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from four to eight fides ; but the hexagonal culiar figure, tending in many places to run columns are as numerous as all the others into regular forms, resembling the th:00 together.

of salts, and many other substances during a " On a minute inspection, each pillar is hatty crystallization. found to be separable in several joints, whose “ Uuder thuis great bed of stone stands a articulation is neat and compact beyond ex. second range of pillars, between forly and preffion; the convex termination of one fifty feet in heigl, lefs gross, and more jant always meeting a concave focket in the tharply defined than those of the upper story, next; befides which, the angles of one fre- many of them, on a close view, emulating quently thout over those of the other, so that even the neatnefs of the columns in the they are completely locked together, and can

Giants Causeway.

This lower range is rarely be separated without a fracture of some borne on a layer of red ochre ftone, which of their parts.

serves as a relief to thew it to great advan" The sides of each column are unequal tage. among themselves; but the contiguous des " These two admirable natural galleries, of adjoining columns are always of equal di. together with the interjacent mass of irregumensions, so as to touch in all their parts. lar rock, form a perpendicular height of 170

" Though the angles be of various magni- feet, from the base of which the promontory, tudes, yet the sum of the contiguous angles covered over with rock and grass, flopes. of adjoining pillars always make up four down to the sea for the sp?ce of 200 feet right ones. Hence there are no void spaces more, making in all a mass of near 400 feet among the basaltes, the surface of the cause- in height, which in beauty and variety of its way exhibiting to view a regular and con- colouring, in elegance and novelty of arpact pavement of polygon sones.

rangement, and in the extraovlinary magni“ The ouifide covering is soft, and of a ficence of its objects, cannot readily be rival.. brown colour, being the earthy parts of the led by any thing of the kind at present ftone nearly deprived of its metallic prin- known. ciple by the action of the air, and of the ma- “ At the distance of eight miles from nne acid which it receives from the sea. hence the promontory of Fairhead raises its

“ The leading features of this whole coast lofty summit more than 400 feet above the are the two great promontories of Bengore sea, forming the eastern terniination of Bally. and Fairhead, which stand at the distance of cattle bry. It presents to view a valt coineight miles from each other ; both formed pact mais of rude columnar ftones, the forms on a great and extenfive scale, both abrupt of which are extremely gress, many of them towards the sea, and abundantly exposed to being near 150 feet in length, and the texture observation, and cach in its kind exhibiting so coarse, as to resemble black scherle Itone, noble arrangements of the different species rather than te clofe fine grain of the Giants of columnar basaltes.

Causeway bafaltes. At the base of these gio “ The former of these lies about seven gantic columns lies a wild waste of natural miles west of Ballycastle, and is made up of ruins, of an enormous size, which, in the a number of capes and bays, the sout ensemble course of succeilive ages, have been tumbled of which forms what the seamen denominate down from their foundacions by ftoims, or the Head of Bengore.

foine more powerful operations of nature, " The most perfect of these capes is called These mative bodies have sometimes with Pleukin. Its summit is covered with a thin food the shock of their fall, and often lie in graffy fod, under which lies the natural rock, groupes and clumps of pillars resembling' having generally an unform bard surface, many of the varieties of artificial ruins, and somewhat cracked and fhivered. At the forming a very novel and Atriking landscape, depth of ten or twelve feet from the summit, “ A savage willness characterizes this this rock begins to assume a columpar ten- great promontory, at the foot of which the dency, and forms a range of maliy pillars of ocean rages with uncommon fury. Scarce a basaltes, which stand perpendicular to the single mark of vegetation has yet crept over horizon, presenting, in the sharp face of the the hard rock to diversify its colouring, but promontory, the appearance of a magnificent one uniform greyness clothes the stene alt gallery or colonade, upwards of fixty feet in around. Upon the whole, it makes a fine height.

contrast with the beautiful capes of Bengore, " This colonade is supported on a solid where the varied brown shades of the pillars, base of coarse, black, irregular rock, near enlivened by the red and green tints of ochire fixty feet thick, ahounding in blebs and air and grass, cast a degree of life and chearfulboles; but though cumparatively regular, ness over the different objects." it may be evidently observed to affect a pe

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The

The Structare and Physiology of Fishes explained and compared with those of Man, and

other Animals. By Alexander Monro, M. D. Fellow of the Royal College of Physicians, and of the Royal Society, and Profeffor of Physic, Anatomy, and Surgery in the University of Edinburgh. Illustrated with Figures. Folio. 21, 2s. Elliot, Edinburgh, and Robinsons, London. 1785.

[Concluded from page *101] DOCTOR Monro speaking of the ear of pecially as the reader is considerably affifted

the cetaceous fishes, gives the following by references to the annexed plates, and go on account of what he observed in the dillection to the Doctor's account of some experiments of the phocæna, one of that order.

made by him in 1780, on hearing in water, « On each side of the head there is a the beiter to be able to judge of the effect of round hole, scarcely large enough to admit sound upon the ears. the head of a small pin, which is the begin- For this purpose he employed two bells, ning of a long meatus audicorius cxicimus; at the found of which he was used to; one of the bottom of whicli we find a cuncte meno them a linull tea-table bell, the other much brana tympani.

The membrare ?? pin is larger and thicker, so that the found of it conducted to the bottom of the cavity of the could be very weil hicard at the distance of a tympanum, by a chain of imull burnes, tied

qu. Tter of a mule. together by a reddith-coloured membrane. When thefe were plunged under water and The innermost piece, analogous to our j'apes, rung, no obierved that the sound of them has evidently a muícle connected to it; a 11.15 very sensibly graver ; but itil the ringlarge nerve or portio mollis di wes the iW'O ing tremor of buih was very distinguishable. branches, and then enters the bune at the On perturming an accurate experiment, the bottom of the cavity of the tympanum, and te.i-whleb:11 was found in air the highest G following one of the branches of the nerveale of barprichord; but in water it sounded a led to the cocbiea, which jj rivided into two fith faite lower, or it sounded the C thap fcole, each contamog å reddish coloured lune under the G. calily feparable from the offeous canul which lle next plunged his head under the wa. Guitains it.

ter while he rung the bell in the air, and 1 Following the other branch of the nerve, heard the found of it distinctly. As the lone I obferved at of the femicircula canals; the of the hell is louder and more acute in the · membrulle of which is very thin, and ad- air than in the water, its found is necefl:rily heres to the bone wlich cortins it.

better heard when the head of the perion The Cavity of the tympanum is renark. making the experiment is under the water ably large, and communicates freely with and the bell above il, thin when the bell is other cavities which are analogous to our rung under the water while the head is front. I, sphenoidil, and maxillary finutes. above it.

4 A ruhe aimilar to our Eustachian tube, The Dolor next plunged his whole body or iscr a palato ad axreni, begins towards the with the bells, holding their handles in his Inier end of the stuias thro' which the ani. hands, under the water, and then rung them, m. respires, and, contrary to what we 05. and was surprised with the loudness and difterve in men and quadrupeds, enloigs as it linetveis of their sounds, and could reavily runs back towards the cavity of the tympa- distinguish their different tones. num, in wbich it terminates.

In like manner, when plunged under the " While, therefore, the e animais float on water, le ítruck two stones beld in his hands i e furface of the ocean, inpreilion is made against each other, and was furprised with ca the leveral pirts of their ear in the same the tho k communicated to the cars. nanner as in man,''

This experiment conti: ms Dr. Franklin's From the remarkable difference of the opinion, “ That water will convey found fize of the caverns which communicate with farther and more readily than air. He the cavity of the tympanum, the Doctor is thinks he bas heard a smart stroke of two ted to consider, whether the effect of the ftunes together under water, his ear being found upon the er be encreased by ibai cir- also under water in the fame river, near a cumftance? or unether the chief use of theia mule : how much farther it may be heard he caverns be to render the head fpecifically know's mor, hut suppoíes a great deal farther, lighter, and like swimming biadders to make because the found did not seem faint, as if at it ne more readily wo the surface of the sea ? a distance, like distant iuunds thro' the air,

Our author next proceeds to describe the but imart and strong, as if preient just as eas in amphihinus animali, particularly the

the ear ta toxtvise or curtie, previous to his gising Our author, afterwards, by means of a of the structure of that organ in the Nantes string tied to the handle of the largest bel, Pinnati and Pilies of Linnzus. But for theie and to an inflated bladder, ince de tai we must rcfor is the work in full, niore ei- bell in a very deep pool, fix feet under :

surface of the water, and took hold of a tioned at the distance of a mile or more, with cord twelve yards long, which he had previ. one or both ears under water." oully tied to the handle. He then plunged By this means, as two very different sounds under the water and pulled the cord, and would be produced at the same inítant, the found the found was instantly conveyed to one in air and the other in water, it might be his ezrs.

'observed which of them ftruck the ear loon. He in the last place thought of trying an eit. Besides this, the flash shewing the exexperiment, to determine whether air or act time at which the bell was ftruck, the water conveyed sound quickelt: but there velocity of the found in the water might be being no lake near Edinburgh above 800 accurately determined. teet broad, he found it impollible, independe To this experiment, however, one forci. ently of the difficulty of constructing a pro- ble objection occurs in our opinion, which per apparatus, to perform the experiment in seems to brave escaped the Doctor's attention, a satisfactory and decisive way. He, how. viz. that the sound of the gun has to ever, made the following trial. He charged pass not only through the medium of air, but three English pine bottles each with about allo through that of water, before it can ten ounces of gunpowder. He then inserted reach the ear supposed to be placed under a tin tube four feet in length into each bottle, water, whereas the sound of the bell will and prevented the water from getting into pass immediately thro' the same homogeneous the bottle by wrapping a piece of wet blad- medium directly to the ear; which difference, der round the neck of it and the neck of the we apprehend, will prevent the velocity of tube which entered into it, and tying the the different sounds from being so accurately tube and neck of the bottle to each other, ascertained as might be wished.

After filling the tube with gunpowder, The teach chapter treats of the several he fixed to the top of it a piece of match pa. ways in which the tremor of sonorous bodies per, and into the match paper, just over is communicated in the different classes of the top of the cube, he put two ounces of animals to the nerves spread on the bottom gunpowder.

of the ear. He then sunk the bottle near the fue of a Speaking of the eyes of fishes, in the next lake to the depth of about two feet, and went chapter, the Doctor says, into the water at the greatest distance posli. “ In all fishes, to far as I have observed, ble, which was about 800 feet, and laid the pigment on the inner side of the choroid himself on his back in the water, with his coat is, as in land-animals which seek their food ears under its surface, and nose and eyes in the night-time, of a bright colour at the above it. The match was then set fire to by bottom of the eye ; perhaps br.cause the light another person; and as it was midnight, he strikes the bottom of the eye with less furce saw the Aath of the gunpowder contained than in the land animals, many of its rays being within the match, and soon after heard the intercepied by the water. To account hownoile of the explosion of the gunpowder ever for the different colour of this pigment, within the bottle. But he found it impoffi- in the different genera of animals, feems to ble in this way to determine the velocity of be a matrer of much difficulty : nay, it may the found with accuracy, as the gunpowder be a question, whether the chief uses of the in the bottle was not set fire to through the choroid coat in any animal have been clearly tube so instantaneously as was expected. ascertained; or whether we certainly know

For want of being provided with a proper in what manner the choruid coat is tubserviapparatus, the piece of water not being ent to the recina. Perhaps artention to the of lufficient extent, and the experiment powers of the eyes in two animals which too feldom repeated, the only conclusion the are mere varieties of the fame species, may profeffor could draw, was, that after the bot- serve to throw farther light on this curious tie burst he heard one, but did not hear two subject ; I mean the brown and the white explosions ; fo that the water seemed to rabbit : for in the former the choroid is even convey the found nearly in the same time as covered with a dark pigment; whereas, in the atmosphere.

the latter, though the choroid coat is as much The Doctor proposes the following expe- composel of veifels as in other animals, I have rimene as most likely to be fatisfactory. found that the black paint, tapctum, or inner " To fuspend under water, in a broad layer of the choroid, is altogether wanting: and lake, a large and loud sounding hell, such as bence the colour of the red blood circulating is used in church steeples, and for one per- in the vessels of the choruid, is seen when fog to strike this with an iron hammer, be- when we look into the eye, or makes their tween the handle of which and the trigger of eyes appear red.” a muiket, or cannon fired with a luck, a rope The Doctor proceeds to remark, that the was ftretched; while another person was fta- humours of the eyes of fishes are proportionally in greater quantity or much larger than my of the jepiakligo, or ink fish, which bg the fe of animals living in air : the eye of the most authors bas been ranked among the cod being very nearly of the same weight and fishes, by Linnæus placed among the worms, depth, and its axis of the same length as the but

ally

may, in Dr. Monro's opinion, most eye of the ox.

juftly be considered as a link becu ixt these After repeatedly comparing the specific two clatles of animals. gravity of the aqueous, the crystalline, and “ In this animal the ink-bag is situated on vitreous frumours of the ox and cod, by weigh the fore side of the liver, between it and the ing them in air and water, our accurate obser- rectum, to both which it is tied. It is of ver found their proporti nal weight is follows: a conical shape, and of confiderable size.

Parts The duct from it runs upwards between the Spring Water

1,000 liver and rectum, parallel with the latter, inAqueous humour

1,000 to which, very near the anus, it discharges The vitreous humour of the ox

1,016 itself. of the cod

1,013

“ As I did not observe any other bladder The whole crystalline lens of the ox 1,104 connected with the liver, I suppose that the

of the cod 1,165 ink is the gall of the animal; yet while I The outer part of the crystalline was detaching the ink-bag and its duct from Jens of the ox

1,270

the liver, I did not observe that any gall-Jucts The outer part of the crystalline were cut ; nor could I perceive, on squeezing Jens of the cod

1,140 the liver or ink-bag, that any gall or ink The nucleus of the crystalline lens was effused. Still, however, considering of the ox

1,210 the situation and connection of the ink-bas, The nucleus of the cryftailine lens this is perhaps not an improbable conjecture. of the cod

1,200

If so, we are led a step farther. I mean, that From these and other observations, the as in this animal the bile does not serve any Doctor, upon the whole, concludes, that of the purposes commonly afligned to it, but the primary use of the almost completely is thrown oui merely to aflilt the animal in fphesical figure of the crystalline lens of its eícape, there is some reason to surpal, fithes, or great couvexity, especially of the that one principal use of the liver may be anterior part of their lens, which he finds to drain off from the constitution some macter projects in the cod about seven-fortielis of that is hurtful to it, or that the bile is an exan inch beyond the iris, is to take in a luge crementitious liquor.". field of the objects round them; winch was The description of the anatomy of the abi. particularly neceffary, as the motich of their nus marinus, or sea ess, is the last article in neck is inconsiderable.

this volume, and was read to the PhilosophiHe adds, "to enable them with the fame cal Society of Edinburgh in the year 1761. length of the axis of the eye, as in the qua- This article is so curious, that though it will druped, to collect into a focus on the retina be difficult, we cannot help attempting to the rays of liglits coming from the dense abridge it. medium of water, four chief circumstances The thell of the echinus, the Doctor says, concur.

" is covered with a skin, and lias many thou* In the first place we observe, that fand thorns articulated with it by means of their cryftlline lens is more convex, mufcular ligaments. Hence the thorns ferve compofed of portions of smaller spheres, than in tlie place of feet ; and are so tenacious of in land-animads.

their powers, that I have seen the pieces of “ In the next place, we have found that a broken shell walk off in different direc. their crystalline lens is, in correíponding tions. Yet there is no appearance of any parts, much more dense than in animals organ like to the brain. which live in air.

“ It does not however follow that they " Thirdly, thrat the lens in fishes pof- are destitute of nerves ; fince there muy exit seffes power of refracting light far beyond independent of the brain, and be lo inuall as what have been calculated by authors, who to escape obiervation, have proceeded on the supposition that theie " In the interftices of the borus there powers were proportioned nearly to its 1peci- are three different kinds of bodies, soft at fic gravity.

the ends, supported on calcareous laiks “ In the last place, the vitreous humour of inclosed in a membrane, and articulated with fishes being lighter than that of lansi-animals, the shell by means of muscular membranes; no: the rays of light issuing from their lens will only the routs, but the polots of these bous, be refracted in a greater degree, or brought which are shorter than the thorns, are in confooner to a focus."

tinual motion, poflefling the powers of openThe next object of enquiry is the anato- ing and duting, like the fingers of the band.

* 'I let

or

These bodies fomewhat resemble the an- mouths of the external absorbent vefsels, I tennz of insects, and probably supply the place found that it filled and diftended compleatsy of the organs of the senses in the more per the internal leaves. fect animals.

« When after this injection I applied a “ The mouth is furnished with five teeth, magnifying glass, I could distinctly observe with large Sockets tied to the shell by a very the ducts by which the quick-silver entered Atrog membrane, around which there is pla- the doubled membrane : each leaf receives ced on the inner side of the shell, an irregu. at least two hundred branches from different har strong circle of cretaceous matter, from external absorbents. which a pair of muscles is extended to each “ The external absorbent vessel has not touth, and other muscles join the sockets of only the appearance of being muscular, but the teeth to each other."

contracts suddenly when couched with seaAfter describing the oesophagus the Doce falt; and like an earth-worm, or the protor proceeds to the rue, which, with the boscis of an elephant, pofseffes motion in all inteftinal tube, he says, are the chief parts directions; and particularly the animal por. which present within the Thell, and to which seffes the power of ftretching it to the length that part of the structure which is by far the of an inch and a half, and upwards. most interesting to the Physiologist, may be " When elongated it becomes smaller, considered as subservient. Of this he gives and the flat plate at its end is pulhed into a the following account.

conical form, the hole becoming much {maller. “ Between the inner side of the shell, and " The internal double membranc is likethe intestinal tube and roe, a large quantity wise evidently muscular, altering its shape of watery liquor is lodged, which tastes like and situation, on being touched rudely with fea-water, and is secreted from the sea-water a knife or probe, or when sea-Salt is sprinkby means of the following very beautiful led on it. Atructure,

“ There are no valves within these vessels : “ The shell of the echinus is pierced with for, from the internal trunk the doubled upwards of 4,009 holes, disposed in five membrane and the external absorbent may pairs of rows or phalanges, extending from be filled with injection. Dear the outward sides of the teeth to near No communication of the internal ducts the anus.

and plexus with the cavity within the “ These holes are disposed on the outer shell, is discoverable by the injection of quickside of the shell in pairs, and with each pair filver. an absorbent vessel corresponds.

“ On reviewing the structure of these u This absorbent vefsel in its collapsed state . ducts, there can be no doubt that the sea after the death of the animal is upwards of water is absorbed by the external openhalí an inch in length. Its end is covered mouthed vessels, and conveyed from them, by a flat plate, in the middle of which is a

through the fell into the plexus of the inhole visible to the naked eye, about the 12th ternal doubled membranes, from which a part of an inch in diameter.

secretion of part of it is made by invisible ves« From the outer edge of this plate a sels into the cavity of the thell, while the renumber of teeth project, like the teeth on niainder passes into the five large internal ducts, the wheel of a watch.

and from them thro' the receptacles at the " The flat plate is very rough, contains routs of the sockets of the teeth, to be disa fome cretaceous particles, and when pressed charged into the sea, by ten apertures at between the fore teeth feels almost like a plate their fides. of calc.

“ No other individual of the animal king* The duct from this plate to the shell is dom seems to afford such an opportunity of composed of pale.coloured circular or trans• investigating the doctrine of an absorbens verle fibres, in fasciculi or bundles, and two velfel, and of observing how is performs its small bands of such coloured longitudinal fie' office, bres are observable on opposite fides of the “ While the tube is elongated, and while tube.

the place at its end preserves the conical “ These fibres, which have the appearance figure, 1 have never been able to observe any and action of muscular fibres, are lined with motion of the sides of the hole, resembling a membrane.

the motion of the lips or moush of an animal. " When we trace the two holes which “ As the tubes are thick coated, and the pierce the shell, we find they diverge to ope sea-water has little colour, I could not pero pofite fides of the row of holes, and lead to ceive it entering into the tubes, or moving leaves or doubled membranes not unlike the within them, so as to be able, from ocular subdivisions of the gills of a skate.

demonstration, to determine the motions the " When I injected quick-filver into the tubes perform at the time they absorb. Eu7o2. Mag.

“In

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