14 AUGUST 1858, Page 18

. RYMER JONES'S AQVARIA.N NATURALIST. * THE object of Professor Rymer

Jones's publication is very similar to that of many other books which have appeared on the subject of the aquarium but he deals more with the principles of the scientific tank and less with the meohanicals than his predeces- sors, while he more thoroughly enters into the natural history o its occupants. They tell you the story of the aquarium with mi- nute directions for making it. The Professor of Natural History and Comparative Anatomy at King's College shows the necessity of supplying the salt water of the tank with oxygen to sustain animal life by a reference to the ocean itself, animating his expo- sition by a glowing description of the sea in the calm and brilliant beauty of a summer morning, turning ere eventide to a lowering and violent gale. "The sun becomes obscured, and the breeze freshens from the sea; dark clouds are gathering on the horizon, and the tide begins to turn' the heaving waves now tumble towards the shore, and as they break, ie angry foam, portend a storm. The sky looks threatening, and the thunder growl,' far in the distance. The sea awakens as from slumber, and the blackening heavens lower over its dark bosom ; while the rising blast, impelling all the

i waves, drives them upon the rocks n sheets of feathery foam, lashing then on to madness, till at length ocean and sky seem mingled. * * * "Such are the changing aspects of the sea, and such the efficient means whereby Nature ensures the renovation of that element, the mighty deep, the grand antagonist of all the earth—refreshing it throughout its broad do. mains keeping its waters wholesome—filled with air, and thus adapted to

afford means of respiration to the living things that flourish in its vast recesses. It is evident, that it is only by imitating the conditions ob- servable in Creation that we can ever hope to succeed in our attempts at keeping alive and in health for any lengthened period animals that we de- sire to preserve in our vivaria, and it is not difficult for the observant mind to perceive how those conditions are to be fulfilled. Water itself, while in a stagnant state affords no air such as can be respired by any animal. To fill it then with atmospheric air, or oxygen, the purer element must be the first essential; secondly, to keep it stored with food adapted to the nourishment of those creatures that we place in it, is as imperatively requisite. The storms that tempest ocean,. making the sea to boil like a pot,' effect the former condition by commingling the air of the atmosphere with the waters of the sea. The vegetation which clothes the rocks and carpets the shallow; or floats through every region, when exposed to sunshine, as we all well know, pours forth oxygen gas in abundance sufficient to replace that which is consumed by respiration, and moreover yields such ample stores of food as will supply all the vast hunger of the mighty deep. With these two grand facts before us, it is manfest upon what principles an aquarium ought to be established."

The application of these principles to the construction of the aquarium is next handled, though still broadly and generally. The drawing-room tank is an ornament, a luxury, a curiosity; but glasses, dishes, pans, will answer the mere purpose of sus- taining life as well—for some scientific observations and experi- ments they are better. And in the course of this exposition one fact is brought forward of a pregnant kind. The delightful sands of the sea-shore, where we ramble to renovate health and life, are the superificial covering of a filth to which the Thames effluvia is as nothing. Could we bury the sewage ?

"Whoever upon the sea-shore takes the trouble to dig to the depth of a few inches, more or less according to the peculiar circumstances of the lo- cality, will find beneath the clean and wholesome sand a layer of black, or bluish, paint-like, stinking slime, the dregs and filth deposited, as it were, by filtration. Any one who has stood upon the beach were the receding tide, by washing away the surface-sand, and laying bare this foul accumulation, has thus stirred up the abominable odours of the Stygian pool, can vouch for the deleterious effluvia that emanate from this pestiferous deposit, which, were it not thus safely buried, would poison the entire coast, and render the shores uninhabitable. The naturalist ought, therefore to be very cautious how he allows the bottom of an old-established tank to be disturbed ; still more so in permitting the casual introduction of any shell or stone into has aquarium that is polluted with this noisome Pestilence. We have ourselves lost many valuable colonies owing to the imprudent zeal of friends, who, in their anxiety to add some new-found specimen to our stock, have neglected thoroughly to cleanse the shell, or pebble upon which it was attached, from the adherent filth."

When the subject of the aquarium is exhausted the Professor proceeds to the creatures that are to inhabit it ; and it is in this part that the peculiarity of the book consists. The author does not confine himself to giving a popular account of particular spe- cimens that can be introduced into it, but presents the reader with the natural history of some fifty genera or families, and a still greater number of species, that may, with more or less of care be preserved in the tank. The great mass of these belong. to the inferior divisions of animantia. All of these are indeed in- teresting; the most minute, perhaps, being the most wonderful, from their very minuteness. Still they do not excite the sympa- thy which man feels for the vertebrata ; and the boldness and evident purpose in action which belongs to creatures with a back- bone. The movements of fishes too are more visible than the minuter things, and less ungainly than those of shell-fish, The objection to most fishes in the aquarium is their voracious appetite. Their greediness soon makes a clean sweep. "Varied indeed, and never-failing subjects of admiration are many of the species to be met with on the coast, and were they equally harmless to their neighbours, the reader would have only to select the prettiest forms,

• The Aquarian Naturalist. A Manual for the Sea-side, By Thomas Rymer Jones, F.R.S., Professor of Natural History and Comparative Anatomy in lildg's

College, London, Pee. Published by Iran Voorst. suitable by their size or playfulness, to be the inmates of his collection ; but, as JOS been already observed in our opening chapter, the choice must be ;ada with caution, for unfortunately. the association of most of them with rarespecimens belonging to the inferior ranks of life is at all times a very hazardous experiment ; the innocence of their appearance and the gaiety of their apparel are frequently allowed to plead powerfully in their behalf, and we must therefore warn our friends against the indiscriminate voracity for which they are too often conspicuous-

" minium ne crede colon,' There are, however, a few we wish to recommend to the notice of the aqua- zllst, as being remarkable for peculiarities in their economy of sufficient im- portance to arrest attention."

The voracity of any fish cannot, howevbr, surpass or even equal that of the crab, and some other cognate gluttons with shells on their back. The disciples of Byron's "quaint, old, cruel cox- comb," Izaak Walton, maintain that fish have no feeling, and certainly these gastronomic exploits of the "edible crab" seem to support that view. Persons at a loss how to entertain their friends, may get up a minor gladiatorial show or bull-fight in a crab aquarium on humane principles.

"We had ourselves no idea,. when we consigned them to the same vessel, what a set of remorseless villains we had to deal with, and much question whether our reformatory prisons could show such an example of appropriate classification. They were of different sizes, their dimensions progressively increasing in a regular ratio, the biggest being about as large as an ordinary saucer, and seemed each of them at once to be aware of the tender mercies he might expect from his companions, although such a presentiment, if it existed, apparently interferred not a bit with his premeditated designs upon the rest. The game was not long in beginning : the first that ventured out was seized upon at once by the next in size, who, laying hold of his victim as though he had been a biscuit, with one pair of pincers, proceeded deli- berately to break up his shell with the other, helping himself to the flesh by means of his finger and thumb with as much deliberation and gusto as if he had been taking snuff from a snuff-box, and apparently caring little for the hungry eyes that seemed to glare with savage delight upon the atrocious spectacle. The Crab had, however, not very long enjoyed his cannibal feast before his proceedings were, as we thought, very unceremoniously in- terrupted by the onslaught of a stronger foe, which, seizing him exactly as he had done the first, proceeded to break him up in a similar manner, help- ing himielf with the utmost sang froid to the flesh of his already well-fed victim; while the latter, strange to say, by no means desisted from his meal upon the crab first slaughtered until quite disabled by his ruthless assailant, —affording a remarkable illustration of the absence of suffering during the infliction of the well-deserved penalty.

"On the morning following this tragical exhibition we were not at all surprised to find, that out of the six captures of the preceding day, only the two largest, which in strength and size were pretty nearly matched, re- mained alive in the tank, at the two opposite ends of' which they sat, each scowling at the other."

From the number of creatures, their habits, and habitat, treated of by the Professor, diversified as his observations occasionally- are by sketches of a naturalist's excursions, this notice conveys little more than an idea of the object of The Aquarian Naturalist, as regards its infinite variety of subjects and of facts connected with them. Much of the matter, embracing, as it does, such a great range of natural history, is of course drawn from recorded. obser- vations; but it is tested by the application of a principle, or the author's own examinations, and frequently enlarged by his ex- periments or observations. The whole is fused by his mastery of the subject, and animated by the warmth and vigour of an ima- gination, which, if sometimes rather forced and plethoric in its exercise, always excites the attention of the reader. A better "book for the sea-side" at the present season cannot be found, whether the visitor may wish to commence the study of the sea- shore or only amuse himself by an interesting pursuit, or provide a work that may be read at any time or place ; though it is more immediately fitted as a comments/7 on the wonderful works the sea-side rambler may find everywhere around him, if he will only take the trouble of searching for them.