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Come, keep her, her course, north-east half east; crack on her; the breeze freshens; stunsails, alow and aloft. There she goes, nine knots; and to-morrow we shall be within sight of old Ireland.”
On the morning of the 3rd of June, 1838, we entered Kingstown harbour. The hour was early ; the inhabitants had not yet stirred. There was scarcely a vessel in port. A thick mist hung over Killiney hill, and every thing looked lonely and deserted; but still it was with a longing eye and a beating heart I hailed that shore, to me
“ More dear in its storms, its clouds, and its showers,
Than the rest of this world in its sunniest hours.”
A.- PAGE 64.
ON A NEW METHOD OF PRESERVING FISH FOR ZOOLOGICAL
Being the Substance of a Paper read by the Author before the Natural History Section of the
British Association - August, 1839.
A GOOD method of preparing fish for museums has been long considered a desideratum to the naturalist, but none of those that I have as yet seen preserve those two great requisites-colour and contour. This is so obvious in the distorted, faded specimens to be seen in collections, that I need not dwell upon the subject. My mode of preparation is as follows:-I make an incision through the scales down to the muscles, commencing about where the operculum joins the cranium, and continue it parallel with the dorsal outline to the centre of the tail. A similar cut is made from above the pectoral fin, till it also meets in the centre of the tail ; by this means, somewhat less than a third of one side is included between the lines. The fish is kept steady on a smooth board, to which it adheres by its own natural gluten ; water being poured over it from time to time, so as never to allow the scales to dry. The skin is then dissected back as far as the dorsal margin, where it meets the bony rays which support the fins. These are cut across, as close to the skin as possible, with a strong pair of scissors or a cutting forceps. A similar process is used towards the abdomen, taking care to keep as close to the facia to which the scales are attached as possible. The first vertebra is then separated from the cranium, and the skinning process continued by lifting up the body and leaving the skin adhering to the board ; from which it should never be removed, if possible, till the dissection is completed. Difficulty will be experienced towards the tail, where the muscles become more tendinous, and are attached to the subcutaneous facia. The
rays of the caudal fin are then divided from the last vertebra, and the body removed entire. The gills are next taken out, and any remaining portion of the flesh about the head, cheeks, or thorax. It is as well, perhaps, to leave in the scapulæ, or a large portion of them. An opening is made into the side of the cranium, where it will be found very thin, and the brain taken out. The eye is completely removed on the reverse side; a hook, passed down through the orbit, transfixes the back of the sclerotic of the other eye, in which an opening is made ; the finger then pressed on the cornea in front will squeeze out the lens and humours, retaining the iris perfect in its place; and I have lately succeeded in retaining the gills, if necessary. The tongue is left in, and the fish is then cleansed from all impurities, care being taken not to stretch the skin nor to injure the scales. It is then well anointed with arsenical preparation, or wet with the spirituous solution of corrosive sublimate. There is, however, an objection to the use of corrosive sublimate in those fishes possessed of much mucous, for it turns them white upon turpentine being applied afterwards to soften them or remove the varnish; but when the specimens are to be set up immediately, and not damped afterwards, there is no objection to it. The globe of the eye is filled with cotton from the opening in the back-care being taken to keep the iris in its natural position. The cranium is also stuffed, and flakes of tow, cotton, or any material of a similar light description, laid along the body till a sufficiency to give the form of the animal has been put in. The refleeted edges of the skin are then returned the fish removed from the board, and placed with the front up—the tail and fins expanded are pinned down in their natural position on cards, supported by little bits of cork; the fish is given its proper shape, and all the inequalities on its surface smoothed off with a soft brush. It is then set to dry in a current of cool air, with little light or sun, much in the same manner as a dried anatomical preparation, and should be carefully watched to see that it dries equally, and that no part of the skin shrinks more than another. If it should, a brush, wetted in cold water, touched upon the part, will restore it. It should be varnished the moment it is sufficiently dry, and the cards, &c., removed from the fins, which will now retain their natural position. I have tried several varnishes, and found the common copal, or mastic diluted with turpentine, the best. The cornea, which is continuous with the surrounding skin, now becoming hard and transparent, the wadding may be removed through the back of the sclerotic, and a bit of foil introduced in its place, of the colour originally possessed by the animal, in many of which we know the tapetum is very brilliant. Finally, a pin at head and tail will retain the preparation on a board, from which it stands out in bold relief, and preserves its shape and colours better than any other I have yet seen. Much difficulty will be found in skinning those on which the scales are very small, as in the mackerel tribe, and the thin skin will not, of itself, preserve the contour of the fish ; in those cases, I found that pasting a few layers of common brown paper on the inside of the skin, until it
acquired sufficient dryness to retain the position with the stuffing underneath, answered the purpose perfectly. I find this method is not so applicable to the shark and eel tribes; the most effectual mode of preserving which will be, by drawing the body through the mouth.
Myriads of small red ants swarm in Madeira. These I found so destructive to entomological specimens, that a whole trayful would be eaten up in a night; yet none of my fish suffered from them. Specimens properly prepared can easily be brought home by being pinned lightly on thin boards, and placed in boxes with an interval of a few inches between each. When dry, they do not create the slightest smell, and when brought home they can be afterwards damped, reset, and the position altered by removing the varnish with a little turpentine, and damping the interior. Should not a second specimen be at hand, or if good plates cannot be procured, I draw the outline of the fish upon a board before I commence the dissection.
The specimens in my possession have now been tested by nearly six years' trial, and though they have been subject to inuch knocking about, yet they still preserve their forms and much of their colour. Regarding the above method, in comparison with that by Dr. Parnell and others, my friend, W. Thompson, Esq. of Belfast, our most celebrated Irish zoologist, writes to me the following :-"For a private collection, portability, occupying little room, and the rapidity with which specimens can be prepared according to it, I like Dr. P.'s method very much; but for a public collection, your plan of preserving the fishes according to their natural form is, I conceive, in every point of view, incomparably superior ;" and a similar opinion has been expressed to me by Mr. Yarrell.
It is much to be regretted that, although Ireland possesses facilities for making an ichthyological collection, such as few other countries possess, (with the exception of those specimens prepared by pasting the flattened skin of one side of the animal upon pasteboard, in the collection of my friend, Mr. Ball,) we have not even an attempt at a collection in any of our museums.
I may add, that the recent and most judicious appointment of Mr. Ball to the curatorship of the museum of the University, leads us to hope that we may shortly possess a complete collection of our native fishes.
ON TRAVEL, THE EDUCATION SUITABLE FOR TRAVELLERS, AND THE ADVAN.
TAGES THAT WOULD ARISE TO SCIENCE FROM TRAVELLING FELLOWSHIPS IN THE UNIVERSITY OF DUBLIN.
THERE are two descriptions of modern English travellers ; those who travel for instruction, and those who travel for amusement. The latter and more numerous class are generally persons of large fortunes, who,