they draw to themselves, accommodate to their nature, and turn into plants, the more fubtile parts of this mould by the co-operation of the fun, air, clouds, rains, and winds; fo that the tallest tree is, properly fpeaking, nothing but mould wonderfully compounded with air, and water, and modified by a virtue communicated to a small feed by the Creator. From these plants, when they die, juft the fame kind of mould is formed, as gave birth to them originally; but in fuch a manner, that it is in greater quantity than before. Vegetables therefore increase the black mould, whence fertility remains continually uninterrupted. Whereas the earth could not make good its annual confumption, unless it were conftantly recruited by new fupplies. The cruftaceous liverworts are the firft foundation of vegetation, and therefore are plants of the utmost confequence in the economy of Nature, though fo defpifed by us. When rocks first emerge out of the fea, they are fo polished by the force of the waves, that scarce any herb can find a fixed habitation upon them; as we may obferve every-where near the fea. But the very minute crustaceous liverworts begin foon to cover thefe dry rocks, although they have no other nourishment, but that small quantity of mould, and imperceptible particles, which the rain and air bring thither. These liverworts, dying at laft, turn into a very fine earth; on this earth the imbricated liverworts find a bed to ftrike their roots in. Thefe alfo die after a time, and turn to mould; and then the various kinds of moffes, as the hypna, the brya, and polytrica, find a proper place, and nourishment. Laftly, thefe dying in their turn, and rotting, afford fuch a plenty of new formed mould, that herbs and shrubs eafily root, and live upon it. That trees when they are dry or are cut down may not remain useless to the world, and lie, as it were, melancholy fpectacles, Nature haftens on their destruction in a fingular way: Firft the liverworts begin to ftrike root in them; afterwards the moisture is drawn out of them; whence putrefaction follows. Then the mushroom kinds find a fit place for nourishment on them, and corrupt them ftill more. The beetle, called the dermeftes, next makes himself a way between the bark and the wood. The mufk-beetle, the copper talc beetle, and the caterpillar, or coffus, bore an infinite number of holes through the trunk. Laftly, the wood-peckers come, and, while they are feeking for infects, wear away the tree, already corrupted; till the whole paffes into earth. Such induftry does Nature ufe to deftroy the trunk of a tree! Nay, trees immerfed in water would fcarcely ever be deftroyed, were it not for the worm that eats fhips, which performs this work; as the failor knows by fad experience. Thistles, as the most useful of plants, are armed, and guarded by Nature herself. Suppofe there were a heap of clay, on which for many years no plant has fprung up; let the feeds of the thistle blow there, and grow, the thiftles by their leaves attract the moisture out of the air, fend it into the clay by means of their roots, will thrive themselves, and afford a fhade. Let now other plants come hither, and they will foon cover the ground. All fucculent plants make ground fine, of a good quality, and in great plenty, as fedum, craffula, aloe, algæ. But dry plants make it more barren, as ling or heath, pines, mofs; and therefore Nature has placed the fucculent plants on rocks, and the drieft hills. The compendious Syftem of Natural History (Vol. XXIV, Page 29.) continued. With the Bignonia, or Trumpet-Tree, coloured from Nature. Note. Our Readers will be pleased to excuse a Miftake of the Engraver, in placing over this Plant the Name of Biftort, or Snake-Weed. This genus of plants was established by Dr. Tournefort, who gave it this title in honour to the late learned Abbé Bignon, who was principal Librarian to the King of France; and he ranged it in the third fection of the first clafs of plants, intitled, Herbs with an anomalous flower of one leaf, fpreading open at their brim: Mr. Ray places it in his nineteenth clafs of plants, with a labiated flower of one leaf, which is fucceeded by pods; and Dr. Linnæus puts it in his fourteenth class of plants, fhews a flower opened lengthways, with e two longer and two fhort ftamina, and epointal fituated between the two long amina; c, represents the pod, when full gown, and the feeds ranged imbricatim, ike tiles on an houfe; d, a fingle feed aken out of the pod, with its wing adering to it. This fpecies is, by Mr. Catefby, titled ignonia fraxini foliis, coccineo flore mipre; i. e. Bignonia with ash-leaves, and fmaller fcarlet flower. He has given a gure of it, but it wants the feed veffel; ad the colour of his flowers is much more ke the larger fort, which Dr. Tournefort tles Bignonia Americana fraxini folio, ore amplo Phoenicio, Inft. R. H. 164. This laft has been many years an inhabiint in most of the curious gardens in Eupe; but was brought from North Ameica, where it grows naturally in the woods, aftening its branches to the tall trees, by he roots which are fent forth at the joints, thereby they are fupported, and mount up > the top of the higheft trees. And, when hey are planted near walls, the roots will aften themselves into the joints of the wall, nd, where they have room, will rife to the eight of fifty or fixty feet. This larger ott is figured by Cornutus, Ferrarius, and veral other botanifts, by the title of Gelfeinum Hederaceum Indicum, from the re femblance of its flowers to thofe of the Jafmine; and the French do now call it Jaf min de Virginie; but in England it is generally known by the title of Trumpetflower, or Mexiocitle. The plant here figured is, by many botanifts,fuppofed to be only a variety of the larger fort; but all the plants of this fort which? have been raised from feeds in the English gardens, for several years paft, do retain their difference; fo they may be allowed to be diftinct fpecies. There are two old plants in the Chelsea garden, one of each fort, which have grown near each other above fifty years, and do conftantly produce flowers every year, which are remarkably different in their fize and colour, as alfo in the fize and shape of their leaves; but it is of late years that this fort has been much propagated in the English gardens. The feeds of it were fent from Carolina in 1724, by Mr. Catesby, from which many plants were raised; and fince that time the feeds have been frequently fent to England from that country, and great numbers of plants have been raised in the gardens; but the plants which have been raifed from feeds are feveral years before they flower,: and are not near fo productive of them as thofe plants which are propagated by fuckers, or cuttings from old trees. Tew Anatomical Obfervations and Difcoveries.-From the Hiftory of the Royal Academy of Sciences at Paris. M. Haller has obferved dance after the half vein as far as the brain, in the ower vena cava as far as the thigh, and in e fubclaviar as far as the bafilica, a very nsible alternative motion, and depending ot on that of the heart, but on that of the spiration: Thefe veins fwell and are led in expiration, but fink and empty emselves on the contrary in infpiration. This acceleration in the course of the inous blood is a new use of respiration at had hitherto escaped anatomifts. It is commonly believed that the ligature the nerves and the wounds of the tenns are infallibly attended with fatal conquences: M. Haller's obfervations have monftrated that, if this be true with red to the nerves, it is not at leaft so witht fome restriction. The ligature of the ves has often killed animals in the first fuing days; but, this time of danger over, = animal recovers, and refumes even the - of the limb the ligature had rendered alytic. As to the tendons, they did not in endowed with a great fenfibility. M. cutting of the tendon of Achilles. The cutting of the periosteum has occafioned no cries in a dog, who notwithstanding fetched many fharp and piercing at the least wound made in the skin. The dogs that served for thefe experiments have been cured by, licking themselves, and without any dangerous fymptom. His experiments proceeded even to the membranes of the brain: He opened the dura mater, and touched the pia mater with butter of antimony, yet the ac-. tion of this cauftic excited no fign of pain in the animal. These experiments feem to indicate, that much may be abated in the degree of fenfibility heretofore attributed to the membranes and tendons. C One of M. Haller's pupils obferved in falmons a penis exerted about an inch, and refembling the glans in quadrupeds. He even remarked feveral ducts having a communication with what is called in fifhes the milt. In confequence of this obferva-, tion, fishes enter the usual natural order, in which they only differ by an inftantaneous copu copulation, and operating with organs much lefs in proportion than in other animals. To this obfervation M. Haller has joined another of M. Meckel, a correfpondent of the Academy, on the organ that puts amphibious animals in a condition to remain fo long under water. M. Meck finds the reafon of this property in two vei fpacious veinous finus, which these anima have, and in which the blood is collected whilft the route of the lungs is obstructe against it. The GENIUS of the Ancients in the Art of Defigning and Engraving, exemplifie in the Explanation of a curious filver Medal and two ancient Stones. T From the Memoires de Trevoux. HE filver medal, as ingenioufly in vented as it is fcarce and valuable, was lodged in the cabinet of M. le Hay; and Crotomis, whose head, crowned with laurel appears on it, with his name KPOTOMIE, was one who won the prize at the Pythian games. He feems to be young; and this piece is probably a monument of his first victory. Nothing could be contrived more proper than the reverse of the medal: Hercules in his infancy parts and ftifles two ferpents, which Juno had fent out of envy to destroy him. This reverfe is one of the finest works of antiquity: The action of Hercules is expreffed with a force and delicacy the Roman coiners could never attain to. The fignification is not very myfterious, it being plain that the design of the medal is to fhew, that young Crotomis would overcome envy as eafily as Hercules, when a child, overcame the ferpents fent by Juno. Befides, the young vanquisher might have fome other reafons to pitch upon this fymbol: Perhaps he was a Theban as well as Hercules, who is accounted one of the firft victors in the Pythian games. What remains is only to determine the time when that medal came out, which cannot be done without touching upon the hiftory of the Pythian games. The great antiquity of thofe games, mentioned by the poets, appears to be fabulous. If we may believe them, they were founded by Apollo, vanquisher of the ferpent Python, and re-established at feveral times by Jafon and Diomedes. But it feems the firft celebration of those games is not fo ancient: They were appointed after Erylochus had deftroyed Criffa, and punished the Cirrheans and Amphiffians for the robberies committed by them upon those who went to confult the oracle of Delphi. It was then the Amphyctions, the common Judges of Greece, who generally kept their court at Delphi, being fenfible that the Olympic games were of great use to reunite the Greeks, established the Pythian games, to be celebrated, as the Olympic, every five years. The firft were celebrated the third year of the XLVIIIth Olympiad, 584 years before the Chriftian æra. The prizes propo. fed to the vanquishers were brazen tripod: which were changed in the fecond Pythia into crowns of laurel, for a greater confor mity with the Olympic games, the priz whereof was a crown of leaves of the olive tree. The medal cannot be older than this fe cond Pythiad, 580 years before Chrift; bu it may be of a much later date, fince thef games were continued for several ages. I is impoffible to determine more precifely the time when Crotomis got the victory and it is equally difficult to guefs in what fort of game he fignalised himself; for a Delphi, as well as at Elis, wrestling, running, driving of chariots, playing at quoits, and fighting with a ceftus, were the exercifes for the prize of which they contended. There was also a prize for those who fung beft, playing upon the flute or the lyre. Hefiod loft the prize, because he could not fing in tune with an inftrument. Not to mention the different changes introduced into these games, one only need be noticed, which might bring the time of this medal nearer ours. In the 344th year before Chrift, in the LXIft Pythiad, the Amphyctions proposed a prize to the young wrestlers, and Laidas won it. Very probably Crotomis won his in one of the following Pythiads: He would thus have a greater conformity with Hercules; and the reverfe would be more fuitable to him. As to the two ancient ftones, one of them a cornelian, which was lodged in the cabinet of M. Bourdaloue, feems to have been engraved for Alexander, by the famous Pyrgoteles. The perfection of the work dif covers immediately the hand of that excellent artist; but the intelligence of the figures reprefented upon the stone is a convincing proof that it was wrought by him, and defigned for that Prince. A woman puts her left foot upon a man's head, cut off from his body, and ftrives to detain a warrior, who parts from her with horror. This will eafily bring to mind a noble action of Alexander, mentioned by Quintus Curtius, Book VIII, Chap. 3. Spitamenes, a friend to the perfidious Beffus, who murdered Darius, believing that |