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fih fivimming about, I desired a gen- appeared to be all of one mind, for tleman, who was with me, to take a they vanished instantaneously into the loaded gun, and go bebind the shrubs mud at the bottom, raising as it were and fire it. The reason for going be- a cloud of mud. In about five minutes hind the shrubs was, that there might after they began to appear, till che not be the least reflection of light. The whole came forth again. initant the report was made, the fish
A MICROSCOPIC DESCRIPTION OF THE EYES OF THE
MONOCULUS POLYPHEMUS LINN Æl.
By Mr. WILLIAM ANDRE, SURGEON.
Read May 30, 1782.
comTHE wonderful structure of the eyes small, or lateral and interior. If the
shell were divided fairly in half, the monly illustrated by that of the Libellu- large eyes would be nearly in the cenia, or Dragon-fly, cannot fail of ftri- ter of each piece, and the finall ones king with aitonishment the naturalist on the divided edge, near the fore-part who investigates the works of the Great of the sheil. The large eyes are at a Creator in his most minute productions. great distance from each other, but the According to Lewenhoek, Hook, and finall ones are close together. It will others, the corneæ of most insects are appear hereafter, that the large eyes are made up of an infinite number of sınall, made up of a great number of small, transparent, horny lenses, each refem- transparent, amber-like cones, and that bling, in fome degree, a small magni- the small ones are composed of one fuch fying glass. This structure prevails in cone only; so that they may be divided the corneæ of insects in general; but the into eyes with many cones, and
eyes Moroculus Polyphemus, or King Crab, is, with a single cone. The large eyes, among others, an exception to this rule. or those with many cones, appear as
The Monoculus Polyphemus, or King two transparent spots about the size and Crab, is a cruftaceous animal found in nearly of the shape of a kidney bean, all the seas surrounding the continent the concave edges looking towards of America and the West-India islands, each other, and the convex towards the and which frequently grows to a very edge of the shell. If they be examined large fize*. , hall describe fo much attentively, we may discern on their of the Monoculus only as is necessary to surface a number of small depressions, point out the situation of the eyes, which point out the center of each which have been looked upon as two cone. The small eyes, or those with in number only+, though in reality a single cone, look like too small they are four. The largest piece of the transparent spots, not larger than a crustaceous covering of this animal, pin's head; these, from their minutewhen separated from the rest of the ness, are easily overlooked. shell, has very much the shape of a bara The appearances which I have deber’s bason, or the fore-part of a wo- fcribed may be seen on the external man's bonnet. The eyes are a part of surface of the shell with the naked eye; the thell, or, as Linnæus expresses it, but in order to proceed to a further inthey are tefta innatit. They may be vestigation of the subject, the cornece distinguished by the terms large and must be removed from the shell, and
applied * Bossu's Travels, vol. I. p. 368. + LINNA Syitema Naturæ, tom. I. p. 1057. I This being the case, the eyes can enjoy no motion; in which particular, as well as in fome others, the Monoculus Polyphemus differs from the genus of crabs, whose eyes are placed on petiales, or talks, and are moveable.
The Greek words Aus xents, and moros wwws, would express the fenfe in a more concile manner. Oculi palyconici ei esuli moram nici.
applied to a single microscope with a of the external cones; but this will be very strong light.
further explained, by considering that The internal surface of the large the cornea of the Monoculus may be di. eyes, examined with the microscope, is vided into layers, the number of which, found to be thick fet with a great numé however, I cannot ascertain; but I ber of small, transparent cones, of an once met with a cornea in which the amber colour*, the bases of which stand internal layer and its cones was separated downward, and their points upwards from the external lan:ina and their cones. next the observert. The cones in ge- It is very well known, that allcruftaneral have an oblique direction, except ceous animals deposit their fnells once some in the middle of the corneæ, about a-year, and are left with a soft, tender thirty in number, the direction of which covering, which, after some time, acis perpendicular. The center of every quires the hardness of the former shell. cone, being the most transparent part, As the cornea in these animals is a part and that through which the light países, of the shell, it is reasonable to suppose, on that account the perpendicular or that the interal layer is left with the central cones always appear beautifully soft covering, containing the rudiments illuminated at their points. In a word, of the future cornea; and this is the they are all so disposed as that a certain more probable, from what I have be number of them receive the light from fore observed, that I have met with an whaterer point it may issue, and trans- eye where the internal layer was sepamit it to the immediate organ of sight, rated from the more external ones. which we may reasonably fuppofe is The structure of the small eyes beplaced underneath them; but this lasting less elaborate than that of the large circumstance can only be determined ones, their internal appearance, wher in a recent subject, which I have never placed in the microscope, will be debeen so lucky as to see. The cones fcribed in a few words. They confift are not all of the same length; those of an oval, transparent, homy plate, on the edges of the cornea are the longest, of an amber colour, in the center of from whence they gradually diminish which stands a single cone, through as they approach the center, where which and the oval plate the light they are not above half the length of passes I. those on the edges.
Having thus described, as concisely As these cones so easily transmit the as posible, the fingular mechanism of light through their substance, when I the corneæ of the Monoculus, I shall add first examined them I thought they were a few words concerning their use. The tubes; but I have since viewed them lenticular structure of the cornece of inbroken in different directions, and ain sects in general certainly assists in conconvinced they are solid, transparent densing or ftrengthening the light in bodies. If they be viewed with a deep its passage to the immediate organ of magnifier, every cone appears divided fight. It is probable, that the cones in transversely by two or three internal the Monoculus have the same effect. septa or partitions. This appearance is Whether they answer that purpose, in owing to the cones themselves being a more or less perfect manner than the made
up of several cones, one within lenses in the generality of insects is another, the septa or partitions being what I cannot take upon me to deternothing more than the apices or points mine. * I have made some attempts to ascertain their number, and think they amount to about 1000.
+ This must be reversed if the eye be contidered in its natural potition. The small eyes are analogous to those small eyes of other insects which entomologists have called
Tprofefs Christianity, or to be a
ON RELIGIO N.
of God in the heart, together with
unaffected piety in the life, is the ligion of thousands, while to possess happy lot of hardly one in a thousand: the internal evidence of religion, or a many are called, but few chofen, conscience void of offence, and the love
And there the poisonous adder breeds,
Conceal'd in ruins, moss, and weeds: lic with a short narrative of the life of
While ever and anon there falls Dyer, whom he styles, with justice Huge heaps of hoary, mouldering walls. perhaps, a poet not of bulk or dignity Yet Time has seen, that lifts the low, lufficient to require an elaborate criti- And level lays the lofty brow,
Has seen this broken pile complete, cism. Grongar-Hill, he tells us, is
Big with the vanity of state; the happiest of his productions. For But tranfient is the smile of fate! though it is not indeed very accurately A little rub, a little sway,
A fun-beam in a winter's day, written, yet the scenes which it dir
Is all the proud and mighty have plays are very pleasing, and the mind
Between the cradle and the grave. is always open for the reception of the images which they raise.' To which These passages are poetical, and inewe may add, that the reflections of the rit a higher commendation than they writer are perfectly consonant to the have received. Many of the verses, general sense or experience of man- however, are weak and puerile. kind. So that, as the doctor obferves,
“ The Ilender fir, that taper grows." we believe that when it is once read, Every one knows, that the fender fir it will be read again.
must be taper. The latter part of this When we reflect, that this poem was line, also, shews, as Dr. Johnson fay's written at the age of fixteen, we drop of a line in Gray's Ode on the Cat, the pen of criticism. The ease of the that a rhyme is sometimes resolutely versification, and the train of senti- made, when it cannot easily be found. ments which it exhibits, are not com
- The purple grove, monly found at such an age. When “ Haunt of Phillis, Queen of Love!" ke is on the fummit of the hill, he This favours of the youthful poet; as, cries out:
indeed, do some other lines of this See on the mountain's southern side,
2 Where the prospect opens wide,
The scene of this poem is taken from Where the evening gilds the tide ; How close and small the hedges lie!
the vale of Towy, which derives its What streaks of meadows cross the eye!
name from the river which winds A ftep methinks may pass the stream, through it, and presents a highly culSo little distant dangers seem;
tivated scene to the eye. The woudSo we mistake the future's face,
land views, however, in it are frequent, Ey'd through Hope's deluding glass. As yon fummits soft and fair,
and the whole is wild and simple. The Clad in colours of the air,
scenery seems precisely of that kind Which, to those who journey near,
with which a great master in landscape Barren, brown, and rough appear; Still we tread the fame coarse way,
was formerly enamoured: The present's still a cloudy day.
Juvat arva videre, The description of the beautiful form Non caftris hominum, non ulli obnoxia curæ, which removed cultivation takes, dif- Rura mihi et risus placcant in vallibus amnes;
Flumina amem, fylvasquecovers the painter, and the simile derived from the different appearance of
May I the tranquil meadow share,
Which never teli che ploughman's care: evils which are near, and which are
The rivulet, winding through the vale, more removed, bespeaks a mind fraught The groves, which catch the perfum'd gale, with poetical ideas, and no common
Where melancholy never broods, share of reflection.
Nor pomp nor luxury intrudes. The following passage has great
This vale, with all its various beaubeauty:
ties, has lately been described by a very "Tis now the raven's bleak abode,
ingenious traveller. *Tis now the apartment of the toad;
however, with his own cbservation on
the enchanting beauties of this vale, he “ 'This is perfectly right; objects fo has examined the use that Dyer, as a near the eye should be diftinctly markpainter, has made of the prospect which ed. What'next strikes him is a purple offered itself to his view, with no grove; that is, I presume, a grove which common judgement and address.
has gained its purple hue from diftance; I shall conclude these remarks with this is, no doubt, very just colouring; a passage, in which the nice discern- though it is here I think introduced ntent of the artist will be found in allo. rather too early in the landscape. The ciation with the elegant taste of the blue and purple tints belong chiefly to critic:
the most removed objects, which seem “ This is the scene, which Dyer not here to be intended. Thus far, celebrated in his poem of Grongar-Hill. however, I should not greatly cavil. Dyer was bred a painter, and had sure “ The next object he surveys, is a a picturesque subject, but he does not level lawn, from which a hill, crowned give us so fine a landscape as might with a castle, which is meant, I am inhave been expected. We have no where formed, for that of Dinevawr, arises. a complete formed distance; though it Here his great want of keeping apis the great idea suggested by such a pears.
His castle, instead of being vale as this. No where any touches marked with still fainter colours than of that beautiful obfcurity, which melts the purple grove, is touched with the a variety of objects into one rich whole. ftrength of a fore-ground. You see Here and there we have a few acci- the very ivy creeping upon its walls. dental ftrokes, which belong to dif- Tranfgreffions of this kind are comtance, though seldom masterly. I call mon in descriptive poetry; innumerathem accidental because they are not ble instances inight be collected from employed in producing a landscape; much better poems than Grongar-Hill; nor do they in fact unite in any such but I mention only the inaccuracies of idea; but are rather introductory to an author, who, as a painter, should at fome moral sentiment, which, howleast have observed the most obvious ever good in itself, is here forced and principles of his art." With how much miltimed.
more picturesque beauty does Milton • Dinerawr Cafle, which stands introduce a diftant castle: about a mile from Llandilo, and the
“ Towers and battlements he fees, kenery around it, were the next ob- “ Botom'd high in tufted trees." jects of our curiosity. This castle is " Here we hare all the indiftinét feated on one of the fides of the vale colouring which obscures a distant obof Towy, where it occupies a bold ject: we do not see the iron-groved eminence, richly adorned with wood. window, the portcullis, the ditch, or It was used not long ago as a mansion: the rampart; we can juft diftinguish a but Mr. Rice, the proprietor of it, has castle from a tree; and a tower from a built a handsome house in his park, battlement. about a mile from the castle, which, “ The scenery around Dinevawr however, he still preserves as one of Castle is very beautiful; confifting of the greatest ornaments of his place. a rich profusion of wood and lawn. This
caftle, also, is taken notice of by But what particularly recommends it, Dyer in his Grongar-Hill; and seems is the great variety of the ground. I intended as an object in a distance. But know tew places where a painter might his distances, I observed, are all in study the inequalities of a surface with confusion; and indeed it is not easy to more advantage.” separate them from his fore-grounds. To these remarks little, perhaps,
“ The landscape he gives us, in can be added, as I propose to confine which the castle of Dinevawr makes a my critique to Grongar-Hill. The part, is seen from the brow of a distant other poems of Dyer have likewise hill. The first object that meets his been examined by Dr. Johnson. Ascye is a wood, it is juft beneath him; he has given is, however, but few and he easily diftinguishes the several traits of his private character, I cannot trees of which it is composed. forbear adding, that he was a virtuous
man, and poslefled a very generous join with me, in breathing a sigh to heart, and an excellent understanding.
If they were admitted The author of this paper has fre- as companions of his social hours, they quently heard him mentioned with high will peruse with mingled pleasure and praise, with great affection, and most regret, this humble but friendly refriendly regard, by a gentleman who is membrance of a man, whose mind was now, indeed, no more, but was once excellently stored, whose taste was pure, the school-fellow and intimate friend whose learning was great, whose knowof John Dyer. Should any reader ledge was extensive, and whose virtues know the name of Rayaud, they will were eminent.
TO THE EDITOR OF THE LONDON MAGAZINE. SIR, HE following letter was communicated a few years since by a very inge
nious young clergyman of the Church of Scotland to a celebrated English divine; and as it places the ecclesiastical affairs of our neighbour nation in a very clear, if not a very advantageous light, I think the publication of it in your useful miscellany will afford information and entertainment to your readers.
L. K. Rev. SIR, Y DE
OU will, no doubt, expect the able defences of revelation, are infe.
performance of the promise I rior to none in the world. But after made, to let you know in what fitua- this is granted, I doubt it will be too tion the interests of religion are among obvious that in what ought to be one us here. Yet I must own, that I en- of the chief praises of a Christian miter upon such a talk with no fmall re- nifter they are remarkably defective :luctance. 'Tis very probable I can in- I mean the teaching and avowing thofe form you of nothing that you will doctrines of the bible which are fupthink 'new or material, because neither posed inconsistent with the tenets of my business nor my inclination leads the Church of Scotland : while they me much abroad in the world: and I neglect or are afraid to do this, they am likewise heartily alhamed before- may indeed prove to great fatisfaction hand to consider how little I can say that the religion we profess was sent to the advantage of those whom I from heaven,
but it will never be clearought to consider as my brethren and ly known what that religion is. The fellow-labourers in the truth. How- middle ranks of the people who are erer, I shall simply lay before you such committed to their care, and are more matters of fact as have either come immediately under their influence, will under my own observation, or I have continue in woeful ignorance and suheard from good authority. Perhaps perstition; exposed to the derision and the reality of them might be contro- seduction of every sceptic who lies in verted by many persons who know wait to deceive. But I am wandering berter than myself. Perhaps I am mif- from the point. informed; or (it will be faid) I look Our clergy are divided (as you alupon the affairs of this church with ready know) into TWO GREAT PARprejudice and an evil eye. Yet I do
One of these, which goes unactually believe that what I represent der the name of the friti party, pofto you is the real state of our ecclefi- fesses the west country, Perthshire and astical affairs at present. Allow me, Fife:-places which have been the perhowever, first to observe, to the honour petual nurseries of bigotry, and fediof our clergy, that many individuals tion. These feem to be the genuine among them in respect of genius, lite- fons of the Church of Scotland; true. rature, juft views of Christianity, and bred Calvinifts of the house of Knox, Lond. Mag. Aug. 1783.