful with those which had in theory first suggested themselves to my own mind, namely the Chlorosperms. After making numerous unsuccessful experiments with both the brown and the red varieties of Algæ, I was fully convinced that the green weeds were the best adapted for the purpose.
"This point having been practically ascertained, and some good pieces of the Enteromorpha and Ulva latissima in a healthy state, attached to nodules of flint or chalk, having been procured from the shore near Broadstairs, several living animal subjects were introduced, together with the periwinkle. Everthing progressed satisfactorily, and these all continued in a healthy and lively condition.
"My first trials were conducted in one of the small tanks which had been used for fresh water; but as it was necessary, during the unsuccessful experiments with the brown and red sea-weeds, to agitate and aërate the water, which had been rendered foul from the quantity of mucus or gelatinous matter generated during the decay of their fronds, until the whole had become oxydized, and the water rendered clear and fitted for another experiment, it was, therefore, for greater convenience, removed into a shallow earthen pan, and covered with a large glass shade to protect the surface of the water, as much as possible, from the dust and soot of the London atmosphere, and at the same time impede the evaporation. In this vessel then I had succeeded perfectly in keeping a large number of beautiful living specimens in a healthy condition up to the close of 1852. I therefore gave instructions for the making of a small tank as a more permanent reservoir, and one more adapted for carrying on my observations and investigations on the economy and habits of the inhabitants.
"From the experience I had obtained in my experiments with the fresh-water tank, I was induced to modify slightly the construction of this vessel; thus, at the back, or part towards the light, the framing was filled with slate in the same way as the ends and bottom; for I had found that the glass, originally employed, very soon became covered with a confervoid growth which had an unpleasing appearance to the eye, and in consequence of which I had been obliged to paint the glass on the exterior to prevent this growth from increasing to too great an extent, It was also an unnatural mode of illumination, as all the light should pass through the surface of the water. The front towards the room and the observer was constructed of plate glass, the whole being set in a stout framework of zinc, and cemented with what is known under the name of Scott's cement, and which I have found to answer for the purpose most admirably. Within this tank were arranged several large pieces of rock-work, thrown into an arched form, and other fragments were cemented in places against the slate at the back and ends, and at parts along the waterline, so that the creatures could hide themselves at pleasure; a short beach of pebbles was also constructed in order that shallow water could be resorted to if desired. The whole tank was covered with a light glass shade to keep out the dust, and retard evaporation.
"With the sea water obtained in January, 1852, I have been working without cessation up to the present time, agitating and aërating when it became foul during the unsuccessful experiments on the seaweeds, but since then it has been rarely ever disturbed; the loss which takes place from evaporation being made up, as before stated, with rain or distilled water."
My own experiments with marine animals and plants were commenced about the same time as Mr. Warington's, namely, at the end of January, 1852. I was not aware till long afterwards that either that gentleman or any one else had proposed to effect such an object, which had been occupying my mind for some time. My success, which was less perfect than Mr. Warington's, I published in the "Annals of Natural History" for October, 1852, and subsequently, in my "Rambles on the Devonshire Coast." Traveling for health, the want of a fixed residence prevented my prosecuting my experiments with sufficient care and perseverance to ensure full success; besides which my ultimate object was rather the study of the habits of marine animals, to which end the Marine Aquarium was merely (or at least principally) accessory.
Finally, the complete success of the interesting exhibition opened to the public last year at the Zoological Gardens in the Regent's Park adds its confirmation to the practibility of the Marine Aquarium. At the time that these sheets go to press, several of the Tanks contain sea-water which has not been changed for more than seven months; and several of the animals survive, which were placed therein nearly a year ago. The high health, liveliness, and fine condition which they exhibit are patent to every visitor; while the botanist sees with great interest a luxuriant crop of marine plants which have grown in this state of confinement. They are, I believe, exclusively, of the Chlorospermatous Order; Ulva, Enteromorpha, Conferva, Bryopsis, &c. Of the last-named genus a profuse growth enveloping a stone in one of the central Tanks forms an object of surpassing beauty.