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the ground, near the roots of trees, in such numbers, that in some places, the earth is so full of holes, it is like an honeycomb.

• Their first appearance is in an hexapode (an ill-shapen grub) with fix feet. This is their middle or nymph state: they creep up every thing near them, and fix their claws fast, on the shrubs, and bark of trees : then the skin on its back bursts open, and the fly comes forth, disengaging itself by degrees, leaving the case or exuviæ behind, in the exact shape, in which it was before occupied.

At first coming out, the Cicadze are all white, with red eyes, and seem weak, and tender ; but next day they attain to their full strength and perfection, being of a dark brown colour, with four finely-veined transparent wings, as will be better seen than described, by the specimens.

• They come forth out of the ground in the night; being then secure from being disturbed by so many creatures, that prey , on them, whilst they are under the operation of exchanging one Itate for another. From the tenth of May to the fifteenth, they are obferved to be spred all over the country.

' As soon as the dew is exhaled, the Cicadæ are very active, Aying about from tree to tree. The male makes a finging noise, calling the female, which he efects by a tremulous motion he gives to two bladders, filled with air, under his wings. From their numbers the noise is so loud and troublesome, that it interrupts conversation with a continual dinn, from morning to evening. They continue coupling to the sixteenth of May : soon after the males disappear, and the females lay their eggs. They are much larger than the males. .. They never could be perceived eating any thing; yet, as they are furnished with a long proboscis, which they frequently extend, they may suck the dews, or the farina of flowers.

· The male, in coupling, hath, at the ed of his tail, two hooks, with which he enters between the rings, that surround the body of the female. These, spreading internally, confine them long together; which may be requisite, as there is a great number of eggs to impregnate, some say fix or seven hundred.

• Soon after this work is over, the female begins laying her eggs. To affist her in this operation, she is armed with a dart near half an inch long, fixed between her breast and belly, and which extends to the end of her tail. This îne sheaths up, when it is not in use : with this dart she pierces the small twigs of trees, and, at the same time, injects an egg.' The darted twigs, engraved on the plate, will better shew the manner of this operation, than any verbal description:

• It is surprising to see how quick they penetrate into hard wood, and croud it full of eggs, the length of two or three

inches,

Gg 4

- inches, ranged in a line close together, from twelve to eighteen in each partition. How the deposites the eggs in this direction, it was difficult to discover, they are so very by whilst about this work: but my ingenious friend John Bartram, observing her, in the beginning of this operation, took a strong woody stalk of a plant, and, presenting it to her, she direcily fell to work upon it, as he held it in his hand. It was very wonderful to see how dexterously she worked her dart into the stalk, at every puncture dropping an egg. This was seen very distinctly, as she did not touch the stalk with any other part of her body.

• The Cicadze fix on most sort of trees, but like best the oak and chesnut, (which are the twigs engraven on the plate) and the fasTafras, and all o:chard trees.

They always dari to the pith of the branch, that, when the egg hatcheth, the little infect may find soft food in its infant ftate. When mature, they creep forih, go down the tree, or drop off, and soon make their way into the ground, where they have been found two feet dcep. Here they find a secure repose, until they have sailed through their changes, from a maggot to an hexapode, and lastly to a fly.

• July 15th and fixteenth they were perceived coming forth : several darted twigs were perceived, and carefully examined, and opened : fome eggs were hatched, others not mature, of a dull brown colour. These were taken out, and spread on a table; in about an hour the eggs cra ked. It was very entertaining to observe, how the little insect contrived to disengage itself, from the shell. When it was got lear froin its incumbrances, it run about, very briskly, seeking a repository in the Carth. : ThcsCicada are spred all over the country in a few days; but, being the prey of so many animals, their numbers foon decrease, and, their curation by the order of nature being short, quickly disappear.

They are the food of most kind of domestic and wild fowl, and many tealls: even the squirils grow fat with feeding on tiicin ; and one of the roparts of the indians, after having firkt plucked off their winyi, is to boil and eat them. :. There are two ditinct species of Cicadæ in North Amejica; the one here described being much larger than the other. The letir fpecies has a black body, with golden eyes, and remarkable yellow veined wings.' Art. il. An Aicount of the Plague at Conftantinople. By Dr.

Jackorzic. This paper, containing as well a natural history of the Plague, as a medicinal investigation of the dislemper and mode of cure, we are induced to rank it under the present class. The account is given in a letter from Di. Mackenzic, residing at Conftan

tinople, tinople, to Sir James Porter, his Majesty's envoy at Brussels and contains a number of particulars, contradictory to the generally-received notions of this dreadful distemper. "The ingenious Writer begins thus :

So many great men have written upon the Plagué already, “as Prosper Alpinus, Sydenham, Hodges, Diemerbroeck, Muratori, Mead, &c. that it might be justly thought presumptuous in me to touch upon that subject after them. But as I find, that they differ in some circumstances, and that some of them have had an opportunity of seeing only one year's plague; I may be allowed to write to you such remarks as I have made for almost thirty years, that I have lived in this plaguy country, without any quotations or confirmations from o:her authors; which I hope will help to reconcile the different opinions of the abovementioned famous authors. Which task I would choose rather, than to contradict them ; for I am persuaded, that each of them wrote according to the best of his knowledge (as I do myself) without any intention of imposing in the least upon mankind.

" It is beyond dispute, that the plague appears in a different manner in different countries; and that it appears differently in the same country in different years : for we find most other diseases alter more or less, according to the constitution and disposition of the air in the same climate : for, some years, fevers are epidemic, and very mortal : other years, they are epidemic, but not mortal ; the small pox the same; &c. And so the Plague is some years more violent, and has some symptoms different from what it has in other years; which, I take for granted, muft be the reason of any difference that may appear in the remarks of the celebrated authors already mentioned. There is one extraordinary symptom, which the most of these authors mention, though none of them prove it, or pretend to have seen it; which seems to me inconsistent and incompatible with the animal conomy; making still proper allowance for Omnipotence and Divine Vengeance, as in that of Sennacherib's numerous army, and many other such plagues, mentioned in scripture. What I mean, is, that a person cannot die of the Plague (such as it appears among us) instanteously, or in a few hours, or even the same day, that he receives the infection. For, you know, Sir, by your long experience in this country, that all such as have the Plague, conceal it as long as they can, and walk about as long as possible. And I presume it must be the same in all countries, for the same reason, which is the fear of being abandoned and left alone ; and so, when they struggle for many days against it, and at last tumble down in the street, and die suddenly, people imagine, that they were then only infected, and that they died instantly of the infeétion ; though it may be supposed, according to the rules of the animal ceconomy, that the noxious

effluvia efuvia must have been for some time mixed with the blood, before they could produce a fever, and afterwards that corruption and putrefaction in the blood and other Auids, as at last stops their circulation, and the patients die. This was the case of the Greek, who spoke with your master of horse, Knightkin, at, the window, anno 1752, and went and died in an hour aftera wards in the vineyards of Buiuk deré; and it was said he died fuddenly, though it was very well known to many, that he had the Plague upon him for many days before this accident happened.

• Mrs. Chapouis found herself indisposed for many days, anno 1758, and complained pretty much, before she was suspected of having the Plague. Captain Hills' sailor was infected in Candia 1730; was a fortnight in his passage to Smyrna, as the captain swore to me; yet he was five days in the hospital there before he died. Mr. Lise's gardiner was indisposed twelve days before he took to his bed, and he lay in bed eight days before he died, in July 1745ve that Thucedides in his

It is true, that Thucydides, in his account of the Plague at Athens, relates, that some were said to die suddenly of it; which may have led others into the same way of thinking: but Thucydides (vith all due regard to him) must be allowed to have known very little of the animal economy, for he was no phyfician, though a very famous historian ; and he owns moreover, that, when the Plague first attacked the Piræum, they were so much strangers to it at Athens, that they imagined the Lacedæmonians, who then besieged them, had poisoned their wells, and that such was the cause of their death. Besides, he pretends to affirm, from the little experience he had of the Plague, that the same person cannot have it twice, which is absolutely false. The Greek Padré, who took care of the Greek-hospital at Smyrna for fifty years, assured me, that he had had the Plague twelve different times in that interval; and it is very certain, that he died of it in 1736. M. Brossard had it in the year 1745, when he returned from France; and it is very well known, that he and all his family died of it in April 1762. The Abbé, who takes care of the Frank-hospital at Pera, swore to me the other day, that he has had it already, here and at Smyrna, four different times. But, what is ftill more extraordinary, is, that a your vicman, who had it in September last, with its most pa. that monic fymptoms, as buboes and carbuncles, after a fever, hoc again on the Irth of April, and died of it fome days ago, wüle there is not the least surmise of any accident in or about Conftantinople fince December, this only one excepted: but there died four persons in the same little house in September; and as the house was never well cleaned, and this young woman

always

always lived in it, she was at last attacked a second time, and died.

Having treated of the appearance and symptoms of this horrid infection, Dr. Mackenzie proceeds to throw out some philofo- , phical reflections on its rise and progress in those countries which are so unhappy as to be very liable to it.

« The Plague, fays he, is now more frequent in the Levant, than it was, when I came first into this country, about 30 years ago; for then, they were almost strangers to it in Aleppo and in Tripoli of Syria, and they had it but feldom at Smyrna; whereas now they have it frequently at Aleppo, and summer and winter in Smyrna, though never so violently in the winter; which must be owing to the great communication by commerce over all the Levant, and more extended into the country villages than it used to be. I take the Plague to be an infection communicated by contact from one body to another; that is, to a found body from an infected one, whose poisonous effluvia, subtile miasmata, and volatile steams, enter the cutaneous pores of found persons within their reach, or mix with the air, which they draw in respiration, and so advancing by the vasa inhalantia, mix with the blood and animal fluids, in which, by their noxious and active qualities, they increase their motion and velocity, and in some days produce a fever; so that the nearer and the more frequent the contact is, the greater is the danger, as the noxious particles, exhaling from the infected perfon, must be more numerous, and consequently have greater force and activity in proportion to their distance.

. Some persons are of opinion, that the air must be infected, and that it is the principal cause of these plagues; whereas I presume, that the ambient air is not otherwise concerned, than as the vehicle, which conveys the venemous particles from one. body into another, at least in such plagues as I have seen hitherto at Smyrna and Constantinople; allowing always, that the different constitution of the air contributes very much to propagate the Plague: for the hot air dilates and renders more volatile and active the venomous steams, whereas cold air contracts and more tifies them. The person having the plague may be said to have a contagious and poisonous air in his room and about him, while at the same time the open air is free from any dangerous exhalations; so that I never was afraid to go into any large house, wherein a plaguy person lived, provided that he was confined to one room.'

Dr. Mackenzie goes on to describe the symptoms of the pestiJential fever, and to give directions with respect to the method of cure; but as the present inhabitants of this part of the world are providentially so happy as to be never visited with it; we shall confine our extracts to the Doctor's philosophical and historical observations on the subject.

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