oat 7 ae qe - in z othe * po 72:9 Be! anaes : = % ee > , z 3 BPs ca: ae oe a 7 af i cee fs * - | . aS oe | | BPP yi wre . a CF de Btede porac* ACN A dO Va G Y FR. S. Didhlishd by 4 Tilloch Jan“t.1806 THE PHILOSOPHICAL MAGAZINE: COMPREHENDING | THE VARIOUS BRANCHES OF SCIENCE, THE LIBERAL AND FINE ARTS, AGRICULTURE, MANUFACTURES, AND COMMERCE. ee BY ALEXANDER TILLOCH, #ONORARY MEMBER OF THE ROYAL IRISH ACADEMY, &e. &c. &c. é : t : Z « Nec aranearum sane textus ideo melior quia ex se fila gignunt, nec noster vilior quia ex alienis libamus ut apes.” Just. Lips. Monit. Pokit. lib. is cap. te LONDON: Printed by R. Taylor and Co., 38, Shoe Lane, Fleet Street : And sold by Messrs. Ricuarpson; Capert and Davies; Loneman, Hurst, Rees, and Orme; SyMonps; Murray; HicHirery; Vernor and Hoop; Harpinc; London: BELL and Braprute, Edinburgh; Brasu and Rei, and D. Nevin, Glasgow; and Gitpert and Hopces, Dublin. 1805. CONTENTS OF THE TWENTY-SECOND VOLUME. 1. EXTRACT of two Letters from Captain Von KrusEN- sTERN, Commander of the Russian Expedition to Japany dated the Harbour of St. Peter and St. Paul, July 19, » and August 20, 1804 iieeccee cess cece ed ern eens 3 fore them in their Passage to Leeward 1... 4.4. +4 4: 14 IIs. Twenty-second Communication from Dr. THORNTON relative to Pneumatic Medicing.... 0... cece ee cease 25 IV. On the Action of Platina and Mercury upon each other. By Richarp Cuenevix, Esq. PRLS. M.R.LA. AS aD mish owadbisig'a. slciaahwass Qh amis lnva's Sails 5 He 26 V. An Account of some analytical Experiments on a mineral Production from Devonshire, consisting principally of Alumine and Water. By Humeury Davy, Esq. FR.S. Professor of Chemistry in the Royal Institution...... 35 VI. Experiments on Wootz. By Mr. Daviv Musuer 40 VII. An Essay on Medical Entomology. By F. Cuavu- METON, Physician to the Army .....ser eee cence 4g VILL. Short Account of Travels between the Tropics, by Messrs. Humpouipr and BoNPLAND, 22 1799, 1800, 1801, 1802, 1803, and 1804. By J. C. DELAME- THER UB g) s).Varcisttele ngs ever s © Be) Natori dtobeises Wales yale tem 54 1X. An Account of Sutton Spa, near Shrewsbury. By Daiwawet: and August 20, 1804, We airived Hetc on the 18th of July, and are now ac- tively employed in unlading the ship and taking in ballast. Agreeably to our original plan, we ought to have proceeded directly to Japan; but as it appeared to me impossible that , the business of the embassy could be terminated soon enough to return in the course of the same year to Kamt- chatka, as several months would be necessary only for transportirig the presents from Nangasaki to Jedo, I re- Solved to proceed first to Kamtchatka in ofder to unload the vessel there, and then set sail for Japan, where we otherwise must have remained the whole winter. The dif- ference of two months later could be of little importance to the embassy; while, on the other hand, if the lading, respecting the value of which I had formed an improper idea, as from {1000 to 2000 pet cent. may be gained on some articles, had remiairfed a whole year in the ship; the half of it at least must have been lost; for already some of the articles have been spoiled by dampness. In regard to my voyage from Brazil to Kamtchatka, which took up five months and a half, during which, nine days excepted, we were. continually under sail, and which in every -respect was exceedingly fortunate, I intended to haye transmitted to you a complete journal of it; but as Dr. Espenberg has told me that he proposes to send you one, and as there is reason to expect that his information will be more inteyest- ing than mine, which would contain rather nautical than historical events, I am happy to think that you will be in- formed by him of every thing that distinguishes our expe- dition from others of a similar kind. The account of our residence at the island of Nukahiyah, respecting the nature and inhabitants of which nothing has yet been known in Europe, is the only thing new that you can expect. The Vol. 22. No, 85. June 1805. A2 Sandwich 4 Russian Expedition to Japan. Sandwieh islands are too well known for me to regret having been prevented by want of time from touching at them. ‘he changes, however, which, have taken place in these islands since the time of Vancouver, and which must be considerable, will be accurately described by capt. Lisi- anski, as he undertook to remain there at least a fortnight. {t appeared to me of some importance to examine Easter Island: the information which Roggewein and La Perouse haye given us respecting it (for the Spaniards have published no account of it) proves that it has experienced great changes. T-consequently was desirous to ascertain whether the bene- volent views of the French voyage of discovery in regard to this island had been accomplished, and therefore resolved to come to anchor there for some time; but the strong north winds rendered this impossible, or at least prevented us from doing it without considerable loss of time,—a sa- orifice which in my present situation I could not venture to make. Capt. Lisianski, from whom we separated when we doubled Cape Horn, remained some days in the neighbour- hood of it, but without coming to anchor, and without having any communication with the mhabitants, who pro- bably, for want of canoes, of which they had some in the, time of Cook and of La Perouse, did not eome on board. My passage from this place to Japan will exhibit no variety, for on account of the lateness of the season I must use as much dispatch as possible to arrive in proper time at Nan- gasaki. But, if circumstances permit, I hope that my re- turn from Japan will prove of some benefit to geography, Journal of the Voyage from Brazil to Kamtchatka; ex- tracted from a Letter of Dr. EspenBerc, dated the Harbour of St. Peter and St. Paul, August 24, 1804. * That we were obliged to remain at the island of St. Ca- tharine frony the 21st of December to the 4th of February, because the Neva stood in need of two masts, is already known to you. On the 4th of February we hove up ous anchors, and as soon as we had got to a sufficient distance from the land we directed our course southwards. On the 25th we saw land at a great distance: it proved to be Cape St. Jolin, the eastern extremity of Staaten Land. This land is exceedingly high, and in consequence of the great di- stance looked like a clond. _ People unacquainted with nau- tical affairs, to which class our naturalists belong, were ex- tremely sorry that the smp did not approach the land. I myself was at first in the same situation; but the captain assured me that the winds near the land are sa a i le, Russian Expedition to Japan. 5 ble, and that gales and calms often take place. In conse- “quence of these‘calms, vessels are often in danger of being ‘ ae on shore by the currents and breakers, and therefore it was not advisable without necessity, and merely forthe sake of gratifying curiosity, to run such a hazard. At Stdaten Land the current is remarkably strong. I was told by the captain of an American ship at St. Catharine, that he was once carried by the current through the strait of Le Maire in one night, contrary to his intention, and with- out knowing it. At one time he saw, to his great terror, the Jand on both sides; but not long after he found himself again in the open sea. If this be true, he was truly for- tunate. We did not pass through this strait, but sailed to the eastward, around Staaten Land. From St. Catharine to this place nothing remarkable occurred. Between lat. 46° and 53° south, we saw a great number of whales. One night the Neva struck against something, which in all pro- bability was a whale. The greatest southern latitude to which we were obliged to proceed on account of the wind was 60 degrees. Whether we really doubled Cape Horn, or not, in the proper sense of the term, I cannot with cer- tainty affirm. On account of the north-west winds, which blow here so incessantly, and with so much violence, the captain is of opinion that navigators cannot be sure of con- tinuing their voyage with safety in the ocean till they have sailed round the whole of Terra del Fuego. It is well known that capt. Bligh, who advanced so far as 78° west longitude from Greenwich, was obliged to return and steer for the Cape of Good Hope, in order to reach the Sandwich islands. On the 20th of March we were opposite to Cape Victoria and the Straits of Magellan. Cape Horn is not entirely undeserving of its bad name: it was stormy enough, and the land very high. How often we experienced storms [ cannot exactly say. The eye becomes accustomed to heavy seas, and, by habit, the howling of the winds ceases to excite alarm. During these storms the heavens were filled with clouds; in the course of one of them we were separated from the Neva, and did not see her again till we reached the Marquesas, where shearrived three days after us. The captain intended to remain some days at anchor at Easter Toland, but the wind prevented us ; and, as we had resolved to proceed first to Kamtchatka, he was unwilling to lose time to no purpose. We therefore directed our course to the Marquesas. On the 6th of May, early in the morning, we saw Hood’s A3 Island, 6 Russian Expedition to Japan. Island, discovered by Cook: towards noon we came in sight ot the island called by Hergest Rious Island, which belongs to the group of the New Marquesas, and which Ingraham, an American, the first discoverer, called Washmeton’s Island, and Marchand, a month later, Isle de la Revolu- tion. The largest of all these islands, that to which We properly steered, and which by Marchand is called Isle Baux, but in the language of the natives Nukahiva, we saw towards evening. ~ ° mere On the 7th, ‘at noon, we were pretty near to the shore. Our expectation was on the stretch as we approached it, but no canoe appeared ; which was rather a disappointment, as, according to the accounts of all navigators, these islan- ders venture ‘a great way out to sea. “The captain suspected that the master’ of some American ship must have behaved fll to the natives, and that this might serve to account for their timidity. At length two boats were dispatched to ex- plore the bay of Anna Maria, so called by Hergést. “When these boats were about a verst distant from us, we ob- served a canoe making towards them. Our expectation was now at its height: we saw the canoe approach the first boat, and in a few minutes both of them rowed off together: our boat proceeded forwards, and the canve, which steered for the ship, approached the second boat. We could now plainly perceive that all the people in it were naked; one of them, who was of a somewhat lighter colour, we took to be their chief or king; for we are told by navigators that the higher ranks have a whiter colour. ’ This person stepped into our boat, and the crew of our ship all exclaimed, ‘* The king ! the king!” The boat and the canoe then both rowed to- wards the ship.’ We now observed something in the water near the canoe, which we at first believed to be an islander swnnming; for we knew from books of voyages that they are very expert at this exercise. “A man swimming! a man swimming!” was repeaied both in Russian and Ger- man. All hurried to the head of the ship, and one climbed up on the shoulders of another. On their nearer approach we discovered to our regret that the excellent swimmer who had afforded us so much satisfaction was an outrigger or cross pole placed’ over the canoe, which was not above a foot in breadth, ‘to defend it from being injured ‘by the | rocks. When ‘the islanders got close to the ship; the light: | colourcd'person climbed up, and, to dur astoriishment, ad- dressed us in English. We soon found that he was an Englishman, who had already spent five years in the island: he was almost entirely naked, having only. a narrow girdle tied Russian Expedition to Japan. 7 tied round his middle, and was tatooed on the breast. The canoe rowed past the ship, and the men addressed to us a kind of speech. The index finger of their right hand was always stretched out, and they moved it towards us nearly in the same manner as when a person threatens. Mr. Ro- berts, for such was the Englishman’s name, informed us that this motion was an assurance of friendship. At length one of the natives in the canoe took courage and clambered up the side of the ship: he was the king’s brother. He was exceedingly timid: sat down at the Eng- lishman’s feet, grasped one of his lees, looked round with great fear, and pressed his face, as it ashamed, azainst the back part of the Englishman’s thigh. He was followed by another. We endeavoured to inspire him with courage ; patted him, and called him our tayo. We firmly believed that this word signified friend; but this is not the case, M. Fleurieu, the editor of Marchand’s Voyage, must there- fore pardon me for suspecting that he copied the following passage,—Vous étes nos amis, et vous nous tuez, from Bou- gainville. Their attention was much attracted by our fowls, and some small papajays from Brazil: they squatted down before them and stared at them with their mouths wide open, These people have limbs remarkably pliable. Very old men will often sit down on the ground without ever assisting themselves in the least with their hands. They do not stretch out their legs when they sit, but squat down with their knees bent like young children. This may be in some meaSure owing to the frequent use of coco-nut oil, with which they besmear their skin to keep it soft and pliable. Towards noon we came to anchor in Anna Maria Bay, at the distance of aout a verst from the nearest shore ; which, however, was only a barren rock. The shore on the other side, which was about two versts distant, was covered with beautiful trees, and exhibited a most charming prospect, especially to people who for thirteen weeks had not seen land; for the view of Cape St. John scarcely deserves to be mentioned. We now saw two groups which had the appearance of water fowl, not far from the inhabited part of the coast. As they approached us we perceived them to be natives; and among them were some small children, who sometimes laid hold of their stronger neighbours with one hand, again let them go, and continued swimming alone. They surrounded the ship, and their number gra- dually increased till the whole place swarmed with them, they seemed highly gratified, kept continually laaghing, ; A4 and s Russian Expedition to Japan. and did every thing in their power, by gestures and tricks of every kind, to attract our attention. They threw them- selves into all sorts of postures, lay sometimes on one side and sometimes on their back, elevated their legs, &c. The women in this respect did not yield to the men; and the object of their pantomime might easily be comprehended. When a piece of a coco-nut was thrown at them from the ship, or when any of the sailors spat down upon one of them, the astonished savage immediately became an object of Jaughter to the rest. The natives brought us coco-nuts, bread-fruit, and bananas. The two latter articles, at this season of the year, were scarce. When any of them’had obtained, as the price of their wares, a small piece of iron, or an old nail, they burst out into an immioderate fit of laughter; the reason of which, as appeared, was, that they thought we had been mosi egregiously cheated. When they received nails from us, they stuck them into the. laps of their ears, the holes in which were so susceptible of ex- tension, that they did not seem to be incommoded by a large rusty nail. Mr. Roberts told us that there was a Frenchman in the island; but he cautioned us against him, as a man of a very bad character. While we lay at anchor the king or chief of the bay, Tapeka Ketenue, came tous in a canoe, and among his retinue was the Frenchman. As I do not understand English, I was extremely glad; but this Frenchman had so much forgotten his mother tongue, that he was become a real savage. All that he was able to say was,—Oui moi beaucoup Frangois, Americanish ship, ah dansons la Car- magnole! He would then laugh like a native of Nukahiva, to whom he had a great resemblance, as not only his body but the greater part of his face was tatooed. He understood English pretty well, as he had been accustomed to converse with the Englishman in this language. He told us, that he had come to the Marquesas in an American ship; that this ship had been on the whale fishery; and that from the whales coco-nut oil was obtained. The person called by the Englishman the king, though. that title. did not seem at all suited to him, was a man of about forty or fifty years of agé, tatooed over his whole body, except on the palms of the hands and the soles of the feet: -he viewed his corpulent person with great satisfaction in the captain's looking-glass, and was highly delighted with the presents | which he received. } Next day, the 8th, we went on shore: we were all armed; and the sailors, who had muskets, pistols, and sabres, kept the . ~ Russian Expedition to Japan. 9 the natives in awe. Having landed with great difficulty, on account of the strong surf, the people surrounded us with every token of joy: they ran round us singing and dancing, while Ketenue’s paternal uncle, who, however, was always called his father, kept them in order with a long pole, but without ever striking any of them. We entered Ketenue’s house and saw his whole family, con- sisting of his wife and daughters. He then conducted us into another house adjacent, but as it was zaabooed none of the natives durst follow us. The place on which this house stood was elevated, and paved with stones. We here remained unmolested, and were regaled with the kernel of the coco-nut, and had some of the liquor to drink. Ke- tenue often paid us a visit, and always received a present: but the natives set so much value on their swine that we could obtain from them only five, which were all of a small size, On the 9th we received information that a ship was in sight; and on the 10th the Neva arrived. Ou the 13tha Jarge body of us, for we were accompanied by some of the crew of the Neva, went on shore well armed; and after viewing the morai, which is here called wahitaalboo, we paid a visit to Roberts and Ketenue. By an accident I Jost a great many of my papers, among which were three sheets respecting Nukahiva. This, I know, is no serious loss; but I must make an apology for presenting you only with fragments. I cannot comprehend why the beanty of the women of the Marquesas has been so much extolled. In regard to the face in general, | shall say nothing; but their persons are altogether ugly. They are small, and of low stature: their arms are proportionally thin, and the lower extremities thick and clumsy. When a female has attained to the full rowth, that is to say, the ave of fourteen or fifteen, her enor are quite flaccid, and hang down. Children of the age of nine or ten came on board our ship, many of whom were married. ‘All those who came on board were quite, naked. Some of them had a cord tied round théir middle, from which were suspended two leaves, one before and the other behind. On shore we saw several who had fastened round them a piece of cloth made from the bark of the paper mulberry tree; and others were painted yellow with the juice of the curcuma root. They were not much tatooed, and only on-the arms and shoulders, with some transverse strokes above the lips. _The males are very fine men, of a good stature, and have well a Russiun Expedition to Japan. well proportioned limbs. Though they do not exhibit pro~ minent and athletic muscles, and their arms are rather like those of a well made woman, they g zave proofs of very great strength. They ornament themselves in the most romantic manner. Many of them have a circle of feathers around their head, or of swine’s teeth strung on a cord, on their toes and fingers ; feathers, or small bunches of uae hair, and other kinds Se ornaments, around their neck. Most of them are more or less tatooed. The figures are regular, and have each a determinate name: come of them are attended with particular privileges; thus, for example, the Englishman had a figure en his breast which gave him a ‘right, on certain testiva ls, to form part of Ketenue’s suite. T hose who have not this mark are not entitled to receive any pork. Some of the officers and most of the sailors on board our ship caused themselves to be tatooed. The natives, for the most part, go entirely naked. Their chief food is the bread-frait, which to me did not 2ppear to be very savoury; but jt was then unripe, and not in season. The tree has a good deal of similarity to the wild chesnut tree. They eat also bananas, coco- shed yams, pork, fish, and even human flesh. However incredulous I was in regard to the last potmt, it is certain that these people, w ho according to every appearance are so friendly and so mild, are real cannibals. The Englishman, and afterwards the Frenchman, who ‘certainly! had not entered ito an agreement to deceive us, concurred fully in their ace counts ef this circumstance. We haye several sculls, two- ef which I purchased, which were those of enemies whom they had defeated in battle and afterwards eaten. Some years, when the bread-fruit is scarce, a famine takes place: and on such occasions many of them kill ‘their wives or children, and eat them; others undertake a warlike expedi-- tion against the enemy 3 that is to say, several of them ereep imperceptibly in the night-time to the neighbourhood of the houses ef the enemy, or conceal themselves behind trees or among the grass, and as soon as they discover any of the enemy, whether men, women, or children, they immediately attack them , carry them off, and devour them. Even when there is no "scarcity, their expeditions against the enemy are continued, partly because they delight in them, and partly because they consider human flesh as a reat delicacy, and prefer it to that of their hogs. They fight also battles in which one party is regularly pitched arainst another. Their w eapons are slings, lances, and clubs. The two last are made of casuarino wood :. one of these Russian Expedition to Japan. 11 these clubs I have in my possession. As soon as a couple of the enemy have fallen, the battle immediately ceases, because something has been obtained to eat. The English- man, Roberts, cautioned us not to place any confidence in these islanders ; to be always on our guard, and, when any _of them offended us, to shoot them immediately : he assured us that this would produce no bad consequences, and that the rest would give themselves no trouble about it. Such are the islanders of the South Seas, so celebrated for their mildness and humanity! On the most friendly of these islands they are no better; and Cook, after being massa- cred, was publicly eaten by the natives of the Sandwich isles : nothing is clearer, notwithstanding the pains which capt. King and M. Fleurieu have taken to contradict it. It is mere folly to consider the man of nature, as he is called, as better and more benevolent than the man who has been civilized. Fortunately we had uno disagreeable disputes with them. They feared us on account of our fire-arms, and considered us as atuas, or gods. None of them were ever struck by our shot, though we sometimes fired muskets or some of our cannon in the night-time, to frighten those whom we heard swimming around us, and to prevent them from injuring our cable. These islanders spend their time properly in a state of indolence, and employ themselves only in dancing or or- namenting their persons. Wehen any of them set about making tackle for catching fish, a girdle, or club, the work is speedily completed. On the whole, none of them, pro- perly speaking, have any particular occupation. When we gave any of them work to perform, it was a kind of festival tothem. They dragged away for us the wood which we had cut down; but they were most useful to us in filling our water casks. I do not know how other navigators coul’ convey, without their assistance, large casks through the violent breakers ; but it required five or six of our sailors to accomplish what one of these natives could do secminely in sport. When a large wave came and _threatetied to dash the cask and man to picces on the shore, the latter dived ‘into the water, forcing down the cask along with him, so that the wave passed ‘over both; after which the islander swam on quietly as before: on the approach of the next wave he did the same; and before we could believe it pos- sible he arrived with the cask at our boat. The piece of iron which he obtained as a reward for this service he showed with a great deal of laughter to his companions standing on the shore, who then burst out into loud laughter 1 also, 12 Russian Expedition to Japan. also. ‘They are remarkably fond of dancing, which forms the principal part of all their festivals. The most essential part of their dancing consists In a quivering motion of the hands: it is not disagreeable, and has in it something sin- gular, which to me at least was new. Their music consists in beating in time with the right hand on the Jeft arm. The sound was much louder than we were able to produce in the same manner. When they sing, they clap their hands in time in such a manner that the fingers cross each other and produce a full tone. A drum made of fish-skin was used also on these dancing festivals. Their morals ave of a piece with the rest. Parents and husbands sent their daughters and wives on board our ship to display their charms; and a piece of iron ora nail was sufficient to remove all their scruples. Those who have wives keep also a fire-maker, because this business is some- what Jaborious. This fire-maker is the woman’s second husband, and he pays great attention to her because his own interest is interwoven with hers. I was told afterwards by the Frenchman that the men are very jealous. This seems to be acontradiction, but it may nevertheless be explained. Their expertness in swimming is really wonderful. Many of them swam off early in the morning to the ship, with their forenoon’s repast, consisting of coco-nuts, which they ate in the water, and returned on shore late in the evening. Others had both their hands full of different arti- cles, which they wished to barter wit us, or which they had procured from us. These they held up, and swam for several hours merely with their feet. Some of them, for the greater convenience, had a piece of hoard with them. This board they held before them, and suffered themselves to be driven on shore by the surf: however dangerofs this experiment may appear, none of them ever experienced any hurt by it. : ' Taaboo is the magic word here, in which are comprehended all their religious, political, and moral laws. Buta clearer idea of the importance of this word will be conveyed by a few examples. When one says that this or that place is dedicated tu the spirit of his father, the spirit Atua mhabits © the place, and no person dares to pass over it; it is teaboo. When a person gives his name to a tree or to any other man, the tree or man is taaboo-to all others: the spirit resides in both. Jn all the houses the place set apart for eating 1s taaboo to the women; and when any of the na- tives have got any thing which they are desirous to eat un- molested, they sit down im the place which is- taaboo. Swine’s Russian Expedition to Japan. i3 Swine’s flesh is ¢aaloo to the women; but they eat human flesh when it is given to them, Ketenue and his whole fa- mily were ¢aaloo: those who bore Ketenue’s name were taaboo. Vhe.case was the same with the Englishman; so that ho one durst do him any hurt. There ts a particular ceremony by which people can make themselves taaboo. It consists in binding feathers around the head, dancing and singing, and declaring that they desire to have Ketenue’s name. While this ceremony lasts, they are safe from all harm. One day it was ¢aahoo for all the islanders to come on board the ship, those only who brought hogs to the ship were excepted, Those who break taaboo wil! be eaten on the first opportunity by the enemy. This they so firmly believe, that it keeps them in order. When it is discovered that any one has broken taaboo, he must make atonement for his fault by giving presents, such as hogs, &c. which the priest applies to his own use; or he is deprived of his land: if he has nothing, he becomes kzkino; he is then unprotected, and always in danger of being eaten by the enemy. Tapeka Ketenue is said to possess a great deal of land; he does not go to war, but there is nothing to prevent him if he chooses it. In times of scarcity be maintains a great many of the natives ; for, as he possesses abundance of bread- fruit trees, he has large pits filled with fermented. bread- fruit, which in this state will keep a long time. I cannot say much in favour of this kind of food; it has a disgust- ing sour smell, similar to that of fermenting. wheat used’ for manufacturing starch.. He has no power to command any person, but he and his family are taahoo; and as he is able to give maintenance to a great-many, for the sea be- longs to him, and all those who fish in it must bring him part of what they catch, he is still an important personage. He has also several houses. Roberts, who was well esta- blished, had received from him a house with coco-nut and bread-fruit trees.” [To be continued] Ji. Some [4] II. Some Accoint of a terrible Hurricane which legan te the Windward of the Caribbee Islands on the 3d of Sep- temlcr 1804, and proceeded North-westwardly over thé Virgin Islands and Bahamas on the 4th, 5th, and:6th, until it reached Florida, Georgia, dnd South Carolina, on the 7th, 8th, and 9th; and of a furious Gale from the North-east which prevailed at the same time, ard pro- ceeded South-westwardly until it met the former: show- ing that Storms of the most destructive Violence some- times arise to Windward, and bear down every Thirig be- fore them in their Passage to Leeward: To Mr. Tilloch: DEAR SIR, New York, April 2, 1805. INCLOSE you a copy of my letter to baron Humboldt on the hurricane of September 1804. It is intended to furnish facts for a more satisfactory theory of the American winds than we possess at present. My situation at Washington, the seat of our national government, and the great amount of ship news contained in our gazettes; have enabled me to make the collection of facts very extensive. Yours truly and respectfully, SAMUEL L. MircHItt. Mr. Volney, when he was in North America, sought information concerning its atmosphere, with an intention of forming a theory of the winds prevalent in the territory of the United States. At that time I was not able to furnish any facts worthy to be communicated to that able observer. Since his return to Europe I have had an excellent oppor-~ tunity to collect the facts afforded by a most violent snow storm from the north-east, on the 21st, 22d, and 23d days of February 1802. These were published in the first Hex- ade, vol. v. p. 465, of the Medical Repository. From that inquiry it appeared that our most boisterous winter storms, accompanied with snow and a north-east wind, began to lceward, and progressed to windward from South Carolina to Maine, at the rate of about one hundred miles in an hour. Since that collection of facts was printed, Mr. Volney has given to the public “ his Picture of the Climate and Soil of the United States,’’ in two octavo volumes, at Paris, in 1803. In the ninth chapter of this work he has vén- tured to give “a system of the winds within the United States.” Herein he has treated of the winds from the north, north-east, and east ; from the south-east and south; from Account of a Hurricane in the West Indies. 13 from the south-west; and from the north-west, in distinct sections. But finding there are some considerations in my piece on the gale of February 1802 which are not centained in his treatise upon our north-east wind, [ take the present opportunity of mscrihing it to you. In his short essay upon the south-east wind he closes his observations, for want of more facts, not choosing to supply their place by conjec- ture. I believe that, by reason of a hurricane which lately © happened in the southern latitudes, bordering on countries in North and South America which you have visited, it is now in my power to communicate to you some additional facts on the south-east wind of the western hemisphere, and some very important information relative to its north- east and east winds. Between the 3d and 9th of September 1804, there oc- eurred in the Caribbee Islands, in the Bahamas, on the ocean to the north-east of these, and on the coasts of Fle- rida, Georgia, and South Carolina, one of the most de- structive storms that had ever raged within the memory of man. The agitation of the atmosphere and of the sea was so dreadful as to overwhelm and destroy an uncommon number of vessels, cargoes, and crews, both on the ocean and in port, and also to work great damage on shore. A current from the south-east swept all before it in its pro- gress from the’Caribbees. It had, however, various turn- ings, whirlings, and eddies, blowing in the most opposite directions, aud veering almost all round the compass. An- other current from the north-east met the former in about the latitude of Charleston or Beaufort. The two streams formed for a while an east wmd, which continued until the south-east gale triumphed by its superior force. This con- flict of the winds was accompanied by torrents of rain, bv a retardation of the Gulf Stream, and by such an accumu- Jation of water in the curvature of the coast between Florida and North Carolina, as to lay a great portion of the low zhores and islands of Georgia and South Carolina under water. This storm, unlike the former one which I de- scribed, began to windward, and by violent propulsive force worked its way to leeward. I have reduced to something like method, the relations and facts as stated by navigators, and gathered from cotemporaneous publications. A gale or hurricane of this sort happened in September 1782, as far north as lat. 42° 15’, and in Jong. 48° 55’. I¢ began on the 16th, and destroyed many fnalich’shipa, be- longing to a fleet of ninety sail, then off the banks of New- foundland, and hound homewards from Jamaica. It began at 16 Account of a Hurricane at east-south-east on that day, and prevailed with greater violence than was ever before known on that part of the ocean, until about three o’clock the next morning, when, without the least warning, it shifted m an instant, and blew with such fury from north-north-west, that the oldest sea- man in the fleet had never seen the like. The Ramillies, the Centaur, L’Hector, the Ville de Paris, and many other ships, the spoils of Rodney’s victory m the West Indies, ail perished. The particular accounts will be given under distinct heads, classing the occurrences according to their appearance. Ist, In the Caribbee Islands.—On the 3d of September there was a hard gale at Martinique, so as to make vessels — quit their anchors, drive ashore, &c. A number of vessels were driven ashore at St. Croix. Of thirty-two sail at St. Bartholomew’s, only two rode it out. At St. Pierre’s (Martinique), Mr. J. Anderson stated the wind to have been from the north-west and west-north-west. . At St. Bartho- lomew’s it began from the north-west, then blew from north, and at last got round to the south-west. On the ad, 4th, and 5th of September, capt. Henry, on a voyage from Point-Petre to Philadelphia, was obliged to he-to under Deseada for fifty-six hours. The gale was heavy, with rain and thick weather. ; 5 Captain Jones related that at Potat-Petre there was, on the 4th of September, the most dreadiul gale known for - twenty years. There happened to be no vessels at Basse- terre. But at Dominique every vessel had been lost. On the 4th of September two brigs, commanded by cap- tains Lovell and Glazier, were driven out of their ports ; one at St. Croix, and the other at St. Thomas. The gale was so violent as to make them slip their cables with the loss of their. best bowers. It lasted thirty-six hours, and was as severe as any ever recollected. At St. Thomas thirty sail were driven on shore. _ Capt. Smith sailed from Demarara on the 21st of Au- gust, bound for New York. He was overtaken by the hur- ricane on the 4th of September. It blew from the south- ward and eastward. Atter being thrown on his beam ends, and losing his foremast and bowsprit, she was rendered so leaky as to be abandoned on the 8th as a wreck. * Capt. Boardman, on his passage from Guadaloupe te Newbury Port, experienced the gale from the 4th to the 7th of September. Capt. Day, on his passage from Ber- bice to the-same place, was overtaken by, the gale to the leeward of Tobago. ait % — Capt, in the West Indies in Sept. 1804. 17 Capt. Mountfort, from Demarara, gave information that the hurricane had not been felt there. Capt. Wood declared the like of Grenada. The gale commenced at St. Thomas on the 4th of Sep- tember, in the afternoon, and lasted three days. During this time it destroyed forty-two sail of vessels. Accounts from the windward stated that the British packet from Fal- mouth to Barbadoes had been lost. Guadaloupe, St. Bar- tholomew’s (where thirty sail were driven on shore), Tor- tola, St. Kitts, Antigua (four sail driven on shore, a packet foundered at anchor, and much damage done to estates in the mountains), Eustatia, St. Martin’s; and, in short, ali the Caribbee Islands experienced a like fate, with the loss of many vessels, and much other property. ‘There were four wrecks at Anegado. At St. Kitts the hurricane began on the afternoon of the 3d of September. It blew at first from the north and north- west. On the 4th it shifted to the south-west, and changed frequently to the south, blowing with equal fury in all these directions. It was reckoned ‘to be nearly as fatal in its ef- fects, to shipping and to property on shore, as the ever- memorable one in 1772, and of inuch longer duration. The quantity of rain which fell was great and sudden, so as al- most to deluge the mountains. 2d, In the Bahama Islands.—The gale was experienced at Turks Islands on the 4th of September. It prevailed in the Bahamas with extreme violence. No severer one was ever known. At Turks Islands all the vessels ran ashore except two, which put to sea. Most of them were totally lost. Capt. Rhodes, who put to sea, returned thither on the third day after, having sustained no other damage than the loss of one of his boats. The sea had broken into the salt-ponds, injured the dykes and canals, and melted large parcels of the salt in stacks. But capt. Waite informed us that the gale was severely felt at Nassau, in New Providence, on the 5th and 6th of Sep- tember. About thirty sail of small cratt were driven on shore, but not much damage done to square-rigged vessels. Capt. Bakus, who was on his passage from Ragged island to New Providence, experienced the gale on the 7th. The wind came first from north-east, then hauled to the west, _and afterwards blew north-north-west, and then west again. - 3d, On the Atlantic Ocean, to the North-east and North of the Bahamus.—Capt. Johnson encountered the gale on the 6th of September, in lat. 31° 5’, and long. 81°. It first blew from the north-east, and from that veered to west- Vol. 22. No. $5, June 1805. B south 18 Account of a Hurricane south-west, north-west, and south-west. It was terribly furious, so as to damage his rigging very much, loosen his masts, and render his ship very leaky. Capt. King, from Demarara; was invaded by the gale on the evening of the 6th, in lat. 21° 51’, and his vessel was thrown on her beam ends. He was forced to cut away her main-mast. Lost aman, who was washed overboard. Capt. Messroon took the gale in the Gulf Stream, lat. 20°, on the 6th of September. The wind was then east- north-east, and continued so until the 7th, then it shifted to south-east. It was very sevcre, though he escaped with- out material damage. In lat. 22°, long. 64°, capt. Beard was wrecked in the gale. It began on the 3d of September, continued during the 4th, and did not end before the 5th. He and his crew were taken off the wreck on the gth. -On the 7th, 8th, and 9th of September, capt. Jenne, bound from Kingston, in Jamaica, to Baltimore, suffered a tremendous gale in lat. 33°, long. 74°. The wind varied between north-east and south-east. Capt. Mood, on a voyage from Alexandria (Virginia), to St. Mary’s (Georgia), was, on the night of the 7th, in the Gulf Stream, to the eastward of Charlston: the wind there was east-north-east, and so hard as to throw his vessel on her beam ends. She lay several hours in this situation. Several of his crew were washed overboard. . ; Capt. Miller, on a voyage from Martha-Brae, in Jamaica, oound for Wilmington (North Carolina), experienced the same gale the same night, on the inner edge of the Gulf Stream. It was so violent as to heave his vessel on her, side as she was lying-to under her jib, to unstep her masts, and to tear up her deck. In this forlorn condition the crew were fortunate enough to save themselves by gettting on board another vessel. Capt. Andrews, on his way from Charlston to Nassau (New Providence), encountered the most formidable part of the gale on the night of the 7th of September, in lat. 26°, long. 77°. She was thrown on her beam ends, her boom broken io pieces, her main-topsail and rigging carried away, and two men washed overboard. The brig Augusta was on her passage from Savannah to New York when the gale began. She had sailed on the~ 3ist of August, and had progressed no further than the Frying-pan Shoals, off Cape Fear, on September 7th. Being there exposed to its vehemence, they stood off shore as long as she could carry sail ; but at half past two P, M, they were obliged in the West Indies in Sept. 1804. 19 obliged to lie-to. The weather was turbulent all the night. On the morning of the sth the rage of the storm was ex- cessive, beyond what any person on board had ever expe- rienced: It increased until two P.M., and continued all night with unabated fury. At day-light on the uth she was about three and one-half leagues from the breakers on the Roman shoals at Cape Carteret. They were lucky enough to escape these, and to arrive about noon at Charleston bar, which was one continued breaker, so that -no pilot could get out. -They were forced to cast anchor cna lee shore, and with the help of two cables and anchors rode it out until the 10th, when she got into Charleston. Capt. Davidson, of this vessel, related, that in the fore part of the 7th, before the gale began, he plainly saw a brilliant star in the zenith. 4th, In the Latitudes South of the Bahamas.—Capt. Jag- gart, who left Jeremie, in St. Domingo, on the 14th of September, declared, that the gale was not felt or known at that place at all. The captain of a Spanish schooner from Matanzes said, the gale was felt there, but not much damage done. The British armed ships Theseus and L’Hercule took the gale first in north lat. 22° 19’, and west long. 63° 44’, on Wednesday, September 5, about eight o’clock P.M. They were then about sixty miles north-east of the Square Handkerchief,” and about one hundred miles north of the “© Silver Quays.”’ The gale was in the beginning from the north-east, and by degrees came round to the south-east. Its violence reduced them to the utmost distress. It lasted until Friday the 7th, at five P.M. They afterwards got into Kingston harbour, in the island of Jamaica. Capt. Howe, from Porto-Rico, related, that the gale was experienced there on the 4th of September, and drove ashore every vessel at the west end. Capt. Bennet sailed from St. Thomas on September 3. On the 6th, about thirty miles southward of Porto-Rico, he was assailed by a tremendous hurricane. The wind was south-south-east, but frequently varying. The Jamaica papers of the sth contained accounts of considerable da- mage done on the south-east side of that island by the gale of the 4th. ‘The north side did not feel it. 5th, In the Latitwles North of Cape Fear.—It appears that the gale did not prevail much to the northward of Wilmington (North Carolina). {It was but slightly felt there. On the gth, a small schooner and periago were driven on shore, but not materially injured. Ba The 20 Account of a Hurricane The brig Wilmington packet, from New York, had been ashore on the Frying-pan, but, after taking out the cargo, was got off. The crops in the neighbourhood of Wil- mington had not been injured. . Capt. Tilford, on a voyage from London to Baltimore, felt the gale on the 3d of September in lat. 39°, and long. 65°; it blew from east-north-east, and continued in the form of a strong and favourable wind until the sth, when he made the Capes of Chesapeake. As soon as. the gale reached land it grew more violent, and seems to have parted into two streams. By the assistance of one he then ran up the bay to the mouth of Patapsco im twenty hours. The other branch turned southward along the land toward Cape Hatteras. Vessels from Europe, which had not got further south than lat. 39°, seemed to have escaped the hurricane. 6th, On the Continent of North America, and the adjacent Islands. —(A) In Florida the gale was excessively bard; at St. Augustine the tide rose to an uncommon height. Of nine vessels in the harbour only one rode out the storm. (B) In Georgia. ‘At Savannah the gale began on Satur- day morning the 8th. The wind was from the east, yet varying between south-east and north-east incessantly. It was more dreadful than any that is recollected to have ever happened there. It commenced by slight wind and rain until about ten A. M., when it blew with uncommon vior lence. It was accompanied by heavy rain, and went on increasing until between six and seven in the evening. It did not cease until three o’clock in the morning of the gth. The continuance was seventeen hours. The water rose to between eight and ten feet above the level of common spring tides. Houses and stores were blown down by the wind, and undermined by the water. Fences and trees were pro- strated. Ships and vessels were stranded, and left high and dry upon the tops of the wharves. Great damage was done on the island opposite the town, and on Wilmington and Skidawa Islands. Fort Green, on Cockspur Island, was completely levelled; thirteen lives were lost, and all the buildings destroyed. The watcr was supposed to have risen from fifteen to twenty fect above the level of the fort. The surface of the land was considerably lowered and washed away. Qne of the national gun-boats was carried about eight miles from her moorings, and landed in a corn-field upon Whitemarsh Island. A cannon weighing 4,800 |b. was carried thirty or forty feet from its position. A bar of lead of 300/b. was carried one hundred feet. Cases of 7 ’ cannister in the West Indies in Sept. .1804. 21 eannister shot were carried from one hundred, to two hun- dred feet, and muskets were scattered all over the island. Such was the beating of the ocean against the shores, that at Savannah the rain which fell was of a saline taste. An experiment made by evaporating some of it, proved it to be highly wapreenated with sea salt; this was probably de- rived from the spray of the sca. The water in the river was saliish at Savannah, and for fifteen miles above. Sand was blown into the upper stories of houses thirty feet higher than the surface of the earth. At Si. Simon’s Island great damage was done by inun- dating the crops and drowning the negroes. The like hap- pened on St. Catharine’s, and on the other islands along the coast. At Sunbury the bluff was reduced to a perfect beach, and almost every chimney was levelled with the ground Mr. [saac Briggs, who was im the interior of Georgia, about twenty-three miles from the high shoals of Apalacty, on his way to Hawkins’s settlement, on Tallapoosa river, arrived at the house of an Indian trader there on the 8th of Sepiember: here he was detained two days by severe stormy weather. In his letter to Mr. Jefferson he remarks, * that sometimes his ear could scarce distinguish an interval be- tween the sound of one falling tree and that of another.” The wind was north-east. The gale was distinctly felt in the upper country as far as it is settled, which is to the distance of three hundred miles from the ocean. It was felt there as a strong wind which blew down the corn, but was not hard enough to prostrate trees. There it blew from the north-east, and began on the afternoon of Saturday the Sth. The rain did not beyin unul in the evening. (C). fn South Carolina.—At Charleston the gale was more furious and long continued than was ever known since the hurricane of 1752. It prevailed there on the 7th, 8th, and 9th of September, and exceeded, in violence and duration, the great storm of 1783. It began at Charleston on the 7th, about eleven P. M., and continued until Sunday morning, the gth, at one. The wind was at first north-east. In the course of the morning of the 8th it shifted to the east, and in the afternoon to south-east. It lasted for nearly thirty-six hours. But three or four of the vessels in the harbour escaped without injury. Many were much damayed, and several wholly lost. The whole of the wharves, from Gadsden’s, on Cooper River, to the extent of South Bay, received considerable damage. Many stores B3 were 22 Account of a Hurricane were washed or blown down, and much property lost. Numerous houses were unroofed, and trees overturned. On Sullivan’s Island fifteen or twenty houses were un- dermined by the water, and carried away. Fort Johnson, which had been long in a tottering condition, was destroyed, so as not to admit the mounting a single cannon. The breast-work and pallisadoes of Fort Pinckney were washed away. From Fort Moultrie, near which the sea made a clear breach to the cove, every spot was covered with water. _At Jacksonburgh the crops of corn and cotton were much injured. The bridges were carried away between Charleston and George Town, and so many trees blown across the roads as to obstruct the stages for several days. At May River all the crops, cotton, and negro houses, machines, &c. were completely swept off. The tide rose nine feet higher than the highest spring rise. On Hutchin- son’s Island many negroes, and some white people, were drowned. The like happened at Dawfousky and Brough- ton’s Islands. At Coosahatchie trees were thrown across the roads, - and bridges carried away, so as to prevent intercourse through the country; that village was entirely surrounded by sea water. In Prince William’s parish, Beaufort di- strict, the storm was experienced in an awful manner. The sea formed a junction through the streams of Pocota- ligo, Stony Creek, and Huspa rivers, in such a manner as to turn Scotch Neck into an island. Through the fields, at Sheldon to Motley, the water covered the plantations four feet deep on the high road and causeway leading to the meeting-house, rendering the roads impassable. Great de- struction was made upon the crops of rice and cotton, and many animals of various kinds were drowned. Nothing but the high ground was visible on the roads of the Fish- pond and Horse-shoe savannas. The gale began at George Town (South Carolina), be- tween three and four A.M. on the 8th of September. The wind was at north-east, and blew with increasing violence until midnight. It then changed to south-south-east, and abated little of its fury before the evening of the gth. The rain descended in most profuse quantity the greater part of the time. The gale extended to the upper part of the country as far as the mountains, to a distance of two hundred and fifty miles. It blew from the north-east, and was so violent at one hundred miles from the sea board, as to blow down forest in the West Indies in Sept. 1804. 23 forest trees in great numbers, so as to render the roads im- passable for carriages. . From a consideration of all these détails it appears that the gale extended from beyond the latitude of Tobago, in 12° north, to the latitude of Wilmington (North Carolina), northward of lat. 34°, sweeping a tract of ocean at least twenty-two degrees in extent. It probably exceeded by far these limits, as capt. Tilford felt it as far north as 39°. It appears also that it reached from the longitude of the wind- ward islands, in 60° west of Greenwich, to the meuntains and back settlements, travelling over a surface of as many degrees in that direction. And its prevalence was, in all likelihood, much more wide and diffusivé than has come to my knowledge. The gale in the islands blew from north-north-west, and even from the south-west, but, as it approached the coast, got round to the eastward, and varied between north-east, east, and south-east. Jt arose to windward in both the north-eastern and south-eastern quarters. In this respect it widely differed from the great north-east snow storm de- scribed in Med. Rep. Hex. i. vol. 5. p. 465, which began to leeward *. It seems to have taken about four days for the * So did the one which is described in the following account :—But these snow storms from the north-east do not seem always to blow the whole length of the coast between the Gulf of St. Lawrence and the Bay of Mexico. ‘The winter of 1804-5 was the most rigorous that had happened since that of 1779-80. One of the snow storms which occurred during the latter winter, illustrates at once the fact of their beginning to leeward, and of their limited extent in certain cases. It also shows that they prévail at different places with very different degrees cf violence. ‘he weather had been intensely cold during January; the quicksilver had sometimes been as low as $° above 0, and frequently down to 11 and 14°. After this uncommonly severe weather, the atmosphere rapidly became warmer, the mercury rose to 469 in the course of a few days, and immediatelya thick and heavy fog overspread the ice on the rivers, and the snow on the earth. ‘Chis continued until the 26th, when the cold increased again. About four in the afternoon of that day, snow fell at Washington, and there was a mingled fall of snow and rain at George Town (Maryland). ‘This storm was felt at New York city in the fore part of the evening, and not until eight P.M. by the ship Favourite, then off Boston harbour. At Newbury port the newspapers state it to have begun on Sunday morning, the 27th. By a comparison of the facts it will be found that this storm began at least four hours sooner on the Potowmac than in Boston harbour. ‘The difference of time was no less remarkable on its cessation; for it had ceased so entirely at Washington on Sunday night, that the weather had cleared up on Monday morning the 28th. In New York it continued until Tucsday morning, and lasted at Boston until ‘Tuesday evening. Though the storm was not of long duration at Washington, and the fall of snow was moderate there, yet it was far otherwise in New York and Massachusetts. ‘Vhe quantity of snow which fell in both those places was uncommonly great. Many vessels were wrecked and lost on the coast B4 of £4 Hurricane in the West Indies in Sept. 1804. the south-east current (from the 3d to the 7th) to force its way along from !obago and Barbadoes to Augustine, Sa- vannah, and Charieston. In hke manner, by comparing the ‘imcs of its commenccment along the Fredish coast, it js evident that the north-east current blew violentiy near the Fryicg-pan shoals at half past two P.M. on the 7th; that it began at Charleston at eleven the same night, and did not become formidavle at Savannah before ten in the morning of the sih, consequently it did not begin at Charlesion until eight hours and a half after it began at the Frying-pan, nor at Savannah sooner than the nine- teenth hour ad a half subsequent to its commencement at the same place. Hence, on comparing this storm with the one before alluded to, it is evident that this, which had its rise to windward, was not near so rapid in its progress as that one which took its origin to leeward. From all these facts and considerations there is reason to believe, that this gale, consisting chiefly, as it advanced toward the Continent, of currents from the north-east, east, and south-east, was the trade-wind diverted from its ordi- nary course, and blowing with a force prodigiously aug mented over a tract considerably to the northward of its usual limits. The two columns of agitated atmosphere moving obliquely toward each other, appear to have met and expended their combined forces upon that bend of the coast which forms the front of North Florida, Georgia, and South Carolina. At present I know too little of atmo- spheric movements to determine what was the particular rarefying or expanding cause that, on this occasion, put the windward.air into such destructive commotion, made it rush with such resistless impetuosity to leeward, and more particularly determined it to quit the intra-tropical regions, and exert its whole strength upon a part of the Continent so far to the northward as that which lies be- tween St. Augutine and Wilmington, betwixt the latitudes of 29° and 34° north. of Massachusetts in particular; and in the latter, this snow storm from the north-east lasted thrice twenty-four hours, white in Maryland it did not at furthest continue more than half the time, and certainly with less by far than half the violence. NT. Twenty- [ 25 j III. Twenty-second Communication from Dr. TaornTon relutive to Pneumatic Medicine. To Mr. Tilloch. Case of Consumption cured by Hydro-axotic Gas. June 18, 1805, No. 1, Hinde-street, Manchester-square. Weax HucueEs, ext. 18, helper to Mr. Cozens, livery stable keeper, City Arms, London-street, had all the marked symptoms of a decline. He had a very bad cough; used in 24 hours to spit up near half a pint of discoloured mat- ter; had colliquative sweats; hectic fever; great debility: appetite good, and yet reduced in flesh to a mere shadow. These strong criterions of consumption had been progres- sively increasing for more than half a year, when he applied to me for advice. I pursued in this case the same plan as had saved Mr. Gregory, of Berners-street *, viz. the in- balation of hydro-azotic gas, with tonic medicines ; and in two months all these alarming symptoms vanished, and the lad was restored to health. Observations on this Case by Dr. Thornton. 1. Consumption is deemed a fatal disease ; and the prac- tice universally pursued in England has rendered it, I be- lieve, still more destructive. 2. in Dr. Rush’s works, the able professor of Medicine in Philadelphia, the best plan of treatment is laid down. 3. Bark-(at witich our practitioners are so alarmed) 1s re- commended, with other tonic medicines. 4. Consumption must be considered either as a defluxion of the lungs, or as an abscess, or ulceration thereof. 5. If a defluxion, as in other gleets, bark is advisable: if ulceration, the treatment of the constitution should be as in other wounds.—Bark is there universally recommended. 6. Dr. Rush has recorded some cases where persons shot through the lungs have recovered. Captain Christie, of Liverpool, lately applied to me for advice. In a sharp en- gagement with the French, a ball entered the sternum, and lodged under the scapula. The wound in the lungs healed, and he felt aiterwards only ‘debility from the great loss of blood sustained. 7. The objection against bark, myrrh, and wine, is the cough. Colds are, I contess, aggravated by such treatment, * This cure is recorded in Number 13 of our Magazine, p. 95. 7. The 26 On the Action of and the incipient stage of phthisis; but in the subsequent stages the only chance is, I speak from wide experience, the practice I have here recommended. 8. Inflammation of the lungs is prevented by the hydro- azotic gas. The lad is now before me; is fat, looks well, and has been cured a twelvemonth. IV. On the Action of Platina and Mercury upon each other. By RicHarD CHENEVIX, Esq. F.R.S. M.R.EA. Fe, Freyberg, June 3, 1804, Ox the 12th of May 1803, I had the honour of presenting a paper to the Royal Society, the object of which was to discover the nature of palladium, a substance just then an- nounced to the public as a new simple metal. The experi- ments which I had made for this purpose led me to conclude that palladium was not what it had been stated to be, but that it was a compound of platina and mercury. It was natural to suppose that a subject so likely to spread its influence throughout the whole domain of chemistry, and which tended even to the subversion of some of its ele- ments, would awaken the attention of philosophers. We find accordingly, that it has become a subject of inquiry in England, France, and Germany ; but the experiments which I had recommended as the least likely to fail, have been found insufficient to insure the principal result; and I have had the mortification to learn that they have been generally unsuccessful. JI have even reason to believe that the nature of palladium is still considered by chemists, at least with a very few exceptions, as unascertained ; and that the fixation of mercury by platina is by many regarded as visionary. The first doubts were manifested in England; and Dr. Wollaston very early denied the accuracy of my inquiries. But as he has not published his experiments, I have had no opportunity of discussing them. His opinion, however, must have such weight in the learned world, that I should ~ have neglected a material fact in the history of palladium if I had not mentioned it in this place. | In France the compound nature of palladium has been more generally credited. "When the National Institute was informed of my experiments, a report was “ordered to be * From the Transactions of the Royal Society for 1805. ’ made Platina and Mercury upon each other. 27 made upon them, and M. Guyton was the person appointed for the purpose. He repeated some of the experiments, and -produced some of his results. His general conclusion was the same as mine. Messrs. Vauquelin and Fourcroy then undertook the sub- ject, and they were led by it to the confirmation of the re- cent discovery of M. Descotils. The existence of a new metal which that chemist had found in crude platina, re- ceived great sanction from their experiments ; and thus the discussion upon palladium has established a fact which will be considered as interesting, but which would be much more so, were we not already overburthened with substances which our present ignorance obliges us to acknowledge as simple. No sooner were these celebrated chemists convinced of the existence of a new metal in platina, than they concluded that it must play a principal part in the composition of pal- Jadium. Shortly after this, in a note to a letter from’ M. Proust to M. Vauquelin, in which M. Proust expresses his astonishment concerning all he has read upon palladium, Messrs. Fourcroy and Vanquelin further declare, as their opinion, that this compound metal does not contain mer- cury, but is formed of platina and the new metal. Whe- ther this new substance does or does not play a principal part in the formation of palladium, could not be ascertained at the time my experiments were made, because the new metal itself was not then known. But from all that Messrs. Fourcroy and Vauquelin have stated, in such of their dif- ferent memoirs upon this s:tbject as I have seen, the grounds of their supposition have not appeared. May we not refer their opinion, then, to that common propensity of the mind, against which M. Fourcroy has himself warned us with equal justness and eloquence on another occasion, namely, a proneness to be allured by novelty beyond the bounds of rational belief, and to convert principles which are new into principles of universal influence. Messrs. Rose and Gehlen* were the first among the German chemists who instituted. experiments upon palla- dium; and M. Richter has also published a paper on the same subject. The first attempt of Messrs. Rose and Gehlen to form palladium was by the precipitation of a mixed solution of platina and mercury by green sulphate of iron. Their re * Neues Algemeines Journal der Chemie herausgegelen von Hermstadt, Klap- roth, Richter, Scherer, Tromsdorf, und Gehlen. Ersten Landes funftes heft. 6 sult \ 25 ‘On the Action of sult was precisely that which I had observed when my ope- rations failed altogether, aud which of course was the most frequent. This method “was repeated twice. The second time the precipitate of platina and mercury was boiled with muriatic acid, in order to free it from iron; but the latter trial was not more successful than the former. Their third experiment was what they have called a re- petition of that in which I bad obtained palladium by pass~ ing a current of sulphuretied hydrogen gas through a mixed solution’ of platina and mercury. Their method was the following :—They dissolved 150 grains of platina with 450 of mercury, and added a solution of hvdro-sulphuret of potash. They obtained a precipitate which, at first, was black, afterwards gray; but the whole became black by being stirred. To be certain that all the metal was preci- pitated, they added an excess of sulphuret of potash, and perceived that a part of the precipitate was redissolved. The liquor was then filtered, and to that part of it which con- tained the redissolved precipitate an acid was added. From this process they obtained a yellow precipitate weighing 91 grains ; and 50 grains of this, exposed to a strong heat, left 3-Sths of a grain of platina. They obtained no palla- diem from that part of the precipitate which had not been redissolved ; and the result of the experiment was complete failure. I shall not make any observation upon the issue of this process, since, in this case, the best conducted is but too liable to be unsuccessful, and that without any apparent fault in the operator. But as it has been given as a repeti- tion of one ot mine, 1t may not be fruitless to examine how far the repetition was exact. I had passed a current of sulphuretted hydrogen gas through a mixed solution of platina and mercury, by which means they were precipitated together. My object was so nitimately to combine sulphur with these metals, that when exposed to heat they might (if I may be allowed the ex- pression) be in chemical contact with it at the moment of their nascent metallic state; and as a low temperature suf- fices, as well to reduce those metals as to combine palla- dium with sulphur, I hoped that those effects might be produced before the total dissipation of the mercury. How far my expectation was fulfilled has been stated m my former paper. The sulphuretted hydrogen gas which Mersrs. Rose and Gehlen presented to those metals was combined with pot- ash. Now, in the course of docimastic lectures annually delivered Platina and Mercury upon each other. a) delivered by M. Vauquelin at the Ecole des Mines in Paris, when he was professor at that establishment, it was his constant custom to exhibit an experiment to prove that mercury, precipitated from its solution by many of the al- kaline and earthy hydro-sulphurets, was redissolved by adding an excess of them. It is moreover well known that there is a strong affinity between potash and the oxide of platina, and also that when those substances are brought together in solution, a triple salt, but little soluble, is the result. It was to avoid these difficulties that I had employed uncombined sulphuretted hydrogen gas; for the method adopted by Messrs. Rose and Gehlen appearing to me to be the application of two divellent forces, J] presumed that it would produce a sepa~ ration. The result of their experiment, which, it appears from their paper, they had not anticipated, shows the ne- cessity of the precaution [| had used. The operation which they performed to unite platina and mercury was, in fact, nearly the reverse of that which they supposed they had repeated from me, and might have been applied perhaps with a better prospect of success towards the deconsposition of palladium. Messrs. Rose and Gehlen seem, in many parts of their paper, to question my having fused platina; and inform us, that although they had exposed this metal in the furnace of the royal porcelain manufactory of Berlin, in which Wedgewood’s pyrometer ceased to mark the degree of heat, they could not accomplish its fusion. Many of my friends in England have, however, seen the buttons which Job- tained, and which were not few in number. The flax which I had used was borax. But no mention is wade in any one of the operations of Messrs. Rose and Geblen of borax hav- ing been employed. fn many of their attempts they obtained an irregular and porous mass, which of course was of a specific gravity much inferior to that of platina; and it might be inferred from their paper that the diminution of specific gravity, which I had observed, was owing to the same cause. It is true, not only that I had very often obtained such a mass, but that I had frequently also observed no diminution whatso- ever in the specific gravity of the button which resulted from my operations. “But all those upon which I had founded the conclusions alluded to by Messrs. Rose and Gehlen were performed.in the following manner, and have been repéated since. A Hessian crucible was filled with lamp-black, and the contents pressed hard together. The lamp-black 30 On the Action of . lamp-black was then hollowed out to the shape of the eru- cible as far as one-third from the bottom, leaving that much filled with the compressed materials; this linmg, which adhered strongly to the sides of the crucible, was inade ex- tremely thin in order not to obstruct the passage of caloric. A cylindrical piece of wood, asa pencil, was then forced into the centre of the thick mass of lamp-black at the bottom, and the diameter of this rod was determined by the quantity of metal to be fused, or varied according to other circum- stances at pleasure. In general the axis of the cylindrical hole was about three or four times the diameter of the basis. After withdrawing the rod, the crucible was about half filled _ with borax. Upon this was placed the metal to be fused 5" and if it had been before melted into a cylindrical form, the axis of the metallic cylinder was placed horizontally, and was of course perpendicular to the axis of the cylindrical excavation at the bottom of the cover. More borax was — then added to cover the piece of metal, and another quan- tity of lamp-black was presssed hard over the whole in order ~ to keep it tight together. An earthen cover was finally luted to the crucible, and in this state it was exposed to heat in a forge, in which, upon another occasion, I had, in the presence of Messrs. Hatchett, Howard, Davy, and others, completely melted a Hessian crucible lined and prepared in the same manner. The fuel which I used was the patent coke of Messrs. Davey and Sawyer. In the present expe- riments T moderated the heat so as not materially to injure the crucible, and, upon taking it out of the fire, the lining was generally found so compact and so firm that it remained in a solid mass after the crucible was broken. When the metallic cylinder occupied the space at the bottom, it was natural to suppose that it had been fused; because in no other state but that of liquidity could it have run into the mould. In order, however, to prevent all objections, I had the precaution to make the hole of a different diameter from the metallic cylinder, and to observe whether the necessary change in the shape of the latter ensued. If, after such a test, repeated as often as required, I perceived that the metal did not vary in its specific gravity, 1 thought myself authe- rized to conclude that it was exempt from air. M. Richter says that he had hoped to have put himself in possession of a considerable piece of palladium by repeat- ing, with minute accuracy, the process which I had recom- mended as the best. He precipitated a mixed solution of platina and mercury by a solution of green sulphate of iron ; and, after varying the subsequent operations, to which he submitted Platina and Mercury upon each other. 3h submitted the product he had obtained by this method, he was led to the following important conclusions, amongst others of less consequence :—lIst, That two metals, the se- parate solutions of which are not acted upon by a third body, may be acted upon, and even reduced to the metallic state, by that same body when presented to them in one and the same solution. f 2dly, That mercury is capable of entering into combina- tion with platina, so that it cannot afterwards be separated by fire. From the first of these conclusions it 1s evident that metals in their metallic state are not incapable of che- mical action upon each other; and from the second, that mercury can be fixed (it is purposely that I use the alche- mical expression) by platina. In addition to the chemists above mentioned, I must name two more who in Germany have been occupied by palladium. -M. Tromsdorff, in a letter to the authors of the journal already quoted, mentions his having made some fruitless attempts to form this combination; and M. Klap- roth, in a letter to. M. Vauquelin, published in the dnales de Chimie tor Ventose, an 12, likewise says that he could not succeed in producing palladium. Messrs. Rose and Gehlen, as well as M. Richter, had conceived from my paper a reliance on the success of their experiments, which no words of mine had authorized, and have accus¢d me of enforcing the truth of my results with a degree of certainty which their observations do not coun- tenance. M. Richter supposed that the formation of pal- Jadium was attended with no difficulty; and in general they have laid so much stress upon this charge, that I should be inclined to think my paper had not been read by these chemists. In referring to it again, I find there is hardly a page in which I do not mention some failure; and no ex- periment, of the very few which occasionally succeeded, is related without my stating at the same time that it was re+ peatedly unsuccessful. As far as regards palladium, it is rather a narration of fruitless attempts than a description of an infallible process, and more likely to create aversion to the pursuit than to inspire a confidence of success. The course of experiments which I had made, as well before as after reading my paper to the society, took me up more than two months, and employed me from twelve to sixteen hours almost every day. I had frequently seven or eight operations in the forge to perform daily, and I do not ex- aggeratc the number of attempts I made during this time, as well in the dry as in the humid way, in stating them to have — 32 On the Aciion of have been one thousard. Amongst these, I had four suc- cessful operations. I persevered, ‘because, even in my fail- ures, I saw sufficient to convince me that [ should quit the road to truth if I desisted. After all my labour and fatigue I cannot say that I had come nearer to my object, of ob- taining more certainty in my processes. Their success was still a ‘hazard on the dice, against which there were many chances ; but till others had thrown as often as I had done, they had no solid right to deny the existence of such a com- bination. On this foundation none, I believe, have esta- blished such a right. Messrs. Rose and Gehlen do not say how often their experiments were repeated; but it 1s pro- bable that if they had been performed very often, these au- thors would not have neglected to mention it. M. Richter states his mercly as preparatory to more extensive researches 3 and M. Tromsdortf, as well as M. Klaproth, mention little more than the iow If the German chemists have con- cluded against my results, they have done so without*just or ounds, and without having bestowed upon them that labour aa assiduity for which” they are usually so remarka- ble. In this state of uncertainty the compound nature of palla- dium received an indirect, but a very able, support from some experiments of M. Ritter, the celebrated Galvanist of Jena, M. Ritter had ascertained the rank which a great number of substances hold in a Galvanic series, arranged according to the property they possess of becoming positive or neeative when in contact with each other. He had established the following order, the preceding substance being in a minus relation to that which comes next: Zinc, lead, tin, iron, bismuth, cobalt, antimony, platina, gold, mercury, silver, coal, galena, crystallized tin ore, kupfer nickel, sulphur pyrites, copper pyrites, arsenical py rites, evaphite, crystallized oxide of manganese. He had the goodness to try palladium in my presence, and found it to be removed, not only from what I believed to be its con- stituent parts, but altogether from among the metals, and to stand between arsenical pyniies and graphite. This re- sult led M. Ritter into a new and general train of reasoning, and induced him to undertake the examination of a great number of alloys, and of a variety of amalgams. He con- sidered the subject as a philosopher, and. his operations were those of a consummate experimentalist. It would be doing him an injustice to attempt an extract of bis ingenious paper, aac contains a series of the most initeresting ex- periments. ' I shall merely observe for the present. purpose, that Platina and Mercury upon each other. 33 that it very rarely happened that the mixture of two metals bore any determinate relation to the same metals when se- parate ; ‘that in every case the smallest variation in the pro- portions produced the most marked effects; and that M. Ritter has furnished us with an instrument calculated to detect the presence of such small quambities as have hi- therto been considered as out of the reach of chemistry. As palladium presents a very striking instance of the ano- maly, to which all compounds seem to be more or less sub- ject, by being removed altogether from the series of simple metals, this may serve to support the other proofs of its compound nature. One of the principal objections of those who dispute the truth of my conclusions with respect to palladium, is grounded upon the repeated failure of all the methods 1 had made use of in forming it; but this cannot be of very great w eight, when we Warader the uncertainty of many other operations of chemistry. The most simple are some- times liable to fail ; and the easiest analyses have often given different products in the hands of different chemists, , “who yet enjoy indisputable and equal rignts to the title of accu- racy. The progress which we have made in some parts of the science has not removed the obstacles which impede our advancement in others. We have no method of pro- ving the truth of an experiment except by repeating it; yet this often tends 1o show nothing more than contradictory results, and consequently the fallibility of the art. But a recent case has occurred which is_ perfectly analo- gous to that of palladium. oi a) % 36 Analytical. Experiments or rently beginning to decompose) of yellow. Its lustre is silky ; some of the specimens possess semi-transparency, but in general it is nearly opake. Its texture is loose, but small fragments possess great hardness, so as to scratch agate. It produces no effect on the smell when breathed upon ; has no taste; does not become electrical or phosphorescent by heat or friction; and does not adhere to the tongue till after it has been strongly ignited. Jt does not decrepitate before the flame of the blow-pipe; but it loses its hardness, and becomes quite opake. In consequence of the minute- ness of the portions in which it is found, few of them ex- eceding the size of a pea, it is very dificult to ascertain its specific gravity with any precision ; but from several trials I am disposed to believe that it does not exceed 2°70, that of water being considered as 1°00. IIL. Chemical Charaeters of the Fossil. The perfectly white and semi-transparent specimens of the fossil are soluble both in the mineral acids and im fixed _ alkaline lixivia by heat, without sensibly effervescing, and without Jeaving any notable residuum; but a small part re- mains undissolved when coloured or opake specimens are exposed to the alkaline lixivia. A small semi-transparent piece, acted on by the highest heat of an exeellent forge, had its crystalline texture de- stroyed, and was rendered opake ; but it did not enter into fusion. After the experiment it adhered strongly to the tongve, and was found to-have lost more than a fourth of its weight. Water and alcohol, whether hot or cold, had no effect on the fossil. When it was acted on by a heat of from 212° to 600° Fahrenheit in a glass tube it gave out am elastic vapour, which, when, condensed, appeared as a clear fluid possessing a slight empyrcumatic smell, but no taste different from that of pure water. The solution of the fossil in sulphuric acid, when eva~ porated sufficiently, deposited crystals which appeared in thin plates, and had all the properties of sulphate of alu- mine; and the solid matter, when redissolved and mixed with a little carbonate of potash, slowly deposited octaédral erystals of alum. The solid matter precipitated from the . solution of the white and semi-transparent fossil in muriatic acid, was in no manner acted upon by solution of carbo- nate of ammonia, and therefore it could not contain any glucine a mineral Production from Devonshire. 37 glucine or ittria; and its perfect solubility without residuum ia alkaline lixivia showed that it was alumine. Wien the opake varieties of the fossil were fully ex- posed to the agency of alkaline lixivia, the residuum never amounted to more than 1-20th part of the weight of the whole. In the white opake variety it was merely calca- reous earth; for, when dissolved in muriatic acid, not in excess, it gave a white precipitate when mixed with solu- tion of oxalate of ammonia, and did not affect solution of prussiate of potash and iron. In the green opake variety calcareous earth was indicated by solution of oxalate of ammonia: and it contained oxide of manganese; for it was not precipitated by solution of ammonia; but: was rendered turbid, and of a gray colour, by solution of prussiate of potash and iron. The residuum of the alkaline solution of the yellow va- riety, when dissolved in muriatic acid, produced a small quantity of white solid matter when mixed with the solu- tion of the oxalate of ammonia, and gave a light yellow precipitate by exposure to ammonia; but after this, when neutralized, it did not affect prussiate of potash and iron, so that its colouring matter, as there is every reason to be- lieve, was oxide of iron. IV. Analysis of the Fossil. Eighty grains of the fossil, consisting of the whitest and most transparent parts that could be obtained, were intro- duced into a small glass tube having a bulb of sufficient capacity to receive them with great ease. To the end of this tube a small glass globe, attached to another tube com- municating with a pneumatic mercurial apparatus, was joined by fusion by means of the blow-pipe. The bulb of the tube was exposed to the heat of an Ar- gand lamp, and the globe was preserved cool by being placed in a vessel of cold water. Jn consequence of this arrange- ment, the fluid disengaged by the heat became condensed, and no elastic matter could be lost. The process was con- tinued for half an hour, when the glass tube was quite red. A very minute portion only of permanently elastic fluid passed into the pneumatic apparatus, and when examined it proved to be common air. The quantity of clear fluid collected, when poured into another vessel, weighed 19 grains; but, when the interior of the apparatus had been carefully wiped and dried, the whole loss indicated was 21 grains. The 19 grains of fluid had a faint smell, similar to that of burning peat; it was transparent, and tasted like C3 distilled 382", . Analytical Experiments on distilled water; but it slightly reddened litmus paper. Tt produced no clenthents a in solutions of muriate of barytes, of aectite of lead, of nitrate of silver,.or of sulphate of iron. Vhe 59 grains of solid matter were dissolved m diluted sulphuric acid, which left no residuum; and the solution was mixed with potash in sufficient quantity to cause the alumine at first precipitated again to dissclve. What re- mained undissolved by potash, after bensg collected and properly washed, was heated strongly and weighed ; its quantity was 9 grain and quarter. It was white, caustic to the taste, and had all the properties of lime. The solution was mixed with nitric acid till it became sour. Solution of carbonate of ammonia was then poured into it till the effect of decomposition ceased. The whole thrown into a filtrating apparatus left solid matter, which, when carefully washed and dried at the heat of ignition, weighed 56 grains. -They were pure alumine: hence the general results of the experiments, when calculated upon, yndicated for 10@ parts of this specimen, Ofalumine. = - = - 70 Of lime eS - 2: 14 Ot fftid - - - 26°2 TUGSSia = - - Q°4 The loss I am inclined to attribute to some fluid remain= ing in the stone after the process of distillation ; for I have found, from several experiments, that a red heat’) is not suf- ficient to expel all the matter capable of being volatilized, and that the full effect can only be produced by a strong white heat. Fifty erains of a very transparent part of the fossil, by being exposed in a red heat for 15 minutes, lost 13 erains 3 but when they were heated to whiteness, the deficiency amounted to 15 grains 3 and the case w as similar in other trials, Different specimens of the fossil were examined with great care, for the purpose of ascertaining whether any minute portion of fixed alkali existed in them; but no indications of this substance could be observed: “the processes were conducted by means of solution of the unaltered fossil in nitric acid; the earths and oxides were precipitated =e the soliton by being boiled with carbonate of ammonia and after their separation the flutd was evaporated to dry - ness, and the nitrate of ammonig decomposed by heat, when no residuum occurred, A comparative analysis of 30 grains of a very pelucid specimen was made by ‘solution in lixiyium of potash. This ; specimen 1 a mineral Production from Devonshire. 39 specimen lost cight grains by long continued ignition, after which it easily dissolved in the lixivium by heat, Jeavine a residuum of a quarter of a grain only, w hich was red oxide of iron. The precipitate from the solution of potash, made by means of muriate of ammonia, weighed, when properly treated, 21 grains. Beers specimens were distilled in oes manner above de- scribed, and in all cases the water collected had similar pro- peitics. The only test by which the presence of acid matter ‘in it could be detected was litmus paper; and in some cases the effect upon this substance was barcly pere eptible. . General Observations. I have made several experiments with the hope of ascer- taining the nature of the acid matter in the water; but, from the impossibility of procuring any considerable quan- tity of the fossil, they have been w holly unsuccessful. It is, however, evident, ‘from the experiments already detailed, ren it is not one of the kuown mineral acids. . ram disposed to believe, from the minuteness of its pro- portion, and from the difference of this proportion in dit- ferent cases, that it is not essential to the composition of the stone; and that, as well as the oxide of manganese, that of iron, and the Liisi, it is only an accidental ingredient ; and on this idea the pure matter of the fossil must be considered as a chemical combination of abeut thirty parts of water and seventy of alumine. The expe eriments of M. Theodore de Saussure on the pre- cipitation * of alumine from its solutions, have demonstrated the affinity of this body for water; but as yet I believe ne aluminous stone, except that w nich I havé Just described, has been found, containing so large a proportion of water -as thirty parts in the hundred. The diaspore, which has been examined by M. Vauque- lin, and which loses sixteen or seventeen parts in the hun- dred by ignition, and which contams nearly eighty of ala- mine, and only three of oxide of iron, ts supposed by that excellent chemist to be a compound of alumine and water. Its physical and chemical characters differ, however, very ‘much from those of the new fossil, and other researches are wanting to ascertain whether the part of it volatilized by heat is ‘of the same kind. [ have examined ‘a fossil from near St. Austle, in Coyn- wall, very similar to the fossil from Barnstapic in ail its * Journal de Physique, tom, lit p. 280, C4 general 40 Ewperiments on }Vootx. general chemical characters ; and J have been informed that an analysis of it, made by the Rev. William Gregor some months since, proves that it consists of similar ingredients. Dr. Babington has proposed to call the fossil from Devon- shire Wavellile, from Dr. Wavel, the gentleman who dis- covered it; but if a name founded upon its chemical com- position be preferred, it may be denominated Aydrargiliite, from: déwe water, and agyiAags clay. aaevaQewawawawqoeauyq37—vnnamQ”qgeqoqaoaeeeeeeeeeee—ee—eeeeeeeeeee eee VI. Experiments on Wootz. By Mr. Davip Musnet*. As Tur following experiments were made at the request of sir Joseph Banks, on five cakes of wootz, with which he supplied me for that purpose. As the cakes, which were numbered 1, 2, 3,4, 5, were not all of the same quality, it will be proper first to describe the differences observable in their external form and appearance. No. 1. was a dense solid cake, without any flaw or fungous appearance upon the flat, or, what I suppose to be, the upper side. The round or under surface was covered with small pits or hollows, two of which were of considerable depth ; one through which the slit or cut had run, and another nearly as Jarge towards the edge of the cake. These de- pressions, the effects, as 1 suppose, of a species of crystal- lization in cooling, were continued round the edges, and even approached a little way upon the upper surface of the wootz.- The cake was a quarter of an inch thicker at one extre- mity of the diameter than that at the other; from which T infer, that the pot or crucible in which this cake had been made had not occupied the furnace in a vertical position. Its convexity, compared to that of the other five, was se- cond. Upon breaking the thin fin of steel, which connects the half cakes together, I found it to possess a very small dense white grain. This appearance never takes place but with steel of the best quality, and is less frequent in very high steel, though the quality be otherwise good, Upon examining the break with attention, I perceived several lamine aud minute cells filled with rust, which in working are never expécted to unite or shut together. The grain otherwise was uniformly regular in point of colour and size, and possessed a favourable appearance of steel. * From the Transactions of the Reyal Society for 1805. No. 2. Experiments on ]¥ootx. AY No. 2. This cake had two very different aspects; one side was dense and regular, the other hollow, spongy, and protuberant. The uncer surface was more unitormly honey- combed than No. 1; the convexity in the middle was greater, but towards the edges, particularly on one side, it became flatter. The grain exposed by breaking was larger, bluer in colour, and more sparkling than No. 1. In breaking, the fracture tore but slightly out, and displayed the same un- connected Jaminz, witb rusty surfaces, as were observed in No. 1. Beside these, two thin fins of malleable iron pro- jected from the unsound side, and seemed incorporated with the mass of steel throughout. Towards the centre of the break, and near to the excrescence common to all the cakes, gronps of malleable grains were distinctly visible. The same appearance, though in a slighter degree, mani- fested itself in various places throughout the break. No. 3. The upper suriace of this cake contained several deep pits, which seemed to result from the want of proper fluidity in fusion. They differed materially from those de- scribed upon the convex sides of No. 1 and 2, and were of that kind that would materially affect the stcel in forging. The under or convex side of this cake presented a tew crystalline depressions, and those very small; the convexity was greater than that of No. 1 and 2, the fracture of the fin almost smooth, and only in one place exhibited a small degree of tenacity in the act of parting. In the middle of the break, about half an inch of soft steel was evident; and in different spots throughout numerous groups of malleable grains and thin lamine of soft blue tough iron made their appearance. No. 4. was a thick dense cake possessed of the greatest convexity; the depressions upon the under side were neither so large nor so numerous as those in No. 1 and 2, nor did they approach the upper surface of the cake further than the acute edge. This surface had the most evident marks of hammering to depress the feeder, or fungous part of the metal, which in the manufacturing seems the gate or orifice by which the metal descends in the act of gravitation: The break of this cake, however favourable as to external appearance, was far from being solid. Towards the feeder it seemed loose and crumbly, and much oxidated.. The grain divided itself into two distinct strata, one of a dense whitish colour, the other large and blucish, containing a number of small specks of great brilliancy. Several irre- gular lines of malleable iron pervaded the mass in various 8 places, 42 Experiments on l¥Vootx. places, which indicated a compound too heterogeneous for good steel. 5th cake. This was materially different in appearance from any of the former. It had received but little ham- mering, yet was smooth, and free from depressions, or honey comb on both surfaces. The feeder, instead of being an excrescence, presented a deep concave beautifully cry- stallized. In breaking, the fracture tore out considerably, but pre- sented a very ‘irregalar quality of grain. That towards the under surface was smal! and uniform, but towards the flat or wpper surface it increased in size, and in the blueness of its colour, till it passed into the state of malleable iron. The break of this steel, though apparently soft, was the least homogeneous of the whole, and throughout it presented a very brilliant arrangement of crystal, w hich in other steel is always viewed with suspicion. General Remark. ’ Uniformly the grain and density of the wootz are homo- geneous, and free from malleable iron towards the under er round surface; but always the reverse towards the feeder or upper side. Remarks in Forging. Wo. 1. One-half of the cake was heated slowly, Dy an annealing heat, to a deep red, and put under a sharp broad- mouthed ohisél with a small degree of taper. It eut with difficulty, was reheated, and cracked a little towards one end of the shit or cut or iwinally j in the cake. he heat in this trial was so moderate that I was afraid that the crack had arisen from 2 want of tenacity, occasioned by the heat being too low. ‘The other balf was heated a few shades higher, and sub- jected to the same mode of cutting : before the chisel had half way reached the bottom, the piece parted in two in the direction of tht depression made by the cutting instrument. The. additional heat in this, instance proved an injury, while the cracking of the steel in both cases , particularly the former, was a certain proof of the: abundanee, or rather of the excess of the steely principle. The fractures of both half cakes, now obtained for a se- cond time, were materially different from that obtained by the simple division of the cake. The grain was nearly uni- form, distinctly marked, but of too wray a colour for ser- wiecabic steel. Two of the quarters being drawn into nea ’ ~ : bar S Experiments on JVootz. 43 bars under hand-hammers at a low heat, one of them con- taincd a number of cracks and fissures. The fracture was gray, tore out a litUe in breaking, but was otherwise yolky and excessively dense, A small bar, of penknife size, was improved greatly i in drawing down, and had wi one crack iu thirteen inches of length. The grain and fracture were both highly improved: by “this additional labour; the tena- city of the steel was greater, arid it stood firmly under the hammer at a bright red heat. The other two. quarters of this cake were squared a little, and successively put uader a tilt hammer, of two hundred weight, going at the rate of three hundred blows per mi- nute, and drawn into small penknife size. One of the bars from an outside piecc, always the most solid, was entirely free from cracks, and lad only one small scale running upon one side. These bars exhibited a iduptier break than those drawn by hand; the colour was whiter, and the grain possessed 2 more regular and silky appearance. Forging No. 2. One-half of this cake was heated to a searlet shade, and ‘put under the cutting chisel; it was at first struck lightly, then reheated, and cut compar ratively soft; but a small “crack had over-run the progress of the aitieah, Its softness im cutting was attributed to an evident want of solidity. The other half cake felt harder under the hammer, but proved afterwards spongy throughout the mass. In the act of ,cut- ting, a loose pulverized matter was disengaged from some of the cells, possessed of a shining appearance. The fractures obtained in consequence of the division of the half cakes presented a flattish crystallized appearance, more resembling very white cast iron than stecl capable of being extended under the hammer. One of the middle cuts was cutircly cellular with crystallized: interiors, and inca- pable of drawing 5 the corresponding cut of the other half cake was drawn into a straight bar three quarters of an inch in breadth and three- -cighths thick, but was covered with eracks and flaws from end to end. The colour of the break was one shade hehter than No. 13; it tore less out, was equally yolky, and possessed on ihe whole an aspect very unfavourable for good steel. The other two outside quarters were also drawn into shape, one under the tilt hammer, and the other by hand. These were more solid in the fracture, possessed fewer surface- cracks, stood a higher degree of heat, tore out more, and exhibited 44 Experiments on Hotz. exhibited a silky glossy grain, at least two shades helter in the colour than the centre pieces. Forging 3d Cake. One-half of this cake, first subjected to be cut, was found softer than any of the preecding, and exhibited no symptom of cracking. The other half was cut at three heats, but found loose and hollow if the extreme. .A considerable portion of the same bnilliant powder, formerly noticed, was here again disengaged. It was carefully taken up for exa- mination, and found to be very fine ore of iron in a pulve- rescent state, very obedient to the magnet, and without any doubt an unmetallized portion of that from which wootz 1s made. This curious circumstance led me to examine every pore and cell throughout the whole fragments. On the upper surface of two of them I found small pits containing a por- tion of the ore, which had been shehtly aggiutinated im the fire, but still highly magnetic. The upper surtace of the resent cake, close by the gate or feeder, contained a large pit filled with a stratum of semi-fused ore, surmounted by a mass of vitrified matter, which bore evident marks of con- taining calcareous earth. “Those who have devoted sufficient. attention to the affi- nities of iron and earths for carbon, will be surprised to find that, on this particular subject, the rude fabricators of steel im Hindostan have got the start of our more polished coun- trymen in the manufacture.of steel. Two bars of wootz were formed from this cake, and these, in point of quality, inferior to any of those formerly produced. The appearance of the. metal was more varied, Jess homogeneous, and contained more distinct laminz with rusty surfaces than either of the two former cakes. It appeared highly probable, from the observations that occurred in forging, and in the examination of the cake, that the original proportion of mixture was such as would have formed a quality ot steel softer than No. 1 and 2; but as steel of such softness requires a greater heat to fuse it than when more fully saturated with carbonaceous matter, it is probable that the furnace had not been sufficiently powerful to occasion complete fusion of the whole mass, and generate a steel homogeneous in all its parts. Forging 4th Cake. Both halves of this cake cut pleasantly, and with a degree of tenacity and resistance, mixed at the same time with soft- ness Experiments on T¥oote. 45 ness beyond what was experienced in any of the former cakes. Two quarters of this cake were drawn under the ult hammer, and one by hand. The resulting bars wert nearly perfect. A slight scale was observable upon the bar from that quarter w bich contained the figure. The fracture was solid, though not homogeneous as to quality and ca- lour, ad it appeared pretty evident that.a considerable por- tion of one side through the whole bar was in the state of malleable iron, and of course not capable uf being hardened. It wasa subject of considerable regret that the cake the most perfect and the most tenacious of the whole, in the process of forging, should get an imperfection which rendered it useless for the perfect purposes of steel. ; Forging 5th Cake. . The first half of this cake cat uncommonly soft for wootz, a by cracking before the chisel still exhibited a want of proper tenacity. The next half cut equally soft, but with more tenacity. Two quarters of this cake drew readily out under the tilt hammer, and a third was drawn by hand at a bright red, sometimes approaching ‘to a faint white heat. None of the bars thus obtained were uniformly free from cracks and scale, although the fracture exhibited a fair break of a light blue pie and the grain was distinctly marked, and free from yolks. General Remarks. The formation of wootz appears to me to be in conse-" quence of the fusion of a pecahar ore, perhaps calcareous, or rendered highly so by mixture of calcarcous earth along with a a portion ‘of carbonaceous matter. That this is per- formed in a clay or other vessel or crucible, is equally pre- sumable, in which the separated meial is allowed to cool; hence the crystallization that occupies the pits and cells found in and upon the under or rounded surface of the wootz cakes. : The want of homogencity and of real solidity in sineads every cake of wootz, appears to ine to be a direct conse- quence of the want of heat sufiiciently powerful to eflect a perfect reduction ; what strengthens this supposition much Is, that those cakes that are the hardest, 7. e. that contain the greatest quantity, of caihonaceous matter, and of course form the most fusible steel, are always the most solid and homogeneous. On the contrary, those cakes into which the cutting chisel most easily fide its way, are in general : cellular, 46 Raperiments on [Vootz. cellular, replete with lamin, and abound 1 in veins of mal= leable iron. It is probable, had the native of Hindostan the means of rendering his cast steel as fluid 4 water, it would have oc- curred to him to have run it into moulds, and by this means have acquired an article uniform in its quality and conye- nient for those purposes to which it is applied. The hammering, which is evident around the feeder and upon the upper surface in general, may thus be accounted for :—When the cake is taken from the pot or crucible, the feeder will most probably be slizhtly elevated, and the top of the cake partially covered with small masses of ore and steel iron, which the paucity of the heat had left cither im- perfectly separated or unfused. These most probably, to make the product more marketable, are cut off at a second heating, and the whole surface hammered smooth. I have observed the same facts and similar appearances in operations of a like nature, and can account satisfactorily for it as follows : The first portions of metal that are separated in experi+ ments of this nature; contain the largest share of the whole carbon introduced into the mixture. It follows, of course, ‘that an inferior degree of heat will maintain this portion of metal in a state of fluidity, but that a much higher tempe- rature is requisite to reduce the particles of metal, ‘thus for a season robbed of their carbon, and bring them into con- tact with the portion first rendered fluid, to receive their proportion of the steely principle. Where the heat is lan- ruid, the descent of the last portions of iron is sluggish, the mass below begins to lose its fluidity, while its disposi- tion for giving out “carbon is reduced by the eradnal addition of more iron. An accumulation takes place of metallic masses of various diameters, rising up for half an inch or more into the elass that covers the metal; these are neatly welded and inserted into each other, and diminish in dia-~ meter as they go up. The length or even the existence of this feeder or excrescence depends upon the heat in gene- ral, and upon its temperature at different periods of the same process. “If there has been sufficient heat, the surface will be convex, and uniformly crystalline; but if the heat has been urged, atter the feeder has eae formed and an affinity established between it and the gteclified mass below, it will only partially disappear in the latter, and the head or part of the upper end of the feeder will be found suspended in the glass that covers the steel. he Experiments on IY ootz. 47 The same or similar phenomena take place in separating erude iron frem its ores, when highly carbonated, and diffi - cult, from an excess of carbon, of being fused, The division of the wootz cake by the manufacturers of Uindostan, I apprehend, is merely to, facilitate its subse- quent application to the purposes of the artist ; it may serve at the same time as a test of the quality of the steel. To ascertain, by direct experiment, whether wootz ow ed its hardness to an extra quantity of carbon, the following experiments were performed with various portions of woot, of common cast steel and of white crude iron, ‘airmen that, in operations with iron and its ores, I have always found the comparative measure of carbon best ascertained by the quantity of lead which was reduced from flint glass. 1st Cake. Fragments of wootz - - 65 grs. Pounded flint class three times the weight 195 This mixture was exposed to a heat of 160° of Wedge- wood, and the wootz fused. into a well crystallized spherule of ON A thin crust of revived lead was found below the wootz, which weighed 9 grains, or $22, the weight of the avoctz. ed Cake. : Fragments of wootz - - - $0 grs. Flint glass, same proportion as above - 240 The fusion of the mixture in this experiment was pro- ductive of a mass of lead weighing 10 grains, equal to 1-Sth the weight of the wootz. 3d Cake. Fraements of wootz - - 75 ors. Flint glass - - -~ § 995 ~The mass of lead precipitated beneath the steel in this experiment, amounted to 9 grains, or 72; the weight of the wootz employed. 4th Cake. , Fragments of wootz = - == ~— 93. ars. Flint glass = = mificn 279 Lead obtained, precipitated from the glass by means of the carbon of the wootz, 14+ grains; equal to 56, the weight of the wootz. 5th Cake. Fragments of wootz - a 69 gts, Flint glass ° - . ay) 209 The 48 Experiments on Wootz. The lead revived in this experiment amounted to 7 grains, which is equal to 3°22, the weight of the wootz. “Gth. Cast Steel formed with 1-60th Part its weight of Carbon. Fragments - > 90 grs. Crystal glass - - 270 Lead revived 8} grains, equal to ;24, the weight of the steel introduced. 7th. White cast Iron dropt while Fluid into Water. Fragments - - 103 grs. Crystal glass - - 309 The fusion of this precipitated 23+. grains of lead, which is equal to 22,8, the weight of the cast iron. Recapitulation of these Experiments. Ist Cake of wootz revived of lead - 139 grs. ed ditto - - - "125 3d = —s ditto - - - "120 4th ditto - - - +150 5th ditto - - - “102 Steel containing 1-60th of its weight of carbon -094 Cast iron - - - - "293 It would appear to result from these experiments, that wootz contains a greater proportion of carbonaceous matter than the common qualities of cast steel in this country, and that some particular cakes approach considerably to the na- ture of cast iron. This circumstance, added to the in:per- fect fusion which generally occurs in the formation of wootz, appears to me to be quite sufficient to account for its refractory nature, and unhomogencous texture. Notwithstanding the many imperfections with which wootz is loaded, it certainly possesses the radical principles of good steel, and impresses us with a high opinion of the ore from which it is formed, The possession of this ore for the fabrication of steel and’ bar iron, might to this country be an object of the highest importance. At present it is a subject of regret that such a source of wealth cannot be annexed to its capital and ta- lent. Were such an event practicable, then our East India company might, in their own dominions, supply their stores with a valuable article, and at a much inferior price to any they send from this country. VII. An f 49 j VU. An Essay on Medical Entomology. By ¥. Cuau- METON, Physician to the Army. [Concluded from p. 351-] F ormica—The Ant.—These insects, on the pedicle of their abdomen, have a small vertical scale, a large head, small eyes, broken antenne, and strong thandibles. Each species consists of three kinds ; males and females, provided with long wings, and neutrals or labourers, who are desti- tute of them. The two last kinds have sharp retractile stings. Ants live like bees in large societies. The government of both is founded on injustice, ingratitude, and barbarity. There is no difference but in the choice of the victims ; in a bee-hive the niales are banished or cut in pieces after they have given birth to a numerous family; in an ant-hill the females are cruelly expelled as soon as their eggs have been deposited *. aig The strong penetrating emanations which escape from an, ant-hill, have given reason to suspect that the insects which inhabit it possess medicinal properties; and this conjecture has often been verified by experience. A cataplasm of bruised ants, with their nymphz, commonly. called eggs, and a portion of their habitation, has been sometimes ap- plied with success to limbs attacked with rheumatic pains, cedema, or palsy. The samic epithem has increased the energy of the organs of generation.. Baths rendered stimu- lating by the expressed juice of a large quantity of ants, have been found very efficacious in similar cases. The desire, no doubt, of having at all seasons a medicine proved to be so useful, gave rise to the invention of oil of ants. In re- gard to Hoffman and Kunrath’s water of magnanimity, its pompous title was never justified by experience. It may be readily conceived, that in such compositions the virtue of the ants is altered or destroyed, when it is considered that it resides essentially in the acid, of which these insects fur- nish, by mere lixiviation or distillation, a quantity equal to half their weight. The formic acid, diluted with water, is agreeable to the piste, and with the addition of a little sugar forms excel- ent lemonade. Ardrisson aud Cihrne have propased to substitute this acid in the room of vinegar for domestic * Lam of opinion, however, that these animals die a natural death, like the dones. Vol. 22, No, 85, June 1805, D purposes. 50 On Medical Entomology. purposes. Alcohol, with which it perfectly mixes, ought, as we may say, to give it wings; to multiply its virtues, and in particular, to increase that of rousing the palled organs. The formic acid unites so easily with alkalis, that, if a piece of linen imbibed with these bases be presented to an ant-hill, you will obtain formiates of soda, potash, of ammonia. I have strong reasons for believing that these two salts are preferable to the acetites of potash and am- monia ; and if the formic acid has a great analogy to the phosphoric, as Thouvenel thinks, the formiate of soda would furnish the healing art with a gentle purgative, much cheaper than the phosphate. ORDER VII. APTFERA. Scoreto—The Scorpion.—The scorpion is distinguished by characters so striking that it is impossible not to know iton the first view. It has a long articulated tail, termi- nating in a sharp moveable hook, which to this animal is both a defensive and offensive weapon. Under its man- dibles there are enormous feelers, terminating in pincers, like those of crabs. These feelers, which Spielman calls cheliform antennz, are much longer than the fect. The latter are eight in number, as well as the eyes. At the posterior part of the breast also there are two dentated scales in the form of combs, ‘the use of which has not yet been discovered *. , Scorpio Euvropxus.—The European scorpion lives like the other species in the warm or very temperate climates. It is commen in Spain, in Italy, and in the south of France. Its length varies from. one to two inches : its pincers are oval and angular: its combs have sixteen or eighteen teeth. If the sting of the European scorpion were mortal, as has been asserted, it would be a powerful cause of depopulation in certain towns, in which I have seen this insect mhabit- ing without molestation the greater part of the houses, and -infestitig even the beds. We must not, therefore, give implicit belief to the tales circulated on this subject. I was stung at Lodi by a brown scorpion an inch in length, and of the size of a goose quill. The result was only a slight pain, and a superficial phlogosis, which was soon dissi- * It is supposed that they serve as organs of respiration, and that they ave an analogy to the branchiz of the crustacea, for scorpions in their form approach'to'that order of animals. pated, On Medical Entomology. 5i pated*. Several soldiers were also stung in their lodgings, and at the military hospital, which swarmed with these animals, Some of the patients came to me with the in- sects still adhering to the part of the body which they had wounded: none of them experienced any accideni more gerious than I did. G. Fabbroni of Florence, G. Vasi of Rome, and G. L. Targioni of Naples, assured me that the sting of the scorpion is scarcely ever accompanied with alarming symptoms in these cities, though the temperature there is much warmer thanin Lombardy. These imaginary dangers, however, have given rise to the preparation of oil of scorpions, which, notwithstanding the present improved state of science, is classed in several new works among the alexipharmacs : we must not, however, reject with con- tempt the testimony of Monardes, who pretends that he found benefit in the plague from liniments of this. oil, as the horrid effects of that terrible scourge have often been prevented by frictions with olive oil f. The Arabs injected oil of scorpions into the bladder to dissolve the stone, and it is needless to add that their at- tempts were always fruitless. The moderns have severely reproached the Arabians for their stupid confidence ; but they have not been less credulous or move successful: we have seen them extol saponaccous and alkaline preparations, lime water, the interior bark of the lime tree, and, in par- ticular, the trailing arbutus, arlutus wa urst. This shrub has in turns heated the imagination of Barbeyrac, Quer, Girardi, Murray, de Haen, &c. The last does not hesitate to propose it as areal lithontriptic. But no one is igno- rant that this man, so haughty and so passionately fond of fame, has not always impressed his writings with the seal of truth. If there exists a solvent of the stone in the bladder, it must be discovered by chemistry, and the phi- Janthropic labours of Fourcroy seem already to hold out a consoling prospect. But still our hopes are very feeble, and it is much to be apprehended that the resources of me= dicine will be always confined to one infallible lithontriptic; namely cystotomy. Cancer—The Cral.—The numerous species which con- stitute this genus have forms exceedingly various, Their * I caused myself to be stunt at Florence, and with the same result, in the presence of F. Fontana, who had, been employed in analysing chemically the European Scorpion, and who had found in the juices of that insect an acid completely formed, and a gummy viscid matter, avalegous to the poison of the viper. leaite ( f Desgenette’s Hist. Mcd. de l’Armée d’Orient. De internal 52 On Medical Eniomology. internal and external ‘organization seems to remove them from al} other insects except the monoculi, to which they have a great affinity, On this account several naturalists have united these two genera under the name of erustacea. But was it necessary to make of themr a separate class, and will naturalists never become sensible of the inconvenience of those endless divisions which render zoology an imexpli- cable chaos ? Crabs have a head and breast confounded. in one piece, which bears five pair of legs, the first of which terminate generally in pincers. The tail is of greater or lesa size, and: formed of different articulations : their eyes are compound- ed, and supported by a moveable pedicle : they have for the. most part four antenna formed of threads, sometimes, double or treble: the branchiz are very complex: they: have a muscular heart, from: which proceed a great many vessels; a stomach supported by an osseous structure, and containing three hard stony pieces, which pound their aliments. The organs of generation are double im each. sex, and have their exit at the bottom of one of the pairs of legs. All crabs are aquatic, and change their shell every year = at the same time also they throw up the stones from theiz stomach *. The cray-fish (Cancer astacus) is commonly served up at our tables. The great horse crab (Cancer pagurus), the lobster (Can- cer gammarus), the prawn (Cancer serratus), the white shrimp (Cancer squilla), and the spiny lobster (Cancer komarus), have a more delicate taste. They all furnish an abundant quantity of gelatine, which renders broth nutritive and detergent. It is by the first of these properties that it acts in phthisis: it develops the seeond in cutaneous dis- eases, and Pinel recommends it in leprosy+. 1 am of opi- nion with Bichat, that, notwithstanding the sarcasms sometimes just thrown out against the humoral medicine, it rests om areal foundation ; and that in a multitude of cases every thing ought to be referred to a vitiated state of the humours f. At the period when the cray-fish casts its. shell, to assume a new one, there are found on the sides of its stemach, between the membranes of that viscus, two cal- careous concretions, which are employed as absorbents, * Cuvier Tab. Element. de l'Hist. Nat. des Anim. p. 456. + Nosogr. Philos. deux. edit. n. 858. $ Anat. Gener. part I. p, 256% under On Medical Entomology. 53 under the ridiculous denomination of crab’s eyes. A simi- jar virtue is ascribed to the pincers of the larger species, Cancer pagurus, gammarus, &c. ‘These inert and hurtful substances have, however, been long since proscribed by sound chemistry. Were it proved that a morbific affection was produced by the presence of an acid in the primary or secondary passages, pure and not carbonated magnesia would be the most proper remedy. Ontscus—The Wood-louse—The body of this insect is ‘oval, and formed of articulated segments, the first seven of which have each a pair of legs; their eyes are compounded and fixed, and their antennz setaceous. The common wood-louse, Oniscus asellus, the tail of which is terminated by two filiform appendages, or the armadillo, which is indebted for its denomination to the property it has of folding itself double on the least danger, is the one chosen for medicinal purposes. The trials made by Lister, Neumann, and Cartheuser, to determine the constituent principles of wood-lice, were ouly rude sketches. Thouvenel threw some light on the chemical analyses of these insects, and on the use ‘of them in the art of healing. When distilled alone in a balneum marie, they gave a water sufficiently alkaline to render syrup of violets greenish. Being then treated with water and alcohol, they furnished a fourth part of their weight of extractive and cirous matter, which ether separated from each other, dissolving the latter without touching the former. The expressed juice »f wood-lice contains muri- ates of lime and of potash, in which reside the dissolving and aperient qualities, which cannot be refused to these inseets. Dioscorides and Entmuller extol the efficacy of them im obstructions of the abdominal viscera. Riviere has confirmed the utility of them in arthritic affections, foul ulcers, and tumors of the breasts of women. They are killed by the steam of alcoho], and are then dried and pul- verised. This preparation is superfluous, and even preju- dicial, when these msects are employed in disorders of the ‘breast. 1 have observed the good effects of the juice of these insects in two chronic pulmonary catarrhs. The “preparation I prescribed in spoonfuls was as follows : Ix. Infusion of creeping ivy five ounces. Expressed juice of 150 wood-lice, bruised alive. Refined sugar, pulverised, one ounce. Syrup of poppies one ounce. Ethereous sulphuric alcohol twelye drops. D3 VIII. Short VIII. Short Account of Travels between the Tropies, by Messrs. Humsoipt and BONPLAND, im 1799, 1800, 1801, 1802, 1803, and 1804. By J. C. DELAME- THERIE. {Concluded from p. 362.] f Donune his residence at Quito M. Humboldt received a letter from the French National Institute, informing him that captain Baudin had set out for New Holland, pursuing an easterly course by the Cape of Good Hope. He found it necessary therefore to give up all idea of joining him, though our travellers had entertained this hope for thirteen months, by which means they lost the advantage of an easy passage from the Havannah to Mexico and the Philippines. It had made them travel by sea and by land more than a thousand Jeagues to the south, exposed to every extreme of temperature, from summits covered with perpetual snow to the bottom of those profound ravines where the thermo- meter stands night and day between 25° and 31° of Reau- mur. But, accustomed to disappointments of every kind, they readily consoled themselves ‘on account of their fate. ‘Lhey were once more sensible that man must depend only on what can be produced by his own energy ; and Baudin’s voyage, or rather the false intelligence of tlie direction he had taken, made them traverse immense countries towards which no naturalist perhaps would otherwise have turned his researches. M. Humboldt being then resolved to pursue his own expedition, proceeded from Quito towards the river Amazon and Lima, with a view of making the important observation of the transit of Mercury over the sun’s disk. Our travellers first visited the ruims of Lactacunga, Hambato, and Riobamba, a district convulsed by the dreadful earthquake of the year 1797. ‘They passed through the snows of Assonay to Cuenca, and thence with great difficulty, on account of the carriage of their struments and packages of plants, by the paramo of Saraguro to Loxa. It was here, in the forests of Gonzanama and Ma- Jacates, that they studied the valuable tree which first made known to man the febrifuge qualities of cinchona. ~The extent of the territory which their travels embraced, gave them an advantage never before enjoyed by any botanist, namely, that of comparing the different kinds of cinchona of Santa Fé, Popayan, Cuenca, Loxa, and Jaen, with the euspa and cuspere of Cumana and Rio Carony, the latter of which, named improperly Cortex angusiur@, appears to- an r= { belong a Account of Travels letween the Tropics. 55 helong te a new genus of the pentandria monogynia, with alternate leaves. ve Irom Loxa they entered Peru by Ayavaca and Gounca- bamba, traversing the high summit of the Andes, to pro- ceed to the river Amazon. They had to pass thirty-five times jn the course of two days the river Chamaya, some- times on a raft, and sometimes by fording. They saw the superb remains of the causeway of Ynga, which may be compared to the most beautiful causeways in France and Spain, and which proceeds on the porphyritic ridge of the Andes, from Cusco to Assonay, and is furnished with éamlo (inns) and public fountains. They then embarked on a ratt of ovhroma, at the small Indian village of Cha- niaya, and descended by the river of the same name, to that of the Amazons, determining by the culmination of several stars, and by the difference of time, the astronomical posi- ion of that confluence. La Condamine, when he returned from Quito to Para and to France, embarked on the river Amazon only below Quebrada de Chucunga; he therefore observed the longi- tude only at the mouth of the Rio Napo. M. Humboldt endeavoured to supply this deficiency in the beautiful chart of the French astronomer, navigating the river Amazon as far as the cataracts of Rentema, and forming at Tomependa, the capital of the province of Jaen de Bracamorros, a de- tailed plan of that unknown part of the Upper Maranon, both from his own observations and the information ob- tained from Indian travellers... M. Bonpland in the mean time made an interesting excursion to the forests around the town of Jaen, where he discovered new species of cin- chona ; and after greatly suffering from the scorching heat of these solitary districts, and admiring a vegetation rich in new species of Jacquinia, Godoya, Porteria, Bougainvillea, Colletia, and Pisonia, our three travellers crossed for the fifth time the cordillera of the Andes by Montan, in order to return to Peru. , They fixed the point where Borda’s compass indicated the zero of the magnetic inclination, though at 7 degrees of “south Jatitude. They examined the mines of ualguayoc, where native silver is found in Jarge masses at the height of 2000 toises above the level of the sea, in mines, some metalliferous veins of which contain. petrified shells, and which, with those of Huantajayo, are at present the richest of Peru. From Caxamarea, celebrated by its thermal waters, and by the ruins of the palace of Atahualpa, they descended to Truxillo, in the neighbourhood of which are D4 found 56 Account of Travels between the Tropics. found vestiges of the immense Peruvian city of Mansiche, ornamented with pyramids, in ane of which was discovered, jn the eighteenth century, hammered gold to the value of more than 150,000], sterling. On this western declivity of the Andes our travellefs en- joyed, for the first time, the striking view of the Pacifie Ocean ; and trom that long and narrow valley, the inhabi- tants of which are unacquainted with rain or thunder, and where, under a happy pity the most absolute pewer, and that most dangerous to man, theocracy itself, seems to imitate the beneficence of nature. - From Truxillo they followed the dry coasts of the South Sea, formerly watered and rendered fertile by the canals of the Ynga; nothing-of which remains but melancholy ruins. When they arrived, by Santa and Guarmey, at Lima, they remained some months in that interesting capital of _ Peru, the inhabitants of which are distinguished by the vivacity of their genins and the liberality of their sentiments, M. Humboldt had the happiness of observing, in a pretty complete manner, at the port of Callao at Lima, the end of the transit of Mercury: a circumstance the more fortu- nate, as the thick fog which prevails at that season often prevents the sun’s disk from being seen for twenty days, He was astonished to find in Peru, at so immense a distance from Europe, the newest literary productions in chemistry, mathematics, and physiology; and he admired the great intellectual activity of a people whom the Europeans accuse of indolence and |yxury, In the month of January 1803 our travellers embarked in the king’s corvette La Castora for Guyaquil; a passage which is performed, by the help of the winds and the currents, in three or four days, whereas the return from Guyaquil re- quires as many months. In the former port, situated on the banks of an immense river, the vegetation of which in palms, plumeria, talerneemantana, and scitaminee, is ma- jestic beyond all description. They heard growling every moment the volcano of Catopaxi, which made a dreadful explosion on the 6th of January 1803, They immediately set ont that they might have a nearer view of its ravages, and to visit it a second time; but the unexpected news of the sudden departure of the Atlanta frigate, and the fear of not finding another opportunity for " geveral months, obliged them to return, after being tor- pena for seven days by the mosquitoes of Babaoyo and ‘ibar, They had a favourable navigation of thirty days ‘a ; t { Pacific Account of Travels between the Tropics. 57 Pacific Ocean to Acapulco, the western port of the king- dom of New Spain, celebrated by the beauty of its bason, which appears to have been cut out in the granite rocks by the violence of earthquakes ; celebrated also by the wretch- edness of its inhabitants, who see there millions of plastres embarked for the Philippines and China; and unfortunately celebrated by a climate as scorching as mortal. M. Humboldt intended at first to stay only a few months in Mexico, and to hasten his return to Europe ; his travels had already been too long; the instruments, and particularly the time-keepers, began to be gradually deranged; and ail " the efforts he had made to get new ones had proved fruit- less, Besides, the progress of the sciences in Europe is so rapid, that in travels of more than four years a traveller may see certain phenomena under points of view which are si a interesting when his labours are presented to the ublic, 5 M. Humboldt flattered himself with the hope of being in England-in the months of August or September 1803; but the attraction of a country so beautiful and so variegated as the kingdom of New Spain, the great hospitality of its inhabitants, and the dread of the yellow fever at Vera Cruz, which cuts off almost all those who between the months of June and October come down from the mountains, in- duced him to defer his departure till the middle of winter. After having occupied his attention with plants, the state ‘of the air, the hourly variations of the barometer, the phe- nomena of the magnet, and in particular the longitude of Acapulco, a port in which two able astronomers, Messrs. Espinosa and Galeano, had before made observations, our travellers set out for Mexico. They ascended gradually from the scorching valleys of Mescala and Papagayo, where the thermometer in the shade stood at 32° of Reaumur, and where they passed the river on the fruit of the crescenlia " pinnata, bound together by ropes of agave, to the high plateaux of Chilpantzingo, Tehuilotepec and Tasco. At these heights of six or seven hundred toises above the level of the sea, in consequence of the mildness and cool- ness of the climate, the oak, cypress, fir, and fern, begin ‘to be seen, together with the kinds of grain cultivated in Europe. Having spent some time in the mines of Tasco, the oldest and formerly the richest in the kingdom, and having studied the nature of those silvery yeins which pass from the hard calcareous rock to micaceous schist and inclose foliaceous gypsum, they ascended, by Cuernaraca and the cold wi ) ° 58 Account of Travels between the Tropics, of Guchilaqua, to the capital of Mexico. This city, which has 150,000 inhabitants, and stands on the site of the old Yenochtitlan, between the lakes of Tezcuco and Xovhimilo, which have decreased in size since the Spaniards, to lessen the danger of inundations, have opened the mountains of Sincoc, is imtersected by broad straight streets. It stands in sight of two snowy mountains, one of which is named Popocatepec ; and of a volcano still burning; and, at the height of 1160 toises, enjoys a temperate and agreeable clt- mate; it is surrounded by canals, walks bordered with trees, aznnititude of Indian hamlets, and without doubt may be compared to the finest cities of Europe. It is distinguished also by its large scientific establishments, which may vie with several of the old continent, and to which there are none similar in the new. The botanieal garden, directed by that excellent botanist M. Cervantes; the expedition of M. Sesse, who 1s accom- panied by able draftsmen, and whose object is to acquire a knowledge of the plants of Mexico; the School of Mines, established by the liberality of the corps of miners and by the creative genius of M. d’Elhuyar; and the Academy of Painting, Engraving, and Sculpture; all tend to diffuse taste and knowledge in a country the riches of which seem to oppose intellectual culture. With instrunicnts taken from the excellent collection of the School of Mines, M. Humboldt determined the Jon- gitude af Mexico, in which there was an crror of nearly two degrees, as has been confirmed by corresponding ob- servations of the satellites made at the Havatinah. ; After a stay of some months in that capital, our travellers visited the celebrated mines of Moran and Real-del-Monte, where the vein of La Biscayna has given millions of piastres to the counts De Regla; they exammed the obsidian stones of Oyanicl, which form strata in the pearl stone and por- hyry,/and served as knives to the antient Mexicans. The whole of this country, filled with basaltes, amygdaloids, and caleareous and secondary formations, from the large cavern of Danto, traversed by a river to the porphyritic rocks of Actopan, presents phanomena interesting to the geolovuc, which have been already examined by M. dei. Rio, the pupil of Werner, and one of the most learned minera- lowists of the present day. Own. their return from. their excursion to Moran in July 1803, they undertook another to the northern part of the kingdom. At first they directed their researches to Hue- huetoca, where, at the expense of six millions of piastres, an Account of Travels Letween the Tropics. 39 en aperture has been formed in the mountain ¢f Sincec to drain off the waters from the valley of Mexico to the river Montezuma. They then passed Queretaro, by Salamanca and the fertile plains of Yrapuato, to Guanaxuato, a town which contains 50,000 inhabitants: it Is situated in a narrow defile, and celebrated by its mines, which are of far greater consequence than those of Potosi. The mine of count de Valenciana, which has given birth to a considerable town oma hill which thirty years ago scarcely afforded pasture to goats, is already 1840 feet in perpendicular depth. It is the deepest and richest in the world; the annual profit of the proprietors having nevet been less than three millions of livres, and it sometimes amounts to five or six. After two months employed 1h measurements and geo- logical researches, and after having examined the thermal waters of Comagillas, the temperature of which is 11° of Reaumur higher than those of the Philippe islands, which Sonnerat considers as the hottest in the world, our travel- ders proceeded through the valley of St. Jago, where they thought they saw in several lakes at the summits of the ba- saltic mountains so many craters of burnt-out volcanoes, to Valladolid, the capital of the antient kingdom of Michoa- can. They thence descended, notwithstanding the con- tinual autumnal rains, by Patzquaro, situated on the margin of a very extensive Jake towards the coast of the P acifie Ocean, to the plains of Jorullo, where in the course of one night in 1759, during one of the greatest convulsions which the globe ever experienced, there issued from the earth a volcano 1494 feet in height, surrounded by more than 2000 mouths still emitting smoke. They descended into the burning crater of the reat volcano to the perpendicular depth of 258 feet, jumping over fissures which exhaled flaming sulphurated hydrogen gas. Aftcr great danger, arising from the brittleness of the basaltic and sienitic lava, they reached nearly the bottom of the crater, and analysed the air in it, which was found to be surcharged i in an extra- ordinary manner with carbonic acid. From the kingdom of Michoacan, one of the most agree- able and most fertile countries in the Indies, they returned to Mexico by the high plateau of Tolucca, in'w vhich they measured the. snowy mountain of the same name, ascending to its highest summit, the peak of Fraide, which rises 2364 toises above the level of the sea: they visited also at Toluc- ca the famous hand-tree the cheiranthosteemon of M. Cer- vantes, a genus which presents a phenomenon almost unique, 60 Account of Travels between the Tropics. umique,—that of there being only one individual of it, which has“existed since the remotest antiquity. On their return to the capital of Mexico they remained there several months to arrange their herbals, abundant in gramineous plants, and their geological collections; to cal- culate their barometric and trigonometrical measurements performed in the course of that year; and in particular to make fair drawings of the geological atlas, which M. Hum- boldt proposes to publish. _. Their return furnished them also with an opportunity of assisting at-the erection. of the colossal equestrian statue of the king, which one artists M. Tolsa, overcoming difi- culties of which a proper idea cannot be formed in Europe, modelled, cast, and erected on a very high pedestal: it is srought im the simplest style, and would be an ornament to the finest capitals in Europe. »» InJanuary 1804 our travellers left Mexico to explore the eastern declivity of the cordillera of New Spain: they mea- ~ ~ sured geometrically the two volcanoes of Puebla, Popoca- ‘tepee and Itzaecihuatl. According to a fabulous tradition, Diego Ordaz entered the inaccessible crater of the former suspended by ropes, in order to collect sulphur, which may be found every where in the plains. ‘M. Humboldt discovered that the voleano of Popocatepec, on which M. Sonnensehmidt, a zealous mineralogist, had the courage to ascend 2557 toises, is higher than the peak of Orizaba, which has hitherto been considered the highest colossus of the country of Analiuac: he measured also the great pyramid of Cholula, a mysterious work constructed of unbaked brick by the Tultequas, and from the summit of which there:is a most beautiful view over the snowy summits and smiling plains of Flaxcala. * After these researches they descended by Perote to Xa- Japa, a town situated at the height of 674 toises above the level of the sea, at a mean height at which the inhabitants ‘enjoy the fruits of all climates, and a temperature equally mild and beneficial to the health of man.» It was here that, by the kindness of Mr. Themas Murphy, a respectable in- * dividual, who to a large fortune adds a taste for the sciences, four travellers found every facility imaginable for performing their operations in the neighbouring mountains. f ~ The level of the horrid road which leads from Xalapa to Perote, through almost impenetrable forests of oaks and firs, and which has begun to be converted into a magnificent -causeway, was three tumes taken with the barometer. M. Humboldt, notwithstanding the quantity of snow which 4 ~~ had. Account of Sutton Spa. 61 had fallen the evening--before, ascended. to the summit of the famous Cofre, which is 162 toises higher than the peak: of Teneriffe, and fixed its position by direct observations, He measured also-trigonometrically the peak of Orizava, which the Indians. call Sitlaltepetl, because the luminous exhalations of its crater resemble at a distance a falling star, and respecting the longitude of which M. Ferrer published very exact operations. After an interesting residence in these countries, where, under the shade of the diquidambar and amyris, are found growing the epidendrwm vanilla and convolvulus jalappa, two productions equally valuable for exportation, our tra~ vellers descended towards the coast of Vera Cruz, situated. between hills of shifting sand, the reverberation of which causes a suffocating heat; but happily escaped the yellow, fever, which prevailed there at the time. __ They proceeded in a Spanish frigate to the Mavannah to get the collections and herbals left there in 1800, and, after a stay of two months, embarked for the United States: but they were exposed to great danger in the channel of the Ba- hamas from a hurricane which lasted seven days. After a passage of thirty-two days they arrived at Phila- delphia; remained in that city and in Washington two months; and returned to Europe in August 1804 by the way of Bourdeaux with a great number of drawings, thirty five boxes of collections, and 6000 species of plants. IX. An Account of Sutton Spa, near Shrewsbury. By Dr. Evans *, Sourron.Spa ig situated within two miles south of Shrews- bury, on the slope of a gentle eminence, and close to a vil- lage of the same name, the property of the right honourable lord Berwick. ‘The spring issues from a rocky stratum of ash-coloured clay, or argillaceous schistus, containing (as appears by its effervescence with nitrous acid) ‘a small por- tion of lime; and, in its present unimproved state, yields but a scanty stream. In the neighbourhood are several beds of soft limestone and coal, the latter mineral accompanying nearly the whole course of Meole-brook. In the Sutton pits it is mixed with so large a proportion of pyrites, or sul- phuret of iron, as to be used only for inferior purposes. * This is a continuation of Mr. Plymley’s Account of the Mineral Pro- ductions of Shropshire.—See our last Number, p. 304. ‘ Fresh 62 Account of Sutton Spa. Fresh from the spring, the Sutton water is clear and co- fourless, and exhales a slightly sulphureous smell; which is most perceptible in rainy weather*. It sparkles little when poured into a glass, having no uncombined carbonic acid in its composition. When first drawn, its strong salt taste is evideatly mixed with a chalybeate flavour; but the latter is wholly lost oa exposure for a few hours, bubbles of air separating slowly, and a reddish sediment lining the sides and bottom of the vessel. Its temperature, the thermometer in the open air stand- ing at about 70°, varied from 53° to 55° of Fahrenheit ; but at another time, the thermometer in the air being at 55°, sunk as low as 48°. The infusions of litmus and red cabbage were not red- dened by it when fresh, nor greened after boiling, or long exposure; showing the absence of any disengaged acid or alkah, or of any material portion of earthy carbonate. When fresh, it imstantly struck a reddish purple with tincture of galls; but no change was produced when it had been boiled a few minutes, or exposed some time to the atmosphere. The former circumstance clearly proves the presence of iren, and the latter, that it was wholly held in solution by a fugacious acid. Mixed with lime water it deposited a reddish sediment of the carbonate of hime and iron oxide; and wyth caustic ammonia, a reddish cloud, formed by the above metal, with probably a small portion of magnesia. The saccharine or oxalic acid threw down a large and immediate prectpitate of oxalited ime. With mild kali, a copious dirty sediment was instantly formed of earth and iron, separated from their acids by the supertor affinity of the alkali. The marine and nitrous acids produced no change, or rendered it more transparent; but a few drops of sulphuric acid produced instantly a copious deposition of selenite. -Muriated barytes did not show the presence of any sul- phuric compound. A solution of acetited lead caused an immediate milki- ness in-the water, which, however, became perfectly trans- parent on the addition of distilled vinegar. ‘I'his also proves the absence of any sulphuric acid, which would have formed with the lead an insoluble compound. Characters traced * The decomposition ot pyrites, and consequent evolution of hepatic air, or sulphurated hydrogen gas, being inaproportion to the quantity of water present. . on Account of Sution Spa. 63 on paper with the above solution, and exposed to the vapour of the fresh water, became visible, of a light brown colour, by the action of hepatic air or sulphurated hydrogen gas. Some silver leaf exposed to its vapour became faintly yeilow, and a globule of bright quicksilver was slightly tarnished. But a solution of nitrated silver produced merely a white precipitate, turning blue on exposure to light; the usual effect of the muriatic acid; the quantity, therefore, of he- patie air is probably very small. A portion of the water, evaporated slowly, formed beautiful cubic crystals, which, with a drop of sulphuric acid, gave out the peculiar smell.and gray fumes of the mu- Tiatic acid. From a gallon of the water fresh from the well, were ob- tained eight ounces, or about 14.7349, cubic inches of vola+ tile contents, of which about one-eighth part extinguished flame, precipitated lime water, and was evidently carbonic acid. On applying to the remainder (which was not soluble in water by repeated agitation) the flame of a candle, slight combustion took place, and afterwards the flame burnt nearly as well as in common air. One measure of this air, mixed with an equal bulk of nitrous air in an ac- curate eudiometer, was diminished from 200 to 1.-332., while the common air of the room, added to nitrous air in the same proportion, was lowered to 1.72,°;, its purity being im a direct ratio to the degree of diminution. It was there- fore atmospheric air, with a slight mixture of sulphurated hydrogen gas, and somewhat more than the usual portion of azote, as is always the case with the air of chalybeate waters. . 4 is A wine gallon of the fresh water being evaporated to dryness, there remained of residuum 2 ounces 3 drachms, or 1320 grains; this, mixed with 12 ounces of cold distilled water, lett on the filter 12 grains of a reddish brown sedi- ment. : Caustic ammonia added to the clear: solution did not precipitate any maguesia worth collecting; but mild kali threw down a copious sediment of aérated lime, which;-on exsiccation, weighed 206 grains; and must; according to Bergman and: Kirwan, have been produced from 226 grains of muriated lime, the former containing 34%; parts of pure lime, and the latter 56.9, of muriatic acid. Subtracting this, and the twelve grains of brown resi- duum, from the whole, there remain in a gallon of the water 1082 grains of muriate of soda or common salt. The 32 grains of residuum, treated with diluted marine acid, 3 and 64 Accouni of Sutton Spa. and again precipitated by caustic ammonia, produced nearly half a grain of iron oxide, which, fused with charcoal by the blowpipe, was strongly attracted by the magnet, and assumed some degree of metallic lustre. The remaining 114 grains, insoluble in the acid, evidently consisted of clay, mixed, as appeared in a magnifier, with several crystals of silex, which were probably merely suspended, and not ine a state of solution, in the water. Grains. We have then, in a wine gallon of the Sutton water, of muriate of soda - - 1802 O Muriate of lime, with an admixture of muriated ‘ magnesia ~ See S 296 Oo Carbonate of iron - - te ans Clay and silex - - . 1k 5 Total of solid contents 1320 0 Cubic Inches. Carbonie acid - wilt - 1 805 Common air contaminated with azote and sul- phurated hydrogen gas - - 12. 685 Total of volatile contents 14 440 — ee This, in common with most mineral waters, varies not a little in the quantity and proportions of its ingredients at different seasons and in different states of the atmosphere, At one time, the caustic ammonia produced no effect on the water; at another, it deposited a very considerable por- tion of magnesia; and the hepatic smell is sometimes not in the least perceptible, particularly in dry weather*. But, however provoking these variations may be to the accurate chemist, they are luckily of little moment to the practical physician. A considerable latitude, in this respect, makes no material difference in the medicinal effects; much more depending on the quantity of the water, as a diluent and detergent, than on any other circumstance. I ain greatly indebted to my ingenious friend Mr. Du- gard, house-surgeon to the Salop Infirmary, for his kind assistance in making the above analysis. * Inthe present exposed state of the opening of the well, this must parti - cularly happen, rainy weather weakening the saline impregnation, and a warm air exhaling the gases and precipitating the iron. The well known effect of salts in operating more powerfully as they are the more diluted, compensates for the diminished strength of the solution. j The Account of Sutton Spa. 65 The Sutton water has by many been compared with that of Cheltenham, and supposed to contain nearly the same ingredients. It bears, however, a much closer resemblance | to sea water, as will be evident from the annexed table*. We have accordingly found it most beneficial in those cases for which sea water is usually recommended. It yields the same salutary stimulus to the stomach in chronic weakness of that organ, and obviates, both mildly and ef- fectually, the habitual costiveness of hypochondriac patients. Diluted in a large portion of liquid, the saline ingredients serve to wash out any acrid sordes collected in the first pas- sages, which I believe to be one of the most important uses of mineral waters. On no other principle can we explain the uniform good effects produced on the digestive organs by waters so various in the nature and proportion of their contents, and in the degree of their impregnation. Conveyed by the lacteals into the mass of circulating fluids, and thence through the different secretory organs, this water has proved highly serviceable in a great variety of glandular affections ; and, being disposed to pass off with the finer parts of the blood, promotes the excretions of urine or perspiration, according to the attendant circum- stances of clothing, temperature of the air, &c. Absorbed by the lymphatics, the acrid muriates stimulate the torpid vessels, and wash out any acrimony accumulated in conse- quence of that inirritability. We hence may readily explain their efficacy in those disorders to which the poorer classes Carbo-| Sele- | Muriate | Muriate ; Muriate Su!phate nate of} nite. | of Soda. | of Lime./of Mag-| of Lime Iron. hesia. jand Mag- nesia. Ce U — * In a wine gallon of Cheltenham ‘water, as ana- 5 40 5 0 25 480 lysed by Dr. Fo- thergil. Sutton water. E _ 1082 226 oN ih Sea water,taken up | 60 fathoms deep, in latitude of the : Canaries,and an- bec 1928 Th ao aay, alysed by Berg- man, Jt must here be observed, that the sea, being more strongly impregnated with salt in proportion to the warmth of the climate, contains on our coasts Not more than 1-30th its weight, instead of 1-23d of saline contents, Vol. 22. No. 85. June 1s05. E are 66 Account of Sutton Spa. are particularly liable, chronic diseases of the skin, and scrophula. In the former, which have so improperly been termed scorbutic *, this water has been found a very valua- ble remedy, both externally and internally applied. In the cure of scrophula, the superior merits of sea water, first introduced to publicnotice by Dr. Russel, have ever since been uniformly and universally acknowledged f. A simi- larity of ingredients would naturally lead us to expect si- miler effects from the Sutton water; and I am happy to bear testiinony, that a twenty years’ attendance at the Salop In- firmary, aswell as in private practice, has furnished ime with abundant proofs of its success in the treatment of scrophulous affections. Yet I will frankly own, that in this deceitful, and, I fear, increasing malady, the effects of medicine are frequently but too fallacious. At certain seasons of the year, and particular periods of life, the sym- ptoms will subside spontaneously, and the credit due to Nature be given to the remedy last employed. a In addition to the above properties possessed by the Sut- ton spring in common with sea water, it enjoys one evi- dent advantage, in containing iron. Though the minute portion of it, in this and many other mineral springs, may be thought inadequate to any useful purpose,—experience, our surest guide, has amply proved the contrary ; and it is now well ascertained, that small and repeated doses of this valuable metal produce far more beneficial and permanent effects on the constitution than the much larger ones for- merly prescribed. It has been variously administered, either as a calx or oxide, or as already combined with an acid solvent; but in no form has it proved so uniformly efficacious as when pre- pared by Nature herself, and’ existing as a carbonate in chalybeate springs. Winged, as it were, by its aérial acid, it pervades the remotest vessels and minutest capillaries of the system, invigorating every fibre, and rendering evacua~ tion by the saline ingredients both safe and salutary. Of the external use of this water as a cold or tepid bath, I can speak from theory alone, no such conveniences having been * \say improperly, because the real scurvy is connected with a state of the system the most opposite of any to the discases here mentioned. + It is worthy of remark, that almost every popular remedy for this com= | plaint contains the marine acid in its composition. At eng time, the muri- ated barytes was in high celebrity, and now the muriated lime is rising inte egual credit. Ihave often presciibed with success, the tinct. ferr. muriat..as eombining the tonic powers of iren with the stimulus of the acid; but I think I have found the simple marine acid full as efficacious as any of its convbinations., s+ ; : 7 : rs ‘ as Account of Sutton Spa. 67 as yet provided. But analogy fully warrants us to suppose it nearly a powerful as sea water, and applicable to the same useful purposes. In cutaneous foulnesses, in scro- phula, in chronic rheumatism, paralytic affections, and, above all, in the cachexies of young females, attended with uterine obstructions, we have every reason to expect the greatest advantages from its applications as a warm or tepid bath. This being by no mieans intended as a medical commu- nication, I have given merely a faint sketch of the virtues to. be expected from the Sutton water. The outline may be readily filled up hereafter, whenever the improved state of the Spa shall require a more accurate description of its best modes of exhibition, and the diseases to which it is appli- cable. Though its value has been Jong felt and acknowledged by the immediate neighbourhood, the spring still remains in a very tude and neglected state; an iron spout attached to a piece of wood stretched across the opening, forming the only channel for the water’s exit. Entangled in its passage to the brook below, it has produced an artificial morass, its surface being abundantly covered with ochery scum, from the deposition of iron oxide. Some time since, it was held in contemplation by the noble proprietor to erect baths, &c. for the accommodation of invalids; but the mi-’ litary avocations of the day postponed the truly benevolent institution. With the return of the blessings of peace, it will, I trust, be resumed, and an inestimable benefit thereby conferred on an extensive and populous district. The mo- rass might easily be drained by channels communicating with the brook ; and baths erected on this site would have both a constant supply from the well, and a regular dis- charge of the refuse water. While almost every fishing village on the coast is pre- aring conveniences for sea bathing, how desirable would it be to extend similar advantages to the interior parts of the island, where poverty or infirmity renders it impossible to visit the distant sea! In this county, abounding in mi- nerals, whose subterraneous wealth is beyond all calcula- tion, there is probably scarce a parish that would not supply a mineral water for the benefit of the neighbouring poor, were the springs properly examined. The air of Sutton, as might be expected from its open elevated situation, is dry and wholesome. The site com- mands a rich and highly varicgated prospect; bounded on one side by the magnificent group of Freyddin and E2 Moel ~ . 68 On the Blight or Mildew of Wheat. Moel y Golfa, with a long range of Welsh mountains rising _ in full majesty beyond them; and on the other, by their no mean rivals, the Wrekin and Stretton hills. The view of Shrewsbury, betwixt the branches of the adjoining wood, particularly when the setting sun gilds every object with his mellowest light, is greatly and most deservedly admired. The walk from Shrewsbury is pleasant and picturesque; and the neighbourhood of a reasonable and abundant market can be considered as no trifling object, when compared with the extravagant prices and scanty accommodations of many of our remote watering places. X. On the Blight or Mildew of Wheat*. Bor the most remarkable effect of the seasons of the pre- sent year (1800) is that of wheat being, in particular situations, injured by blight or mildew—in a dry summer. In this district (the Vale of Exeter) many fine looking crops were, in a manner, cut off by this malady: the straw becoming black as soot, and the grain shrivelled and light. In one instance which I particularly attended to, it was barely worth the labour of thrashing out; even at the present prices! owing, however, in some considerable de- gree, I apprehend, to the imprudence of the grower, who suffered it to stand to ripen after the blight had seized it ; while a more judicious manager in this quarter of the county +, by cutting his wheat as soon as he perceived it to be struck with the disease, preserved it, he believes, from material injury. This precaution, however, it is very probable, ninety-nine growers in a hundred did not take : and the country may have lost, in the most alarming hour of scarcity, some hundred thousand quarters of wheat by this one defect in English agriculture t ! 1804. A similar, but more universal effect took place this summer, which has likewise been characterized by dryness, at least in those parts of the island in which my observa- ' tions have been made. On my return from South Wales to London, carly in this September, wheat crops evidently appeared, by the dark * From Mr. Marshall’s new edition of the Rural Economy of the West of England. : : + Mr. Smithy of Axminster. { See the Rural Economy of Gloucestershire, for remarks on this im- portant point of management. hue On the Blight or Mildeu of Wheat. 69 hue of theirsstraw, or their stubbles, to have been more or less biizt ited 5 5 ext sepung in a few instances in Gloucester- shire, and others in Oxfordshire, in which instances only strong, yellow, healthy stubbles were observable. The cause of the disease-in the county in which I had the best opportunity of observing it (Caermarthensbire), ABER ate very evidently, to procee ed from some cold rains which fell about the middle of August. Before that time wheat crops in general looked healthy, and were beginning to change to a bright colour. But presently after a few cold wet days s the malady became obvious to the naked eye. The straw lost its smooth varnished surface, being occupied by innumerable specks, which changed in a few days, in Jess than a week, to a dark or blackish colour, giving the straw a dusky appearance *. j A gentleman of Caermarthenshire, who is attentive to agricultural concerns, is of opinion that this destructive disease may be prevented by sowing old seed ; namely, wheat of the preceding year ’s growth, jnstead of new wheat, agreeably to the practice of the Cotswold Hills of Glouces- tershire. Tam much inclined to think, that by sowing early, agreeably to that practice (see Gloucestershire, Il. 5] 4% this fatal disease might frequently be avoided, early ripe crops being, from all the observations that I have hitherto made, the least subject to its baleful effect. Corn which ripens under the hot summer sun of July, is not so liable to cold chilling rains as that which remains unmatured until the sun begins to lose its power, and the nights to increase 1n length. and coolness. A certain preventive of this disaster anid be a disco- very worth millions to the country. Until this be made, let the grower of wheat not only endeavour to sow early, but let him look narrowly to his crop during the Anes time of the filling of the grain; and whenever “he may per- ceive it to be smitten with the Wigeraes let him Jose no time in cutting it, suffering it to lie on the stubble until the straw be firm and crisp enough to be set up in sheaves, without adhering in the binding places ;—allowing it to ‘remain in the field, until the grain shall have received the nutriment which the straw may be able to impart. Where wheat has been grown on ¢ lammas land,” and the ground . ." Devonshire had its rains in the ripening season of 1800. A third in- stance of the blight of wheat succeeding rain, was observed in the same county, in 1794. And a fourth was equally obvious, in 1785, in the Mid- Jand Counties, as may be seen in the Rural Economy of that department, minute ‘oie E3 obliged 70 On the Blight or Mildew of Wheat. obliged to be cleared by the first of August, crops have beers known to be cut “ as green as grass,’”’ and to be carried off and spread upon grass Jand todry. Yet the grain has been found to mature, and always to afford a fine-skinned beau- tiful sample. Raygrass that is cut even while in blossom, is well known to mature its seeds with the sap that is lodged in the stems. Hence there is nothing to fear from cutting wheat or other corn before the straw be ripe. 1805. 4pril. That the operation of this disease is car- ried on by the fungus tribe, evidently appears from the ingenious and persevering labours of botanists*. But fungi, itis equally evident, are an effect, not the cause of the disease. They are the vermin of the more perfect ve- getables; and fasten on them, whether in a dead or in a diseased state ; but seldom, I believe, while they arein full health and vigour. Their minute and volatile seeds may be said to be every where present—ready to produce their kind wherever they may find a genial matrix. Such at least ap- pears to be the nature of the fungus, or fungi, of wheat ; for it may be liable to the attack of more than one species. In a dry warm summer, which is well known to be favour- able to the health, vigour, and productiveness of the wheat crop, the seeds of fungi are harmless, so long as the fine weather continues. On the contrary, in a cold wet season, which gives languor and weakness to the wheat plants, few crops escape entirely their destructive effects. A standing crop not unfrequently escapes, while plots that are lodged in the same field, especially in pits and hollow places, be- - come liable to their attack. And by the facts above stated, we plainly see, that even strong healthy crops may, ina few days, or perhaps ina few hours, be rendered hable to be assailed—not progressively, as by an infectious disease, but at once, as by a blast or blight. In the state of the atmosphere we are to look for the cause of the disease in a standing crop; and nothing is so likely to bring on the fatal predisposition of the plants as a succession of cold rains while the grain is forming. The coolness necessarily gives a check to the rich saccharine juices which are then rising towards the ear; and the moisture may, at the same time, assist the seeds of the fungi to germinate and take root. Thus reason and facts concur in pointing out the cause and the operation of the diseaset. The natural event pr 1s * As they are set forth in a paper just published by Sir Joseph Banks. + There appear to be reasons why corn which happens to be struck with this disease in a dry warm summer is exposed to excessive injury, as facts pretty On Stones that have fallen from the Atmosphere. 7 is too well known, and it is the business of art to endeavour to prevent it. If by cutting down the crop, as soon as it is found to be diseased, the operation can be stopped—as experience, in different instances, has shown that it may—the remedy is casy *. ; . A probable means of prevention is that of inducing early ripeness (for reasons above offered), either by sowing early, or by forcing manures, or by selecting and establishing early varieties—of wheat most especially ;—as carly varieties of pease and other esculent plants are raised by gardeners : a work which only requires ordinary attention, and whicli itis hoped will, without delay, be sct about and encou- raged by every attentive grower of wheat, and every pro- moter of rural improvements in the united kingdom. For the method of raising and improving varieties of wheat, see the Rural Economy of Yorkshire, vol. ii. p. 4. XI. On the Origin. of Stones that have fallen from the Almosphere. By Cuarctes Hurron, LL.D. and F.R.S. Dare following observations are copied from a note by Dr. Hutton on Dr. Halley’s Paper on Extraordinary Me- é 4 pretty evidently show that it is. The habits of the plants render them more susceptible of injury, their rich juices more liable to be checked, and the seeds of fungi, it is probable, are more widely, if not more plentifully, distributed, by such a state of the air, than they are by a cool moist atmosphere. * It may be asked in what manner the remedy is thus effected. But to the practical farmer the fact is all that is required. ‘To him it is equally as indifferent to know the operation of the remedy as the operation of the disease. Those who have profited by the remedy here recommended, be- lieve that it “ kills the mildew.” (See Gloucestershire, vol. ii. p- 54.) And if it shall appear that the fungus of wheat requires a free supply of air to keep it alive, orin a state of health and vigour, the effect of cutting down the crop will be explained. It will:perhaps be found, by expericace, that the closer it is allowed to lie upon the ground, and the sooner it is bound up in sheaves (provided the natura! ascent of the sap to the ear be not thereby interrupted), the more effectual and complete will be the remedy. Further, it may be suggested, on the evidence of attentive observation, that if wheat which has been attacked by this disease be suffered to remain in the field with the ears exposed, until it may have received the amclivy rating influence of dews or moderate rain (to soften, relax, and assist the natural rise of the sap), the more productive it will probably become. Sve Minutes of Agriculture, in Surrey, No.4. ‘ And it may be still further added, that grain which is cut while under ripe, is less liable to be injured in the field by moist weather, than tha which has stood until it be fully or over ripe. 4 teore, 72 On the Origin of Stones teors, given in the sixth volume of the Abridgment of the Philosophical Transactions, now publishing. Dr. peaey takes it for granted that the luminous bodies sometimes seen in the atmosphere are merely unkindled vapours. Dr. Hutton observes, that ‘* the difficulty, not to say impossibility of conceiving how any exhalations could be raised so high, ought to have hinted the idea of some other origin,” and then proceeds as follows ; “¢ Later observations have induced a belief that these Juminous appearances are allied to, if not the same as, the stones which have frequently been known to fall from the atmosphere, at different times, and in all parts ofthe earth. Several of the phaznomena are common to both. These luminous bodies are seen to move with very great velocities, in oblique directions descending ; ¢ ommonly with a loud hissing noise, resembling that of a mortar shell, or cannon ball, or rather that of an irregular bard mass projected violently through the air; surrounded by a blaze or flame, tapering off to a narrow stream in the hinder part of it; are heard to explode or burst, and seen to fly m pieces, the larger parts going foremost, and the smaller following in succession ; are thus seen to fall on the earth, and strike it with great ‘violence ; ; that on examining the place of the fall, the parts are found scaitefed about, ~ being still consi- derably warm, and most of them entered the earth several inches deep. After so many facts and concurring circum- stances, it is difficult to refuse assent to the identity of the two phenomena: indeed it seems now not to be doubted, but generally acquiesced in. And hence it is concluded, that every. such meteor-like appearance is attended by the fall of a stone, or of stones, though we do not always see the place of the fall, nor discover the stones. «© This conclusion, however, has contributed nothing towards discovering the origin of the pheenomenon, at least as to its generation in the atmosphere : : on the contrary, it seems stil | more difficult to account for the production of stones, than gaseous meteors, in the atmosphere, as well as to inflame and give them such violent motion. In fact, it seems concluded as a thing impossible to be done or conceived; and philosophers have given up the idea as hopeless. ‘This circumstance has induced them to endeavour to discover some other 2ause or origin for these phenomena. But no idea that 1s probable, or even possible, has yet been started, excepting one, by the very celebrated mathematician ‘Laplace, and that of so extraordinary a nature, as to astonish us with its novelty, and that have fallen from the Atmosphere. » 73 and boldness of conception. This is no less than the conjecture that these stomy masses are projected from the moon! a conjecture which none but an astrononver could have made, or at least have.shown to be probable, or even possible. Any ordinary person might at random utter the vague expression of a thing coming from the moon ; but no one, except the philosopher, could propose the conjecture seriously, and prove its ies lity.’ This M. Laplace has been enabled to do by strict mathematical calculation. He has proved that a mas es, “if pr ojecte sd by a volcano from the moon, with a certain velocity, of abouta mile and half per second (which is possible to be done), it will thence be thrown beyond the sphere of the moon’s attraction, and into the confines of the earth’s; the conse- quence of which is, that the mass must presently fall to the earth, and become a part of it. «To prepare the way fora calculation, and a comparison of this supposed cause with the phenomena, it will be useful here to premise a short account of the late and best observed circumstances in the appearance of fireballs, and the fall of stony masses from the atmosphere, extracted from the last published accounts of some of the more re- markable cases. [The greater part of the facts adduced by Dr. Hutton having already appeared in the Philosophical Magazine, we omit them herey and confine ourselves to the remarks he has subjoined to them.] «« Having now given a summary of the facts and evi- dence, as well with regard to the circumstances attending these singular bodies, as the ingredients they are composed of, and their outward-appearance and structure, we are now to consider what inferences respecting their probable origin may be drawn from this mass of information. And indeed we may safely conclude, as it has been inferred from the whole, by the philosophers best qualified to judge of the cireunistarices s, as follow, viz. that the bodies in question have fallen on the surface of the earth; but that they were not projected by any terrestrial volcanoes 5 ; and that we have no right, from the known laws of nature » to suppose that they were formed in the upper regions of the atmosphere. Such a negative conclusion has been thought all that we are, in the present state of our knowledge, entitled to draw. ** In this embarrassing predicament, the total want of any other possible way of accounting for the origin of those bodies, an idea has been started, perhaps at first merely at random, 74 On the Origin of Stones random, that since there is no other possible manner of accounting for them, then they must have dropped from the moon. And, indeed, this singular thought has now advanced into a serious hypothesis, which it must be allowed is unincumbered with any of the foregoing diffiicul- ties; haying ut Jeast possibility in its favour, which no other hypothesis yet proposed can claim. ‘© As the attraction of gravitation extends through the whole planetary system, a body placed at the surtace of the moon is afected chiefly by two forces, one drawing it toward the centre of the earth, and another drawing it to- ward that of the moon. The latter of these forces. how- ever, near the moon’s surface, is incomparably the greater. But as we recede from the moon, and approach toward the earth, this force decreases, while the other augments, till at length a point of station is found between the two planets, where these forces are exactly equal; so that a body placed there must remain at rest: but if it be removed still nearer to the earth, then this planet would have the superior attraction, and the body must fall towards it... If a body then be projected from the moon towards the earth, with 4 force sufficient to carry it beyond this point of equal attrac- tion, it must necessarily fal] on the earth. Such then 1s the idea of the manner in which the bodies must be made to pass from the moon to the earth, if that can be done, the possibility of which is now necessary to be considered. “© Now supposing amass to be projected from the moon, in a direct line towards the earth, by a volcano, or by the production of steam by subterranean heat, and supposing for the present those two planets to remain at rest, then it has been demonstrated, on the Newtonian estimation of the moon’s mass, that a force projecting the body with a velocity of 12,660 fect in a second, would be sufficient to carry it beyond the point of cqual attraction. But this estimate of the moon’s mass is now allowed to be much above the truth; and on M. Laplace’s calculation it appears that a foree of little more than half the above power would be sufficient to produce the effect, that is, a force capable of projecting a body with a velocity of less than a mile and a half per second. But we have: known cannon balls pro- jected by the force of gunpowder, with a velocity of 2500 teet per second, or upwards, that is, about half a mile. It follows therefore, that a projectile force, communicating a velocity about three times that of a cannon ball, would be sufficient to throw the body from the moon beyond the poit of ¢qual attraction, and cause it to reach the earth, : Now that have fallen from the Atmosphere. 75 Now there can be little doubt that a force equal to that is exerted by volcanoes on the earth, as well as by, the pro- duction of steam from subterranean heat, when we consider the buge masses of rock, so many times larger than cannon balls, thrown on such occasions to heights also so much greater. We may easily imagine too such cause of motion to exist in the moon as well as im the earth, and that ina superior deeree, if we may judge from the supposed sym- ptoms of volcanoes recently observed in the maon, by the powerful tubes of Dr. Herschel; and still more, if we con- sider that all projections from the earth suffer an enormous resistance and diminution, by the dense atmosphere of this plaret, while it has been rendered probable, from optical considerations, that the moon has little or no atmosphere at all, to give any such resistance to projectiles. “« Thus then we are fully authorised in concluding, that the case of possibility is completely made out ; that aknown power exists in nature, capable of producing the foregoing efect, of detaching a mass of matter from the moon, and transferring it to the earth, in the form of a flaming meteor or burning stone; at the same time we are utterly ignorant of any other process in nature by which the same phzeno- menon can be produced. Having thus discovered a way in which it is possible to produce those appearances, we shall now endeavour to show, from all the concomitant circum- stances, that these accord exceedingly well with the natural eflects of the supposed cause, and thence give it a very high degree ot probability. . “¢ This important desideratum will perhaps be best attained by examining the consequences of a substance supposed to he projected by a volcano from the moon, into the sphere of the earth’s superior attraction; and then comparing those with the known and visible phenomena of the blazing me- teors or burning stones that fall through the airon the earth. And if in this comparison a striking coincidence or resem- blance shall always or mostly be found, it will be dificult for the human mind to resist the persuasion that the assumed cause involves a degree of probability but little short of certainty itself. Now the chief phenomena attending these blazing meteors, or burning stones, are these: 1. That they appear or blaze out suddenly. 2. That they move with a surprising rapid motion, nearly horizontal, but a little inclined downwards. 3. That they move in several different directions, with respect to the points of the com- pass. 4. That in their flight’ they yield aloud whizzing sound. 5, That they commonly burst with a violent ex- plosion 76 ~ On the Origin of Stones plosion and report. 6. That they fall on the earth with great force ina sloping direction. 7. That they are very hot at first, remain hot a considerable time, and exhibit visible tokens of fusion on their surface. 8. That the fallen stony masses have all the same external appearance and contexture, as well as internally the same nature and com- position. 9. That they are totally different from all our terrestrial bodies, both natural and artificial. « Now these phenomena will naturally compare with the circumstances of a substance projected by a lunar vol- cano, and in the order in which they are here enumerated. And first with respect to the leading circumstance, that of a sudden blazing meteoric appearance, which is not that of a small bright spark, first seen at immense distance, and then gradually increasing with the diminution of its distance. And this circumstance appears very naturally to result from the assumed cause. For the body being projected from a lunar voleaho, may well be supposed in an ignited state, ‘Jike inflamed matter thrown up by our terrestrial volcanoes, which passing through the comparatively vacuum, in the space between the moon and the earth’s sensible atmo- sphere, it will probably enter the superior parts of this atmosphere with but little diminution of its original heat ; from which ciréumstance, united with that of its violent motion, this being 10 or 12 times that of a cannon ball, and through a part of the atmosphere probably consisting chiefly of the inflammable gas, rising from the earth to the top of the atinosphere, the body may well be supposed to become suddenly inflamed, as the natural effect of these circumstances 3 indeed it would be surprising if it did not. From whence it appears that the sudden inflammation of the body, on entering the earth’s atmosphere, is exactly what might be expected to happen. «© 9, Secondly, to trace the body through the earth’s atmosphere, we are to observe that 1t enters the top of it, with the great velocity acquired by descending from the point of equal attraction, which is such as would carry the body to the earth’s surface in a very few additional seconds of time, if it met with no obstruction. But as it enters _deeper in the atmosphere, it meets with still more and more resistance from the increasing density of the air; by which the great velocity of 6 miles per second must soon be greatly reduced ‘to one that will be uniform, and only a small part of its former great velocity. This remaining part of its motion will be various in different bodies, being’ mor: or less as the body is larger or smaller, and as it is more that have fallen from the Atmosphere. 77 more or less specifically heavy ; but, for a particular in- stance, if the body were a globe of 12 inches diameter, and of the same gravity as the atmospheric stones, the motion would decrease so, as to be little more than a quarter of a mile per second of perpendicular descent. Now while the body is thus descending, the earth itself is affected by a two-fold motion, both the diurnal and the annuai one, with both of which the descent of the body is to be compounded. The earth’s motion of rotation at the equator is about 17 miles in a minute, or 2 of a mile ina second; but in the middle latitudes of Europe little more than the half of that, or little above half a quarter of a mile in a second: and if we compound this inotion with that of the descending body, as in mechanics, this may cause the body to appear to descend obliquely, though but a hittle, the motion being nearer the perpendicular than the horizontal direction. But the other motion of the earth, or that in its annual course, is about 20 miles in a second, which is 80 umes greater than the perpendicular descent in the instance above men- tioned; so that, if this motion be compounded with the descending one of the body, it must necessarily give it the appearance of a very rapid motion, in a direction nearly parallel to the horizon, bura little declinmg downwards. A circumstance which exactly agrees with the usual appear- ances of these meteoric bodics, as stated in the 2d article of the enumerated phenomena. «° 3. Again, with regard to the apparent direction of the body, this will evidently be various, being that com- pounded of the body’s descent and the direction of the earth’s annual motion at the time of the fall, which is itself various in the different seasons of the year, according to the . direction of the several points of the ecliptic to the earth’s meridian or axis. Usually, however, from the great excess of the earth’s motion above that of the falling body, the direction of this must appear to be nearly opposite to that of the former. And in fact this exactly agrees with a remark made by Dr. Halley, in his account of the meteors in his paper above given, where he says that the direction of the meteor’s motion was exactly opposite to that of the earth in her orbit. And if this shall generally be found to be the case, it will prove a powerful confirmation of this theory of the lunar substances. Unfortunately, however, the ob- servations on this point are very few and mostly inaccurate : the angle or direction of the fallen stones has not been recorded ; and that of the flying meteor commonly mistaken, all the various observers giving it a different course, some even 78 On Stones that have fallen from the Atmosphere: even directly the reverse of others. In future, it will be very advisable that the observers of fallen stones observe and record the direction or bearing of the perforation made by the body in the earth, which will give us perhaps the course of the path nearer than any other observation. «° 4, In the flight of these meteoric stones, it is com- monly observed that they yield a loud whizzing sound. Indeed it would be surprising if they did not. For if the like sound be given by the smooth and regularly formed cannon ball, and heard at acousiderable distance, how ex- eeedingly great must be that cf a body so much larger, which is of an irregular form and surface too, and striking the air with 50 or 100 times the velocity. «© 5, That they commonly burst ‘and fly in pieces in their rapid flight, is a circumstance exceeding likely to happen, both from the violent state of fusion on their sur- face, and from the extreme rapidity of their motion through the air. If a grinding stone, from its quick rotation, be sometimes burst and fly in pieces, and if the same thing happens to cannon balls, when made of stone, and dis- charged with considerable velocity, merely by the friction and resistance of the air, how much more is the same to be expected to happen to the atmospheric stones, moving with more than 50'times the velocity, and when their surface may well be supposed to be partly loosened or dissolved by the extremity of the heat there. << 6, That the stones strike the ground with a great force, and penetrate to a considerable depth, as is usually ob- served, is a circumstance only to be expected, from the extreme rapidity of their motion, and their great weight, when we consider that a cannon ball, or a mortar shell, will often bury itself many inches, or even some feet in the earth. << 7, That these stones, when soon sought after and found, are hot, and exhibit the marks of recent fusion, are also the natural consequences of the extreme degree of in- flammation in which their surface had been put during their flight through the air. << g. That these stony masses have all the same external appearance and contexture, as well as internally the same nature and composition, are circumstances that strongly oint out an identity of origin, whatever may be the cause. ‘to which they owe so generally uniform a conformation. And when it is considered, gthly, that in those respects they differ totally from all terrestrial compositions hitherto known or discovered, they lead the mind strongly to ascribe Description of a Plough-ear. _ 79 ascribe them to some other origin than the earth we in- habit; and none so likely as coming from our neighbouring planet. «© Upon the whole then it appears highly probable, that the flaming meteors, and the burning stones that fail on the earth, are one and the same thing. It also appears im- possible, or in the extremest degree improbable, to ascribe these, either to a formation in the superior parts of the atmosphere, or to the irruptions of terrestrial volcanoes, or to the generation by lightning striking the earth. But, on the other hand, that it is possible for such masses to be projected from the moon so as to reach the earth ; and that’ all the phzen»mena of these meteors or falling stones, having a surprising conformity with the circumstances of masses that may be expelled from the moon by natural causes, unite in forming a body of strong evidence, that this is in all pro- bability and actually the case.” XII. Description of a Plough-ear which offers the least possible Resistance, and which may be easily constructed. By Mr. Jerrerson, President of the United States of America®. Tae body of a plough ought not only to be the continua-: tion of the wing of the sock, beginning at its posterior edge, but it must aiso be in the same plane. Its first function is to receive horizontally from the sock the earth, to saise it to the height proper for being turned over 3 ‘to present in its passage - the least possible resistance, and consequently to require only the suum of moving power. Were its functions confined to this, the w edge would present, no doubt, the properest form tor practice t 5 but the object is also to turn over the sod of earth. One of the edges of the ear ought then to have no elevation to avoid an useless wasting of force; the other edge ought on the contrary to * From Annales du Mustwn National @ Histoire Ni turetle, no. 4. 1802. + Lam sensible that if the object were merely to ruse the sod of earth to iven height by a determinate length of ear, “without turning it over, the f which wculd give the least resistance would not be ex: actly that of a wedge with two plane faces; but the upper face ought to be ‘curvilinear, according to ihe laws of the solid of least resistance d lescribed by mathema« tidians. But in this case the difference between. the effect of the wedge with - a curved face, and that cf a wedge with a plane face, is sd small, Vand it would Le so difficult for workmen to constru ct the former, that : rhe wedge with a. plane face ought io be preferred in practice as the first element of gur inethid! re gonstruction. (Nofe ofthe Jo ruor,) go 80 Description of a Plough-ear. go on ascending until it has passed the perpendicular, in order that the sod may be inverted by its own weight; and to obtain this effect with the least posstble resistance, the inclination of the ear must increase gradually from the mo- ment that it has received the sod. In this second function the ear acts then like a wedge situated in an oblique direction or ascending, the point of which recedes horizontally on the earth, while the other end continues to rise till it passes the perpendicular. Or, to consider it under another point of view, let us place on the zround a wedge, the breadth of which is equal to that of the sock of the plough, aud which in length is equal to the sock from the wing to the posterior extremity, and the height of the heel is equal to the thickness of the sock: draw a diagonal on the upper surface from the left angle of the point to the angle on the right of the upper part of the heel; slope the face by making it bevel from the diagonal to the right edge which touches the earth: this half will evidently be the properest form for discharging the required functions, namely, to remove and turn over gradually, the sod, and with the least force possible. If the left of the diazonal be sloped in the same manner, that is to say, if we suppose a straight line, the length of which is equal at Jeast to that of the wedge, applied on the face already sloped, and moving backwards on that face, parallel to itself, and to the two ends of the wedge, at the same time that its lower end kecps itself always along the lower end of the right face, the result will be a curved surface, the essential character of which is, that it will be a combination of the principle of the wedge, considered according to two di- rections, which cross each other, and will give what we require, a plough-ear presenting the least possible re- sistance. This ear, besides, is attended with the valuable advantage that it can be made by any common workman by a process so exact that its form will not vary the thickness of a hair. One of the great faults of this essential part of the plough is the want of precision, because, workmen having no other guide than the eye, scarcely two of them are similar.. It is easier, nxdeed, to construct with precision the plongh-ear in question when one has seen the method which furnishes the means once put in practice, than to describe the nicthod by the aid of language, or to represent it by figures. I shall, however, try to give a description of it. “Let the proposed breadth and depth of the furrow, as well as the length of the head of the plough, from its junction with Description of a Plough-ear. 8h with the wing to its posterior end, be given, for these data will determine the dimensions of the block from which the ear of the plough must be cut. Let us suppose the breadth of the furrow to be g inches, the depth 6, and the length of the head two feet: the block then (Plate I. fig. 1.) must be 9 inches in breadth at its base Jc, and 134 inches at its summit ad; for, if it had at the top only the breadth ae equal to that of the base, the sod, raised in a perpendicular direction, would by its own elasticity fall back into the - . furrow. The experience which I have acquired in my own land, has proved to me that in a height of 12 inches the elevation of the ear ought to go beyond the perpendicular 41 inches, which gives an angle of about 202°, in order that the weight of the sod may in all cases overcome its elasticity. The block must be 12 inches in height, because, if the height of the ear were not equal to twice the depth of the furrow, when friable and sandy earth is tilled it would pass the ear, rising up like waves. It must be in length 3 feet, one of which will serve to form the tail that fixes the ear to the stilt of the plough. The first operation consists in forming this tail by sawing the block (fig..2.) across from a to U on its left side, and at the distance of 12 inches from the end fg: then con- tinue the notch perpendicularly along dc till within an inch and a half of its right side; then taking diz and eh, edch equal 14 inch, make a mark with the saw along the line de, parallel to the right side. The piece abcdefg~ will fall of itself, and leave the tail cdehik, an inch anda half in thickness. It is of the anterior part alckimn of the block that the ear must bé formed. By means of a square trace out on all the faces of the block lines at an inch distance from each otler, of which there will necessarily be 23: then draw the diagonals km (fig. 3.) on the upper face, and £o on that which 1s situated on the right ; make the saw enter at the point m, directing it towards &, and making it descend along the line m1 until it mark out a straight line between & and J (fig. 5.) ; then make the saw enter at the point 0, and, preserving the direction ok, make it descend along the line o/ until it meet with the central diagonal &/, which had been formed by the first cut: the pyramid kamnol (fig. 4.) will fall of itself, and leave the block in the form represented by fig. 5. It is here to be observed, that in the last operation, in- stead of stopping the saw at the central diagonal hk /, if we had continued to notch the block, keeping on the same plane, the wedge lmnokb (fig. 3.) would haye been taken Vol. 22. No, 85, June 1805. F away, $2 Description of a Plough-eat. away, and there would. have remained another wedge kokbar, which, as I observed before, im speaking of the principle in regard to the construction of the ear, would exhibit the most perfect form, were the only object to raise the sod; but as it must also be turned over, the left half of the upper wedge has been preserved, in order to continue, on the same side, the bevel to be formed on the might half of the lower wedge. Let us now proceed to the means of producing this bevel, m order to. obtam which we had the precaution to trace out lines around the block before we removed the pyramid (fig. 4.). Care must be taken not to confound these lines, now that,they are separated by the vacuity left by the sup- pression of that pyramid (fig. 5.). Make the saw enter in the two points of the first ine, situated at the places where the latter is interrupted, and which are the two points where it is intersected by the external diagonals ok and mk, éontinuing the stroke on that first line till it reach on the one hand the central diagonal k/, and on the other the lower right cdee oh of the block (fig. 5.): the posterior end of the saw will come out at some point siteated on the upper trace in a straight line with the corresponding points of the edge and the central diagonal. Continue to do the same thing on all the points formed by the interseetion of the exterior diagonals and lines traced out around the block, taking always the central diagonal, and the edge oh ag the term, and the traces as directors: the result will be, that when you have fermed several cunts with the saw, the end of that instrament, which came out before at the upper face of the block, will come out at the face situated on the left of the latter; and all these different cuts of the saw will have marked out as many straight lines, which extending from the lower edge ok of the block, will preceed to- cut the central diagonal. Now by the help of any proper tool remove the sawn parts, taking care to leave visible the traces of the saw, and this face of the ear will be finished*. The traces * The figures 9 and 10, which we have added hereto those which ac- company Mr, Jeflerson’s memoir, were drawn in perspective by M. Valen- cienne, assistant naturalist belonging to the museum, and may serve to give’ a better idea of the result of the operation here described. Let us suppose that the saw euts the lines mk, oh (fig. 9.) in the points x and ¢, taken in the traces 7@ and fs situated in the same plane parallel to bare, and the prolongations of which on the triangles mk/ and okl are the lines ex aud ¢z; the saw must then penetrate the block remaining in the plane im ques tion until ils edge has arrived at the point s, and at the same time touch the point = of the central diagonal 4 /. The same edge of the saw will come out at some point ¥ of the face mA, so that the three points s, x,y, will be = qos 4 ee EL Description of a Plough-ear. 83 traces will serve to show how the wedge which is at the tight angle rises‘gradually on the direct or lower face of the wedve, the inclination of which is preserved in the central diagonal. One may easily conceive and render sensible the Manner in which the sed is raised on the ear, which we have described, by tracing out on the ground a parallelogram two feet long and nine inches broad, as abcd (fig 6): then placing in the point J the end of a stick 27+ imches in length, and raising the other end 12 inches above the paint ¢: (the line de, equal to. 41 inches, represents the quantity which the height of the ear exceeds the perpendicular). When this is done, take another stick 12 inches in length, and, placing it on ad, make it move backwards, and parallel to itself from ab to ed, taking care to keep one of its ends al- ways on the line ad; while the other end moves along the stick be, which here represents the central diagonal. The motion of this stick of 12 inches in length will be that of our ascending wedge, and will show how each transverse ‘dine of the sed is carried from its first horizontal position unttl it be raised to a height which exceeds the perpendicular so much as to make it fall inverted by its own weight. But to retarn to our operation ;—it remains to construct the lower part of the ear. Invert the block and make the saw enter at the points where the line a/ (fig. 9.) meets with the traces, and continue your streke along these traces until both ends of the saw approach within an mach, or any other convenient thickness, of the opposite face of the ear. When the cuts are finished, remove, as before, the sawn pieces, and the ear will be finished *. i It the same straight line. Pat if this operation be repeated in different places of the lines mk, okb from & toa certain height, the points of the face mk, at which the saw comes out, will form a curve kyn. Beyond this height the saw, always directed in such a manner that at the end of its motion it ehalltouch at the same time the edge oh and the central diagonal &1, will come out at other points situated on the posterior face abml, and the series of these points will form a second curve nd, which will meet the first in the point x, These two curves being traced out, let us suppose straight lines drawn to the places where the saw stopped each time that it touched the diagonal k/, and of which one, as already said, passes through the points $,x, 43 and let us conceive a surface touching all these straight lines, and whose limirs, on the one hand, shall be the curves kyn,nt, and om the other the edge ok, this surface, which must be ‘uncovered by sections made with @ proper instrument, will form one of the faces of the ear. The latter is res preseuted fig. 10, and the face in question is that which appears before, and whichis indicated by inlor. It willbe remarked that the angle situated to- wards / (fig. 9) on the part kedieh of the block has also been cut off bya section sade from d to r, agreeably to what will be said hereafter.—Note of the l'rench Editor. * We slall here add to this description an ilustratien similar to that given F2 ; in 84 Description of a Plough-ear. It is fixed to the plough by morticing the fore part of (fig. 5 and 10.) into the posterior edge of the sock, which must be made double, like the case of a comb, that it may receive and secure this fore part of the ear. A screw-nail is then made to pass through the ear and the handle of the sock at the place of their contact, and two other screw-nails pass through the tail of the ear and the right handle of the plough. - The part of the tail which passes beyond the han- dle must be cut diagonally, and the work will be finished. In describing this operation. I have followed the simplest course, that it may be more easily conceived; but I have been taught by practice, that it requires some useful modi- fications. Thus, instead of begining to form the block as represented abed (fig. 7-), where ais 12 inches in length and the angle at J is a right one, I cnt off towards the bot- tom, amd along the whole length de of the block, a wedge bee, the line Z being equal to the thickness of the bar of the sock (which I suppose to be 34 inch) ; for, as the face of the wing inclines from the bar to the ground, if the block were placed on the sock, without taking into the account this inclination, the side aj would lose its perpendicular direc- tion, and the side ad would cease to be horizontal. Be- sides, instead of leaving at the top of the block a breadth of 131 inches from m to m (fig. 8.), I remove from the Tight side a kind of wedge nkicpn of 14 inch in thickness; because experience has shown me that the tail, which by these means has become more oblique, as ci instead of ki,, fits more conveniently to the side of the handle. The dia- in regard to the anterior face of the ear. The thickness of the latter being determined by that of the part kcdieh (fig. 9.), or, what amounts to the same thing, by the Jength of the lines ck, d7, e/, let us first conceive that there has been traced out, proceeding from the point c, the curve cup pa- rallel tokyn, and then, proceeding from the point p, the curve p53 parallef to in. Let usnext suppose that the saw cuts the edge a/ of the face abmlt in the point 3, situated in the same planeas vf and ¢s, which plane has been taken for example in regard to the anterior face of the ear. The saw must be directed along the traces }£ and 3s in such a manner that its motion shalf stop at the term where its edge on the one hand shail touch the curve cp in the point wu situated on the trace xz, and on the other shall be situated pa- rallel to the line sxy at which the saw stopped on the other side of the ear. The edge ofthe saw will then cut the face alor in some point ¢, so situated that the straight line drawn through that point and the point w shall be pa- rallel to the straight line which passes through the point s,z,y. If you con- tinue in the same manner cutting with the saw different points of the edge al, those by which it comes out will form on the face aler a curve e493; and if through these points and those corresponding to them in the lines cp, p,. there be drawn straight lines, such as that which passes through the points s,u, and which we have taken as an example, the surface touching these straight lines, and uncovered by means of any sharp instrument, will form: with the somes 6 eholS se of the plane alor, the posterior face of the ear, suchas is represéated fig. 10.—Note of the French Editor. _ gonal \ La London Institution. 85 gonal of the upper face is consequently removed back from & toc; and we have mc instead of mk, as above. These modifications may be easily comprehended by those ac- quainted with the general principle. In the different experiments to which ears have been sub- jected to determine the quantity by which the right upper side of the block passes beyond the perpendicular, and to fix the relation between the height and the depth of the furrow, they were made only of wood; but since my ex- periments have convinced me, that for a furrow 9 inches broad and 6 in depth, the dimensions I have given are the best, I propose in future to have these ears made of cast iron. I am sensible that this description may appear already too long and too minute for a subject which has hitherto been considered as unworthy of furnishing matter of application to science; but, if the plough ts really the implement’ most useful to man, the improvement of tt can never be thought a vain speculation. However, the combination of a theory -satisfactory to the learned, with a practice which falls within the reach of the most unlettered labourer, must meet.with a favourable reception from two classes of men who render most service to suciety. XUI. Proceedings of Learned Societies. THE LONDON INSTITUTION. Ar a very numerous and respectable meeting at the Lon- don Tavern, May 23, 1805, Sir F. Baring, M.P. in the chair, the following resolutions were unanimously adopted : 1, That it is expedient to establish an institution upon a liberal and extensive scale, in some central situation in the city of London, the object of which shall be to provide— 1. A library, to contain works of intrinsic value. 2. Lectures for the diffusion of useful knowledge. 3. Readmg-rooms for the daily papers, periodical pub- lications, interesting painphlets, and foreign journals. 2. That this institution shall consist of a limited number of proprietors, and of life and annual subseribers. 3. That the interest of the proprietors shall be equal, permanent, transferable, and hereditary, and. shall extend to the absolute property of the whole establishment ; they shall be entitled to such extraordinary privileges as may be I 3 consistent 86 London Institution. consistent with general convenience, and upon them shalt devolve the exclusive right of the management of the insti- tution. 4. That the Itfe and annual subscribers shall have the same use of, and access to, ‘the institution as the proprie- tors. 5. That the qualification of a proprietor be fixed for the present at seventy-five guineas. 6. That the subscription for life be for the present twenty- five guineas. ° _7. That ladies shall be received as subscribers to the lec- tures, under such regulations and upon such terms as may hereafter be determined. 8. That as soon as one hundred persons have declared their intention to become proprietors, a general meeting of all such persons shall be convened, who shall proceed as they see occasion, to carry the plan into effect, to appoint a committee to draw up regulations for the institution, and to submit the same to a general meeting of the proprietors for their approbation. 9. That this institution be denominated the London In- stitution, for the Advancement of Literature and the Dif- fusion of useful Knowledge. ; 10. That the following persons be a committee to receive the names of such gentlemen as may desire to become pro~ prietors or life subscribers, and to conduct the progress of the proposed establishment, until a general nreeting of the proprietors can be held: Sir F. Baring, bart. M.P. John Smith, esq. M. P. J.J. Angerstein, esq. Robert Wigram jun, esq, Richard Sharp, esq. Samuel Woods, esq. George Hibbert, esq. 11, That one-third of the sums subscribed be paid on or before the 10th of June,. one-third on or before the Ist of October next, and the remaining third on or before the 1st of January next. Resolved unanimously, That the thanks of this meeting be given to those gentle- men with whom this design originated. That the thanks of this meeting be given to G. Hibbert, esq. and R. Sharp, esq. for moving and seconding the fore- going resolutions. . . Ff. Bartne, Chairman. » The chairman having left the chair, Resolved unanimously, —~ t That the thanks of this mecting be given to sir F. Baring, ~ 2.6 bart. London Institution. & 87 hart. for taking the chair, and for the ability and impartia- lity with which he has conducted the business of this day. The subscription having proceeded with unexpected ra- ree a general meeting of the proprietors will be held on’ uesday next, at the London Tavern, when the chair will be taken at one o’clock precisely. al i London Tavern, May 28, 18085. At a meeting of the proprietors of the London Institu- tion, Sir F. Baring, Bart. M.P. in the chair, Resolved, | That the subscription for the names of proprietors be now closed. That before any measures are taken for carrying the plan into execution, a petition be presented to his majesty, pray- ing that he would be graciously pleased to grant a charter to the institution. That an outline of the plan be laid before the right ho- nourable the secretary of state for the home department. That for these purposes it is expedient to elect a com- mittee of managers to continue till a charter shall be ob- tained. That the following proprietors be now elected as tempo- rary managers of this institution : Sir Francis Baring, bart. William Manning, esq. M.P,. M. P. president Wilham Heseltine Pepys, John Julius Angerstein, esq. esq. Thomas Baring, esq. Sir Charles Price, bart. M.P. Thomas Bodley, esq. alderman Harvey Christian Combe, © Job Matthew Raikes, esq. esq. M.P. alderman John Rennie, esq. Richard Clarke, F.R.S. Matthew Raine, D.D. chamberlain Richard Sharp, esq. F. A. S» George Hibbert, esq. John Smith, esq. M. P. Benjamin Harrison, esq. Henry Thornton, esq. M. P. Heury Hoare, esq. Samuel Woods, esq. Sir Hugh Ingliss, bart. M.P. Robert Wigram jun. esq. Beeston Long, esq. ‘ : That the plan , after it has reccived the approbation of a general meeting of proprietors, be laid before his majesty’s secretary of state, for the purpose of soliciting a charter for the institution. ; That the subsequent proceedings of the managers be laid before a general mecting of the proprietors for their appro bation ; and that, in the mean time, the committee of ma- nagers are hercby authorized to adopt such measures and to 88 British Institution for promoting the Fine Arts. to defray such expense as may be necessary for the esta-" blishment of this institution. That sir William Curtis, bart. be appointed treasurer to this institution, and that those gentlemen who have de- clared their intention to become proprietors and Jife sub- scribers be requested to pay one-third of their subscriptions into the banking-house of Robarts, Curtis, and Co. on account of the said treasurer. That any person neglecting to pay the first or succeeding instalments on his subscription within fourteen days after the date fixed by the eleventh resolution of the general meet- ing, shall forfeit his mght to any share or privilege in this institution. That the foregoing resolutions be printed, together with ~ those adopted at the general meeting of the 23d instant, and transmitted to every proprietor. P That the thanks of this meeting be given to sir F. Baring, bart. M.P. for his conduct in the chair. BRITISH INSTITUTION FOR PROMOTING THE FINE ARTS. At a mecting of subscribers to the plan for a British In- stitution for promoting the Fine Arts in the -united king- dom, held at the Thatched House Tavern, the 4th of June 1805, present, The Earl of Dartmouth in the chair, The earl of Aylesford John Julius Angerstein, esq. The duke of Bedford Sir George Beaumont, bart, Thomas Bernard, esq. Rt. hon. Isaac Corry, M.P. Rev. William Carr James Christie, esq. The bishop of Durham Lord De Dunstanyille Charles Duncombe, esq. M.P. Sir Wm. Elford, bart. M.P. Sir Abraham Hume, bart. Henry Hope, esq. Thomas Hope, esq. Lord viscount Lowther. Edward L. Loveden, esq. Samuel Lysons, esq. Philip Metcalfe, esq. M.P. William Morland, esq. M.P. Lord Northwick Lord Henry Petty, M.P. William Smith, esq. M.P. Richard Troward, esq. Samuel Whitbread, esq. 1 Caleb Whiteford, esq. It was moved by lord viscount Lowther, and seconded by the duke of Bedford}. and unanimously resolved, That the British Institution for promoting the Fine Arts jn the United Kingdom, under his hig most gracious patronage, do commence and take p his majesty’s birth-day, ace this day, being It ° . New Institutions in America. _ 89 It was moved by the right honourable Isaac Corry, and seconded by John Jahius Angerstein, esq. and resolved, That the earlof Dartmouth, lord viscount Low ther;. the right honourable Charles Long, sir George Beaumont, bart. sir Abraham Hume, bart. sir Francis Baring, bart. Thomas Hope, esq. William Smith, esq. and Thomas Bernard, esq. be a select committee to prepare a Uraft of regulations for the British Institution, to inquire after a local situation tor it, and to make their report to an adjourned meeting of subscribers of fifty guineas or upwards, to be held at the Thatched House Tavern, on Tuesday next, at half past twelve o’clock: the chair to be taken at one o’clock pre- cisely. It was moved by the earl of hy akontl and seconded by Henry Hope, esq. and resolved, That subsc*ibers of one guinea a year, or of ten guineas in one sum, have personal ‘admission to the rooms of exhi- bition: that subscribers of three guineas a year, or of thirty guineas in one sum, have persona! admission, and the right of introducing a friend each day: that subscribers of five guineas a year have the same personal admission, together with the nght of introducing two friends each day: that subscribers of fifty guineas have the same privileges for life, and he governors of the institution: that subscribers of one hundred guineas or upwards have the same privileges in per- petuity, and be governors of the institution, their rights to e transmissible on death, subject to, the regulations here- after to be adopted ; and ‘that ‘the institution be under the goverument of a committee of directors, consisting of the president, four vice-presidents, and twelve other persons, drom time to time to be elected by and out of the governors., . DARTMOUTH, Chairman. And the earl of Darimouth having quitted the chair, Resolved unanimously, That the thanks of the meeting be presented to his lordship for his great attention to the business of the day. Persons disposed to promote the Institution are requested to address themselves, by letter, to any of the select com- mittee; or to send their names to Mr. Hatchard’s, No. 190; Piccadilly, where the books of subscriptions are left. NEW INSTITUTIONS IN AMERICA. A lettter from New York, dated April Ist, says :— «« Among the numerous. institutions. which have been formed in this country in the course of 1504, there are three in particular in which the public take a warm interest, 49 The $0 Society of the Sciencés at Flushing. . The first is a Society of Agriculture established at Wash-~ ington under the special’ protection of government. The president of the United States, the chiefs of administration, the senators and deputies to congress, ate members of it in right of their situation. The society have already acquired 2 convenient edifice, with a field of ‘thirty acres; the com- mencement of a library, and that excellent collection of ploughs and other agricultural implements which formerly belonged to general Washington. The form of its admi- nistration, the ca zpital which it can possess (specified in bushels of wheat), and its whole organization have been fixed by its charter of incorporation, “which constitutes the society, into a political body, and ensures the existence of it for ever. The answers to the numerous questions which it sent, soon after its formation, to the societies of different countries, form, it is said, an interesting work, which will be published. The second institution is a Botanical Garden in the neigh- bourhood of New York, for which the subscribers have ob- tained also a charter. As soon as the large green-house is completed, the most curious productions of the southern provinces will be sent to it. The third institution is an Academy of Fine Arts. The first idea of this establishment originated with Mr. Living- ston, the American minister at Paris; and the public were so sensible of its importance, that long before the arrival of the plaster casts, which that gentleman presented to it, the subscribers, of twenty-five plastres each, amounted to 180. Mr. Vandeline, a native of America, who has resided se- veral years at Paris, where he has become an eminent painter, has sent to the academy some fine paintings. The president, by the sepport of the friends to this in- stitution, has purchased for it that beautiful edifice which forms the centre of the circus lately built on Hudson’s river, the large hall of which is lighted by a rotunda of cast iron entirely filled with panes of glass. It is here that Mr. Li- vingston’s plaster casts, among which there is one of the cel ebrated Laocoon, have been deposited: and seventeen pupils are already employed in making drawings from these tine models SOCIETY OF THE SCIENCES AT FLUSHING, In the meeting of November 2, last year, at the Museum in Middleburgh, the society proposed again the two follaw- ing questions, anounced in the year 1803, and to which no answers had been received. - 1 an 9500 ' . ee What. Society of the Sciences at Flushing, cep ~ I. What are the natural causes that the bottom of the harbours in Middleburgh and the Welzinge channel has been so perceptibly raised, during a series of years, by an accumulation of the mud? What are the simplest, most effectual, and least expensive means of remedying this evil? and is it possible to give a sufficient depth to these harbours and channel, and to maintain them in that state? TI. A history of the influx of the current of the sea ac-~ cording to fixed laws, and in a determinate line? What are these laws? Is the course of these currents prejudicial to our dykes and to the strand, and in what degree?) What are the practicable means of giving to this prejudicial eur- sent another direction, and of conducting it to other places, so as to obviate its destractive eflect ? The prize is a gold medal; and the answers must be sent in before the 1st of January 1806. The two following questions also, announced last year, are again proposed for the same reason as the preceding : the first for a year, the second for an indefinite time. I. As the utility of pouring out oil and other fat sub- stances during storms at sea, is established by sufficient proofs; but as the objection, that this mean may be preju- dicial to ships which follow, has not been entirely obviated, the society requires to know : : What is the physical prin- ciple of calming the waves by pouring out fat substances ? and, Can the above objection be entirely done away by an explanation of this point ? II. What was the geographical state of Zecland in re- gard, in particular, to rivers and streams, trom the earliest periods to the commencement of the government of Counts? What changes took place in it between the latter period and the end of the fourteenth century? Has it continued the same, or have evident alterations taken place? and what are these alterations ? The society has proposed also three new questions, the rize for which is a gold medal; the first to be answered efore the Ist of August 1805, the other two betore the Ist of January 1806. [. As we have no general history of the sciences and fine arts in this country, which wuld be both agreeable and useful; and as such a history is not to be expected until Histories ot each branch be composed, the society has re- solved to turn its attention to this object, and to announce one part annually as the subject of a prize question, with a view that materials may be collected fora general history, and that our countrymen may in the meap time enjoy the benetit 92 Society of the Sciences at Flushing. benefit of particular histories. But as it appears necessary to the society that the compass of this fertile subject should be treated in methodical order, for the purpose of avoiding confusion and needless prolixity, and that not only a proper distinction should be made between the sciences and fine arts, but that a proper distribution of them should be pre- viously established, according to which the society may propose its annual questions: and as it appears also that several men of letters who have written on the division of Hterature, science, and the fine arts, which, according to the opinion of the antients, are so intimately connected with each other, evidently differ, the society considers. it necessary first to propose the following question :—Is there any connection between the sciences and the fine arts? Is it possible to separate them from each other, and to distri- bute and arrange both in a regular series? What is the best order, and at the same time the best adapted to make the literary history of the various branches of the sciences and fine arts serve as materials for prize questions ? I]. As the Pythagorean philosopher, Apollonius of Ty- ana, las, by many of the pagan and other writers, been placed in the same rank with-our blessed Saviour Jesus Christ, the society requires to know: ‘* What real or pro- *bable information is to be obtained in regard to this man? ~ And what proofs of the truth of the evangelical writings can be deduced trom a comparison of the accounts given us of Apollonius by Philostratus and others, and of Jesus Christ by the evangelists; together with a comparison of the ex- ternal relation of these writers? ; III. Asthe bloody feuds known under the name of Hoekseh and Kaleljuquwsch form the prittcipal part of the carly history of this country, and as different opinions have been enter- tained in regard to various circumstances relating to them, the society wishes for a more satisfactory account of the origin of these two parties. Was it not earlier than the destructive quarrel between Margaret of Hennegau and her son William V?. What gave occasion to the appellations Hoekseh and Kabeljaauwseh ? Is the real etymology of these words established, and what was the principal object of these parties from their origin to the time when they became ex- tinct? The answers, written in the Dutch, Latin, or French languages, but in a legible band, must be transmitted, sealed up in the usual manner, to A. Dryfhout, the se- cretary, at Middleburgh, before the periods above an- nounced. c XIV. In- [93] XIV. Inielligence and Miscellaneous Articles. PRIZE QUESTIONS. 4 king of Prussia has proposed the following prize question in 1 regard to the yellow fever :— Are there suffi- ecient grounds, founded on indubitable facts, for believing that the contagion of the yellow fever can convev its infec= tion to substances destitute of life, without losing any of its «force, and in such a manner that the contact of these sub- stances can communicate the infection to» sound persons,” and by these means convey the fever to other countries? The prize for the best answer is 200 ducats, and for the second best 100 ducats. The answers must Pe written In Latin, German, or French; and transmitted to the Supe- rior College of Medicine Betate the Ist of January 1807. NEW METAL. Dr. Richter, of Berlin, has discovered in the cobalt ore of the Saxon mines a new metal which has properties com- mon to cobalt and nickel, but which differs fram both. He has given it the name of niccolun. A particular aceount of this metal has been published in Gehier’s Journal of Che+ mistry. ASTRONOMY. A table of the right ascension and declination of Ceres and Pallas. AOQOOnannruaanaa * CERES. : PALLAS. AR. Decl. N. AR. | Decl. Ss; ro) / m ™ $s h s ° 04 >s]otr 23 48 52/2 90 29 Of 21 11/3 53 94] 2 42 ME OES ane (08 We Aig ONL On ee 38 40] 21 27 | 4 2 9413 99 43 28/21 3414 6 4813 65 as aay at 4 fy? 7s [s40"g0 52 48/21 47/4 15 90/4 52 57 94{|21 53] 4 18 921/15 93 ey Wat )59 14 ae a6 | Sse an 6.3¢|92 4144 97 40/6 ‘al ii, 4fiee Ve ea at 36 eg 15 98}|92 134 35 29817 Juno is not yet visible. THE At The Tides. — Death. THE TIDES. e A correspondent remarks, that from the peculiar position of the two grand Junnnaries, the sun and the moon, on the 10th day of August next, a great increase of tide may be expected on the three following days; and that a very good opportunity will then offer to ascertain the moon’s influ- ence over the ocean, by observing the height of the tide at the principal maritime ports, particulariy at Chepstow, the Bristol channel, and at London bridge. DEATH. On the 9th of March last, at the age of about 76, the celebrated Felix Fontana, director of the Royal Museum at Florence. * He died,” says Fabbroni, “ full of glory.” Being attacked twenty-seven days before by an apoplexy, he was assisted during the fit by the duke De Bonelli, who was accidentally passing at the ime. After this accident his mental faculties were so weakened that he was scarcely able to make the necessary disposition of his property in favour of his relations, friends, and domestics. ‘The physical sciences have lost in Fontana a man by whom they were cultivated with unremitting ardour. Italy, in particular, regrets in him one of its brightest ornaments, He possessed the rare talent of an observer. He bad great boldness of conception, uncommon strength of judgment, and an obstinate perseverance in every thing he undertook. The numerous and laborious experiments he made on the poison of the viper are a proof of it, as well as those by which he threw great light on the animal cecononiy. The cabinet of Florence is mdebted to his persevering courage, thwarted by difficulties and obstacles, for the immense and valuable collection, to which there is nothing equal in Eu- rope, of wax models of every kind executed under his assi- duous and minute direction. It is also indebted to him for two wooden statues which can be taken to pieces: one of them could not be finished in his life-time, and perhaps will never be completed after his death. The reader will be astonished to learn that it consists of six thougand dif- ferent pieces, and is destined to show in its decomposition the whole system, the bowels and membranes of the human body. _ These labours, though assiduous, left him sufficient time to cultivate the other branches of the physical sciences, on which he has left works written both in. Italian andy French. Ilis style is perspicuous and elegant, valuable “qualities, List of Patents for New. Iventions. 95 qualities, in which he participated with his brother Gregory Fontana. His obsequies were celebrated with great solernnity in his parish: his body was opened before the most celebrated professors, and the features of his face were taken off by a plaster cast. His remains were deposited in a leaden coffin, with the principal circumstances of his life written on parch- ment inclosed in a metal tube closely soldered. This coffin, put into another of fir, was interred three days after under the public chapel of the noviciate of the minor conventual brothers of Sainte-Croix, close to the ashes of Galilea and Viviani, Michael Angelo and Machiavel. One of his ex- ecutors, M. Petter Ferroni, a celebrated mathematican, will make known to the republic of letters the valuable manu- scripts left by this eminent philosopher, as well as those of Gregory Fontana, found ameng his philosophical ccllec- tions. LIST OF PATENTS FOR NEW INVENTIONS. Richard Jubb, of Bridge-row, in the parish of St. George, Hanover-square, in the county of Middifesex, whitesmith ; for improvements in making and tunimy the musical instru- ment called the pedal harp, by which the half-quarter note is produced thereon with peculiar sweetuess and harmony ; and the further addition of an harmonic stop made thereto ; and also certain improvements in tuning the violin and other stringed instruments. Barrodall Robert Dedd, of Change-alley, in the city of London, civil engineer; for various improvements in the construction of fire-places, and adapting stoves and grates thereto. Joseph Bramah, of Pimlico, in the county of Middlesex, engineer; for sundry improvements in the art of making aper. Thomas Rowntree, of the parish of Christ Church, in the county of Surrey, engine-maker; for an axletree and box for carriages on an improved plan. Charles Hobson, of Sheffield, in the county of York, plater, and Charles Silvester, of the same place, chemist ; for a method of manufacturing the metal called zine into wire, and into vessels and utensils for culinary and other purposes. METEOQR- 96 Meteorologife METEOROLOGICAL TABLE By Mr. Carey, OF THE STRAND, For June 1805. Thermometer. ge 3 2 22 Nice tata ane Weather. Dense es! © Of he en Oo. & aoe S Ag i? Inches, cpg 3a \ | rc 3 yo en | ——— sl — May 27} 52°| 64°| 49°} 30-00 45° |Fair 28}-50 | 60 | 45 "15 32 |Fair 29) 51 | 64 } 52 18 72 «\Fair 30) 56 | 70 | 50 "10 | 48) {Pair 31} 53 | 61 | 44 23 49 |Fair June }} 4 56 | 44 *30 51. |Fair 9 47,| 57 | 46 98 44 |Fair 31 50 | 69 | 55 702 35 |Fair 41 46 | 56 | 46 | 29°98 34 |Cloudy 5| 47°| 57 | 49 “92 30 |Cloudy 6| 51 | 68 | 50 80 60 {Fair 7} 52 | 68 | 55 | 30°01 63 |Fair 8} 56 | 70 | 56 01 58 |Fair 9| 56 | 75 | GO | 29°82 50 |Fair 10} 61 | 66 | 55 "52 20) «6|Rain 11] 56 | 64 | 54 "48 19 |Showery ° 191 55 | 59 | 52 “06 28 |Showery 13| 54 | 68 | 54 | 30°12 45 |Showery 14/ 52 | 54 | 51 | 29°80 Oo |Rain 15} 50 | 58 | 54 “88 35 |Cloudy 16} 54 |} 64 | 56 “96 38 |Cloudy 17| 58 | 68 | 54 *92 54 |Fair 18] 56 | 63 | 55 “73 50 |Fair 19) 54 | 61 | 51 “96 38 |Showery 20} 50 | 51 | 50 95 10 |Showery 21| 49 | 54 | 49 | 30°02 25 {Cloudy 22} 50 | 58 | 50 “10 35 |Cloudy 23) 54 | 68 |} 56 | 29°90 43 |Fair 24 60-| 73 | 60 *82 60 |Fair 25| 58 | 59 | 49 -60 15 |Showery 26| 51 | 66 "85 51 {Cloudy "WN. B. The barometer’s height is taken at noon SE {9% XV. Letter to M. Lacerene, of Paris, on the Naturai ' History of North America. By Bensamin Smite Barton, M.D. Professor of Materia Medica, Natural History, and Botany, in the University of Pennsyl- vania*, Ir is a long time since I have received a letter from you. _ TI have anxiously expected one, as I am very desirous to know what progress you have made in your work on Fishes. I should, indeed, have been very glad if my leisure had permitted me to have transcribed for your use a very considerable number of facts relative to the fishes of North America, especially of the United States. These facts will, however, be published in two works in which I am en- gaged, viz. my Fragments of the Natural History of Penn- sylvania, and my Travels through various Parts of the United States. I shall only observe at present, that many of our fishes are undescribed by the different writers whom T have had an opportunity of consulting; and I believe I may assert that much very interesting matter relative to the manners, the migrations, &c. of various American species is entirely unnoticed. | I exceedingly rejoice to find, by the French and other foreign publications, that all the branches of natural history are making so much progress in your country. On this side of the Atlantic we also are doing something; as much, perhaps, as could be expected from us. The museum, founded by our countryman Mr. C. W. Peale, is very re- spectable, both for the number and value of the articles which it contains. Within the last three or four years se- veral new species of quadrupeds, or mammalia, have been discovered, and our knowledge. concerning other species has been greatly extended. You are, doubtless, well in- formed that two pretty complete skeletons of the mammoth (as it has long been called) have been discovered. One of these has been sent to Europe, and it is probable that you will have an opportunity of seeing it at Parist. I think you will have no hesitation in agreeing with me, that this mon- Strous animal must be referred to the genus elephas. As far as we are enabled to judge from the bony fabric of the animal, (and I take this to be an excellent foundation upon which to construct generic characters,) the American mam- * Communicated by the Author. + This has been published. + Mr. Peale junior, after exhibiting the mammoth here spoken of in London, returned with it for America without visiting the Continent of Europe.—Epir. ‘ ol. 22. No. 86, July 1805. G moth 98 On the Natural History of North Americas - moth was a true elephant. If in the form of his grinders, in the cnryature of his defences or tusks, and im several other circumstances, he differed considerably from the living elephants that are now known to us, those differences do no more than assure us that the American animal constituted a species distinct from the (living). elephants of Asia and Africa. The American species is unquestionably lost; for nature, it would seem, is much less anxious to preserve the whole of her created species than some illustrious naturalists have supposed. The skeletons or bones of some other large animals, more or less allied to the family of elephants, have also been discovered in different parts of North America. Among these J recognize the grinders of a species which, if not the same as the elephant of Asia, must have been (as to the form of its grinders’ at least) more nearly allied to that species than is the mammoth. The bones of another large animal have been discovered. These appear to have belonged to a species of trichechus ; perhaps to the trichechus rosmarus, or morse. We occasionally find the bones of some of the largest of the cefacea in situations very remote from tbose in which the living animals are at present to be seen. The scapula of a species of whale has been found at a considerable distance beneath the surface of the earth within the limits of the city of Philadelphia. Several years ago, the tooth of the monodon, or narwhal, was found at the distance of a few'miles from the city. These last-men- tioned facts, however, need not excite much surprise, since very extensive portions ,of the present dry country exhibit the most unequivocal proofs of an antient covering by the sea. [may add, that within the memory of our history whales were not uncommon in some of our bays and rivers, where they are no longer seen*. . You have, I suppose, heard of the large bones which have been found, in a nitrous cave, in the back parts of Virginia. Mr, Jefferson, the president of the United States, has giyen an interesting memoir on the subject of. these bones in the fourth yolume of the Transactions of the Ame- rican. Philosophical Society... He supposes them to have belonged to a large animal of the genus felis.. But these remains must.be referred to a very different family of ani- mals; to some one of the genera in the order tardigrada : the Lruta of Linneus.. I have little doubt that they and the bones found near the Plata, in South America, belong * Since the above was written a whale (balena musculus) about thirty- _ fivé feet in leagth was caught in the river Delaware, at the distance of se ~weral miles below Philadelphia, : ; ¥ to On the Natural History of North America. o9 to the same species: at all events, to an animal of the same genus; the megatherium of your countryman M. Cuvier. Many similar discoveries may be expected from the coun- tries of the United States when it shall be our lot to possess men of more leisure than we do at present; or even when our labourers shall more generally know that subjects of this kind are interesting to’ philosophers both here and abroad. : 5 In.the fourth volume of the Transactions of the American Philosophical Society, [ have given an account of a new species of dipus or jerboa, which I call dipus Americanus. I have discovered some other species of this genus, parti- cularly one, which I call dipus mellivorus. It is very de- structive to our bee-hives, eating the honey: hence the specific name. We are very rich in small animals of the order glires of Linneus. ‘There has lately been discovered a species of mus, somewhat larger than the common house- mouse, which has some of the singular habits of the opos- sum tribe. This animal is a native of Virginia and other parts of the United States. You have seen Dr. Shaw’s ac- count of the mus bursarius, or Canada rat. Either this” species (which was discovered in Canada), or another very nearly allied to it, is common in the state of Georgia and other southern parts of the United States. In Georgia it is known by the ridiculous name of salamander. I take it to be the tozan or tuza of Clavigero. If the Canada and Mexican animal be the same species, its range through the continent is very great. But 1 have long since discovered that the quadrupeds of America have a very extended geo- graphical range. I may say the same of the trees and other vegetables of this portion of the world. I must now return to some of our large animals. The animal best known in the United States by the name of e/& is essentially different from the cervus alces, or moos, and has not hitherto been described by any of your systematic naturalists. I call it cervus wapiti (wapiti being one of its Indian names), and shall give a pretty ample account of it in my Fragments, part ii., now in the press. ‘This is not the only North American cervus with which the naturalists of Europe appear to be unacquainted. But what will you say, when | inform you that there has lately been disco- vered an American species of sheep! You know that some of the missionary jesuits, who visited California towards the - end of the 17th century, inform us that they found in that country two sorts of deer, which they call sheep, from their resemblance, in make, to the sheep of Europe. The first Ge sort 100. On the Natural History of North America. sort is said to be as large as a calf of one or two years old ; its head is much like that of a stag, and its horns like those ofaram. Both its tail and hair are speckled, and shorter than a stag’s. Its hoof is large, round, and cleft like that ofan ox. ‘The flesh of this animal is said to be very tender and delicious. The second sort differs less from the sheep of Europe. Some of them are white, and others black. They are larger than the common sheep, have much more wool, which is very good, and easy to be spun and wrought *. In the History of California, by Venegas, \there is a figure of one of these animals, which the Monqui Indians, inha- biting that country, call tayét. Mr. Zimmermann seems to entertain no doubt that the taye (or tage, as he calls it,) is the same animal as the argali, or wild sheep, which in- habits the north-east parts of Asia and the country of Kamtschatkat. Mr. Pennant, though less positive, 1s of the same opinion §. ‘his, however, appears to me to be a ~ doubtful point. Venegas’s figure rather forbids the idea that the Asiatic and American animal are the same. The horns of the former are less incurvated than those of the latter. The abbé Clavigero says the taye is “ unques- tionably the ibex of Pliny, described by count de Buffon under the name of bouquetin||.”". This cannot be; judging by the figure of the Californian animal, it appears to be most essentially different from the bouquetin, which is the capra alex of Linnzus. I have latély received some additional information con- cerning the existence of a large harned animal, probably the taye, in the country adjacent to the river Missouri, the great western branch of the Mississippi. This animal is a native of the Stony mouniains, about the head waters of the Missouri. It is nearly of the size of an elk, and of the colour of a fallow deer. Its horns resemble those of a ram, but are turned, in a spiral form, like a trumpet, and are of an enormous size, some of them measuring eight (French) inches in diameter. The animal is said not to live longer than ten or twelve years, because its horns, advancing for- ward in proportion as the creature grows, finally pass the mouth in such a manner as to prevent it from eating grass, upon which alone it lives; and thus it falls a victim to its hunger. The Indians of the country make of the horns * Philosophical Transactions abridged, &c. vol. v. part 2. p.194. + Noticia de la California, &c. tomo primero, p. 43, 44, Madrid 1757. ¢ Specimen Zoologiz Geographice, &c. p. 632, 633. § Arctic Zoology, vol. i. p. 13, 14. || The History of Mexico, &c. vol. xi, p. 324. . ~ spoons On the Natural History of North America. 101 spoons and cups, some of the last of which are large enough to contain a sufficiency of food for the breakfast or dinner of four men. I have been well assured that a small species of goat, spotted black and white, inhabits the country beyond the Mississippi, to the south of the Missouri. They are said to be numerous. They have also been seen, but less plen- tifully, about the mouth of the Arkansaw river, which emp- ties itself into the Mississippi nearly in the latitude of 33° 50’. They are said to be much smaller than the common kind of goat, and extremely wild. This is possibly a va- riety of the common goat; but it is more probable that it is a distinct species, or perhaps a species of the genus ah- telope. Francis Ximenez, in his Account of New Spain, of which the country that is watered by the Arkansaw is a part, says there are in this country great numbers of rock goats, which the savages call mazatl*. These rock goats may be the same animal as the small pied goat which I have mentioned. But this is conjecture. { must add that I have received the most. undoubted information of the existence of great herds of a small horned animal in that part of New Spain which is watered by the Red river, a considerable western branch of the Mississippit. From the description which has been communicated to me, I think there can be little doubt that the animal is either a species of goat or antelope, and very probably the mazatl of Ximenez. Cla- vigero’s confident assertion, that the taye of the Monqui In- dians is the bouquetin or capra ibex, renders it probable that this last-mentioned animal is actually a native of the western parts of North America. In that case, perhaps the mazatl and the Red river animal are no other than the ibex. Cer- tain I am, that the taye cannot be the same as the ibex. The wrsus maritimus, or polar bear (ours de mer of Buf- fon), is said to be a common animal in the country adja- cent to a river called the Plata, which empties itself into the Missouri about four hundred leagues above the junction of this latter river with the Mississippi. As the Missouri, from its source to its mouth, pursues a course nearly due east, we find that the white bear is common twelve hun- dred miles west of the Mississippi, nearly in the latitude of 40°; this being about the latitude of the mouth of the Mis- souri, To the north of this the animal is much more * Francis Ximenez, as quoted by De Laet, in his Novus Orbis, p. 232. ¢ ‘he mouth of this river is nearly in latitude 31°. ‘ G3 common, ( 102 On the Natural History of North America. common. I have seen a numberof the claws of one of these animals from the Plata, and they appeared to me to be the claws of the great polar bear. If the animal which I have just mentioned should prove to be the ursus maritimus, we shall be obliged to assign to this species, in a geographical view of animals, a much more southern climate than it is supposed to exist in. And we should not forget that many facts conspire to render it probable that various species of quadrupeds were once more extensively diffused over the earth than they are at present. With respect to the very animal of which I am speaking, it would appear to have been formerly an inhabitant of se- veral countries in which it is at present unknown. It is not certain, however, that the white bear of the river Plata is the ursus maritimus. Perhaps, it will prove to be a new species, The claws which | have scen lead me to suppose that the animal to whieh they belonged could not be infe- rior in size to the large white bear of the pole. Permit me in this place to give you some account of the travels of an intelligent Indian who lately returned from a very long journey many hundred miles to the north-west of Detroit. This Indian had left his countrymen (the Mo- hawks) for the purpose of hunting, but was not inattentive to many of the objects of natural history about him., He reports, that the game of the country which he visited was the buffaloe (bos Americanus), black bear (ursus Americanus) , white bear (wrsvs maritimus ?), the latter much larger than the former, with a remarkably broad foot furnished with nails or claws as long as a man’s finger: moos (cervus alces), elk (my cervus wapiti), ‘* goats which climb up the rocks ;”? a kind of ** sheep with a hairy back, much like a deer, but furnished with long wool over the belly, and with large horns,” one of which he saw that weigbed seven pounds ; akind of deer which the French in some parts of America call capree; the fisher (I believe a species of mus- tela), the otter, the beaver, and a species of fox. He met with various kinds of birds which he had never seen before. The country which he passed through is covered with ex- tensive plains, or praires (as they are frequently called in the United States), and has very few trees. Those which he saw were principally aspen (populus tremuloides ?), birch (Letula), and a species of. pinus, or pine. During two winters that he resided in this remote part of our continent, it never rained once. The rains of the summer are very uncertain, Those which do fall are precipitated in heavy gusts. ee = Action of Platina and Mercury upon each other. 203 gusts. Our philosophical Indian travelled in a canoe, but met with no less than seventy-six carrying-places in the course of his long journey. [To be continued.} XVI. On the Action of Platina and Mercury upon each _ other. By Ricaarp CuHEneEvix, Esq. F.R.S. MRE A. &e, {Concluded from p. 35.] 1E is my intention now to exhibit one example of my po- sition, and to prove that platina and mercury act upon each other in such a manner as to disguise the properties of both. I shall therefore waive for the present all consideration of palladium, which is in fact but a subordinate instance of the case before us, When a solution of green sulphate of iron is poured into a solution of platina, no precipitate nor any other sensible change ensues, This I had already observed, and it has since been confirmed by all who have written upon the subject. But, if a solution of silver or of mercury be added, a copious precipitate takes place. This precipitate contains metallic platina and metallic silver or mercury ; some mu- riate of one or other of the latter metals is also present, as’ it is not easy to free the solution of platina from all super-. fluous muriatic acid. But these salts are of no importance in the experiment, and can be separated by such methods as a knowledge of their chemical properties will easily sng- est. The proper object of consideration is the reduction, of the platina to the metallic state, which does not happen when it is alone. I have tried to produce the same effect with other meials and platina, but I have not chserved any thing similar. It is therefore fair to conclude, that when a solution of platina is precipitated tn a metallic state by a solution of green sulphate of iron, either silver or mercury is present. The precipitation of a mixed solution of platina and silver requires no further caution than to free the salt of platina as much as possible from muriatic acid; for, as I observed in my former paper, the effect of nitrate of silver poured into muriate of platina, is to produce a precipitate, not of muriate of silver, but of a triple muriate of platina and silver. It was by this experiment that I then proved the affinity of these two metals ; for, when silver is not present, G4 muriate 104 On the Action of muriate of platina is among the most soluble salts. The best method of presenting the three solutions of platina, silver, and green sulphate of iron to each other, 1s first to pour the filtered solution of the last into the solution of platina, and then, after mixing them thoroughly together, to add the solution of silver by degrees, and to stir them constantly. In this, as in all-similar operations, the pre- sence of all acids, salts, &c. excepting those necessary for the operation, should be avoided ; and if proper proportions have been used, and all circumstances attended to, the pre- cipitation of these two metals will be very complete. But the precipitation by a solution of mercury requires to be further considered, as the state of oxidizement of this metal, as well as the acid in which it is dissolved, produces a considerable modification in the result. In the first place, the oxide, at the minimum of oxidizement, dissolved in muriatic acid, is unfit for the experiment; and even the red oxide dissolved in the same acid, or corrosive sublimate,is not the most advantageous. When a warm svlution of the latter is poured into a mixed solution of platina and green sulphate of iron also warm, as in the case of silver, these substances are brought into contact under the most favourable circum- stances. Yet even thus the precipitation is slowly and im- perfectly formed, often not till several hours have elapsed ; and sometimes a very great deficiency of weight is observed between the quantities used and those recovered directly by this method. If a solution of nitrate of mercury be used, the effect is produced more rapidly, and the precipitate is more abundant. The precipitation of muriate of platina by nitrate of silver, and the combination which ensues from it, sugcested to me an experiment which I must state at length, as from the result of it consequences are deduced which modify some of the experiments of my former paper. Tt occurred to me that a method of uniting platina and mercury without the intervention of any other metal, or of any substance but the solvents of these metals, might be accomplished as in the case of silver and platina. I there- fore poured a solution of nitrate of mercury, which solu- tion, being at the minimum of oxidizement, consequently formed an insoluble muriate with muriatic acid, into a so- lution of muriate of platina. The result was a triple salt of platina and mercury, which, when the mercury was com- pletely and totally at the minimum of oxidizement, was nearly insoluble. To procure it in this state it is sufficient to put more metallic mercury into dilute nitric acid than the nitric acid can dissolve, and to boil them together. nas tripe Platina and Mercury upon each other. 165 triple salt of platina and mercury shall be presently exa- mined. From this it is evident that to produce the union of platina and mercury, the latter being at its minimum of oxidizement in nitric acid, the addition of green sulphate of iron is superfluous. But if mercury be raised to its maxtmum of oxidizement im nitric acid the case 1s different, for no precipitation occurs till the green sulphate of iron 1s added. The most advan- tageous method for precipitating platina and mercury by green sulphate of iron is, I believe, the following. Mix a solution of platina with.a solution of green sulphate of iron, both warm, and add to them a solution of nitrate of mer- eury at the maximum of oxidizement, also warm. It is necessary to avoid excess of acid, salt, &c. in this as in all such cases. With due care the precipitation of both metals will then be complete. By comparing the experiments made with mercury and platina with those made with silver and platina, a striking resemblance will be found. This induced me to pursue the analogy, and to examine whether, independently of the ac- tion of platina; mercury had not the same property of being precipitated by green sulphate of iron as silver. Nitrate of silver is precipitated by green sulphate of iron, but muriate of silver is not sensibly acted upon by the same reagent. The insolubility of muriate of silver might be alleged as the cause of this, if I had not tried the experiment by pouring nitrate of silver into green muriate of iron, in which case all the substances were presented to each other in solution. The result was not reduction, but murfate of silver and ni- trate of iron. ‘This fact rests upon a much more extensivé asis than mere mechanical circumstances; and, if pursued with the attention it déserves, it would lead us into the wide expanse of complicated affinities and their relations. From reasoning alone we should be disposed to think that an acid, so easily decomposed as the nittic, would be suf- ficient to prevent the reduction of a metal which it can dis- solve. But on the one hand it can spend its oxygen upon a part of the oxide of the green sulphate of iron, while on the other its affinity for oxide of silver is not powerful] enough to retaig it, when there is another part of the oxide of iron present to deprive it of oxygen. But the affinity of muriatic acid for oxide of silver, one of the strongest at pre- sent known, is sufficieut to counterbalance al] the other forces. There are many other instances of the same kind. If then a solution of green sulphate of tron be brought into contact with either soluble or insoluble muriate of mercury, i06 On the Action of mercury, no reduction takes place; but if mercury, whe- ther at the maximum or the minimum of oxidizement, be dissolved in nitric acid, and green sulphate of iron be added, the mercury 1s precipitated in the metallic state. These experiments are much stronger examples than the former of the effects produced by complicated affinities. They are of importance not only as objects of general con- sideration, but in their application to the present subject. They most materially modity and are indispensable to the accuracy of the results I formerly stated; but 1 was not aware of them at the time I first engaged in the investiga- tion of this subject. I can also now explain a very material difference between some proportions observed by M. Richter and myself in an experiment which that chemist had made as a repetition of one of mine. . I had poured a solution of green sulphate of iron into a solution.of 100 parts of gold and 1200 of mercury, and had obtained a precipitate consisting of 100 of gold and 774 of mercury. M. Richter repeated, as he terms it, this expe- riment;'that is, be used 100 of gold and 300: of mercury, and obtained a precipitate weighing 102. He is surprised at the difference of weight between our results, which might be owing to his method of repeating the experiment; but the real cause of this difference lies, as 1 suppose, in my having accidentally used nitrate instead of munate of mer- cury.. I had never observed that with mercury and silver this operation had failed, and it must have been, because, on account of the known effect of muriatic salts upon those of silver, I had naturally avoided using a muriate of mer- eury. _ But the state of the nitrate of mercury which is used with a solution of gold is not indifferent. As green sulphate of iron reduces mercury when dissolved in nitric acid as well as gold, it is necessary to mix the solutions of those metals before the green sulphate of iron’ is added, in order that both may be acted upon together. If the nitrate be at the minimum of oxidizement, a precipitate is immediately formed upon mixing the solutions of gold and mercury. Calomcel is produced by the muriatic acid of the solution of gold and the oxide of mercury ; whilst the gold is reduced to the metallic staté by a portion of the oxide of mercury becoming more oxidized, and forming the soluble muriate. The precipitate consists of calomel, of metallic gold, and of a very small portion of mercury, which I believe to be in the same state; my reason for thinking so is, that I have often observed, that a glass yessel, in which I had sublimed some ‘ ¢ Platina and Mercury upon each other. 107 some of it, was lined with a thin gray metallic coat. If, on the contrary, a nitrate of mercury be highly oxidized, no precipitate nor reduction of gold takes place until the green sulphate of iron is added. But at any rate the precipitation of gold and mercury, or of silver and mercury, by green sulphate of iron, cannot be adduced as an argument to sup- port the affinity of these metals, since the effect is the same whether they are separate or united. These preliminary considerations were necessary, as well for the rectification of my former experiments, ‘as for the pursuit of my present object: and now to return to platina. Exp. 1. if a solution of highly oxtdized nitrate of mer- cury be poured into a mixed solution of platina and green sulphate of iron, the first action which takes place passes between the muriatic acid of the solution of platina andthe oxide of mercury, by which a murtate of mercuryis formed, but retained in solution. This effect makes it advantageous to use a greater quantity of the sclution of mercury than is merely capable of drawing down the given quantity of pla- tina along with itself in the form of a metallic precipitate. When this. precipitate is washed and dried, it will be found to weigh much more than the original quantity of platina ; and the augmentation of weight has no limit but those of the mercury and the green sulphate of iron employed. But even after nitric acid has been boiled for a long time and in great quantities upon this precipitate, until it no longer dissolves any part of it, there still remains more undissolved matter than the original weight of the platina used in the experiment. By exposure to heat, little more is left in ge- neral than the original platina; and sometimes even a di- minution may be observed; for, as the experiment is not attended with uniform success, it does not always happen that the whole of the platina is precipitated, but a portion of it will sometimes resist the action of the green sulphate of iron, even when sufficient mercury has been used. Be- fore the precipitate has been exposed to heat it is dissolved more easily than platina by. nitro-muriatic acid; and the solution, when nearly in a neutral state, gives a copious metallic precipitate (yet’ not equal to the quantity employed) when boiled with a solution of green sulphate of iron. Exp. 2. When a mixed solution of platina and mercury is precipitated by metallic iron, a quantity equal to the sum of the former metals is generally obtained. | After nitric acid has been boiled for a long time upon the precipitate so forined, the original weight of platina, together with a con- siderable ingrease, remains behind, nor can nitric acid apie : sIDly 108 On the Action of sibly diminish it. It yields more easily than platina to the action of nitro-muriatic acid, and its solution in that acid, when neutralized, gives a precipitate, as in the former ex- periment, by green sulphate of iron. [f this precipitate be exposed to a strong heat after it has been boiled with nitric acid, it loses a great part of its weight, and the platina alone will generally be found to remain. Exp. 3. When a quantity of ammoniacal muriate of pla- tina is treated according to the method of count Mnssin Pushkin to form an amalgam, and, after being rubbed for a considerable time with mercury, is exposed in a crucible to a heat gradually increased till it becomes violent, a me- tallic powder remains in the crucible. This powder is acted upon by nitro-muriatic acid, and when the solution is neu- tralized a copious precipitate is formed upon the addition of green sulphate of iron. This effect takes place even after the metal has been fused in the manner described in the former part of this paper. Exp. 4. If sulphur be added to the ingredients recom- mended by count Mussin Pushkin, and the whole treated as in the last experiment, the quantity of precipitate caused by green sulphate of iron in the nitro-muriatic solution of thé button which results from the operation is generally more considerable. Exp. 5. If sulphur be rubbed for some time with ammo- niacal muriate of platina, and the mixture be introduced into a small Florence flask, it can be melted on a sand-bath. If mercury be then thrown into it, and the whole be well stirred together and heated, it may afterwards be exposed to a very strong fire and melted into a button. If this be dissolved in nitro-muriatic acid, it will give a precipitate, as in the former cases, by green sulphate of iron. Exp. 6. If a current of sulphuretted hydrogen gas be sent through a mixed solution of platina and mercury, and the precipitate which ensues be collected, the metal may be reduced by heat; and with the addition of borax it may be melted into a button which will not contain any sulphur. Green sulphate of iron causes a precipitate in the solution of this metal also. Exp. 7. If to a mixed solution of platina and mercury hosphate of ammonia be added, a precipitate takes place. If this be collected and reduced, it will be acted upon by cyeen sulphate of iron poured into its solution, in the same jnanner as the metallic buttons in the preceding examples. Exp. 8. [bave already mentioned that when a solution of nitrate of mercury, at the minimum of oxidizement, is poured Platina and Mercury upon each other. 109 poured into a solution of muriate of platina, a mercurial muriate of platina is precipitated. The supernatant liquor may be decanted and the residuum washed ; if this be re- duced and afterwards dissolved in nitro-muriatic acid, it will yield a precipitate with green sulphate of iron. This method appears to me to be the neatest for combining pla- tina and mercury, as the action which takes place is inde+ pendent of every substance except the metals themselves. Exp.9. One of the most delicate tests that I have ob- served in chemistry is recent muriate of tin, which detects the presence of the smallest portion of mercury. When a single drop of a saturate solution of neutralized nitrate or muriate of mercury is put into 500 grains of water, and a few drops of a saturate solution of recent muriate of tin are added, the liquor becomes a little turbid, and of a smoke- gray colour. If these 500 grains of liquid be diluted with ten times their weight of water, the effect is of course di- minished, but still it is perceptible. I had on a former oc- casion observed the action of recent muriate of tin upon a solution of platina. If a solution of recent muriate of tin be poured into a mixed solution of platina and mercury, not.too concentrated, it can hardly be distinguished from a simple solution of platina. But if too much mercury be present, the excess is acted upon as mercury ; and the liquor assumes a darker colour than with platina alone. From all these experiments it is evident that mercury can act upon platina, and confer upon it the property of being precipitated in a metallic state by green sulphate of iron. By Experiments 1 and 2, it is proved, Ist, That platina can protect a considerable quantity of mercury from the action of nitric acid: and, 2dly, That mercury can incredse the action of nitro-muriatic acid upon platina. From Experi- ments 3, 4, 5, 6, 7, 8, it appears that mercury can com- bine with platina in such a manner as not to be separated by the degree of heat necessary to fuse the compound, since after the fusion it retains that property, which is essentially characteristic of the presence of mercury in a solution of platina. The eighth Experiment proves that the action of mercury upon platina is not confined to the metallic state ; but that these metals can combine and form an insolable triple salt with an acid which produces a very soluble com- pound with platina alone. The ninth Experiment shows that platina can retain in solution a certain quantity of mer- cury, and prevent its reduction by a substance which acts most powerfully to that effect, when platina is not present. That part of the general position, therefore, which is the 3 object 110 On the Action of object of this paper is proved, if these experiments, upon being repeated by other chemists, shall be found to be ac- curate. One or two of the above experiments scem to be im con- tradiction to some that I have stated in my paper upon.pal- ladium; for in the present examples platina protects mer- cury against the action of nitric acid ; whereas in palladium the mercury is not only acted upon itself, but it conduces to the solution of platina in the same acid. I am well aware of this objection ; but, confining myself to my present ob- ject, I shall warve all further discussion of it till another opportunity. In the mean time, however, it may be laid down as an axiom in cheinistry, that the strongest affinities are those which produce in any substance the greatest de- viation from its usual properties. When a button of the alloy of platina and mercury, as prepared by any of the above methods, is dissolved in nitro- muriatic acid, and afterwards precipitated by green sulphate of iron, the entire quantity. of the alloy used is seldom ob- tained. A considerable portion of platina resists the action of green sulphate of iron, and remains im solution. This may be looked upon as the excess of platina, and can be recovered by a plate of iron. -Hence it appears that less mercury is fixed than can determine the precipitation of the entire quantity of platina; yet in this state it can draw down a greater quantity of the latter than when it is merely poured into a mixed solution of platina, not before so treated. Indeed the whole of these experiments tend, not only to show that these two metals exercise a very powerful action upon each other, but that they are capable of great varia- tion in the state of their combination; and also, that sub- stances possessing different properties have resulted from my attempts to combine platina with mercury. This observation furnished me with a method of ascer- taining, or at least of approaching to the knowledge of, the quantity of mercury thus fixed by platina, and in combina- tion with it. The experiment, however, having been seldom attended with full success, f mention the result with the entire consciousness of the uncertainty to which it is sub- SeCti oad observed the increase of weight, which the original quantity of, platma had acquired in some cases after it had been treated with mercury, and fused into a button. J counted that augmentation as the quantity of mercury fixed. I then determined how much was precipitated by green sul- phate of iron from a solution of this alloy, and supposed it to contain the whole quantity of mercury found as above. But, Platina and Mercury upon each other. 11 But, even if attended with complete success, there is a che- mical reason which must make us refuse our assent to this estimate. It is pnssible, and not unlikely, that a portion of mercury may be retained in solution by the platina, as well as that a portion of the platuxa may be precipitated by means of the mercury. The mean result, however, was that the precipitate by green sulphate of iron consisted of about 17 of mercury and 83 of platina, when the specific gravity was about 16. With regard to palladium, lest it should be supposed that either my own observations or those of others have given me cause to alter my opinion, I will add, tbat I have as yet seen no arguments of sufficient weight to convince me, in opposition to experiment, tha: palledium is a simple sub- stance. Repeated failure in the attempt to form it, Iam too well accustomed to, not to believe that 1t may happen in well conducted operations; but four successful trials, which were not performed in secret, are in my mind a suf- ficient answer to that objection. By determining the pre- sent question we may overcome the prepossession conceived by many against the possibility of rendering mercury as” fixed, at an elevated temperature, as other metals; we may be led to sce no greater miracle in this compound than in a metallic oxide, or In water, and be compelled to take a middle path, between the visions of alchemy on the one hand, and the equally unphilosophical prejudices on the other, which they are likely to create. In the course of experiments just now related, I have seen nothing but what tends to confirm my former results; yet the only means which I can, after all, prescribe for succeeding, is perse- verance. To ascertain whether the cpinion of Messrs. Fourcroy and Vauquelin, that the new metal was the principal in- eredient in palladium, had any just foundation, | observed the methods they have recommended» for obtaining’ pure platind; but I did not perceive any difference in the facility with which either kind of platina combined with mercury. I might have added some more experiments to corrobo- rate the evidence I have adduced to prove my assertion of . the fixation of mercury by platina; but Messrs. Vauquelin and Fourcroy have promised the Institute of France a con- tinuation of their researches, and M. Richter concludes his paper with saying that he will return to the subject. From the labours gf such persons some great and important fact must issue, and J hope that the present subject will not be excluded from their consideration. The facts contained in 7 this rie On the polishing of Glass, and on this paper cannot be submitted to too severe a scrutiny ; and no judge can be more rigid or more competent than the very person who was the first to doubt my former experi- ments. But it is necessary to be observed by whoever shall think them worth the trouble of verifying, that even these experiments are liable to fail, unless proper precautions are used; that I have never operated upon less than one hun- dred grains ; and that the results which I have stated, how- ever simple they may appear, have been the constant labour of some weeks. POSTSCRIPT. \ Since this paper was written, Dr. Wollaston has pub- lished some experiments upon platina. He has found that palladium is contained m very small quantities in crude platina. This fact was mentioned to me more than a year ago by Dr. Wollaston. I have not yet seen a copy of his paper; but I shall merely observe here, that, whatever be the quantity of palladiunr found in a natural state, no con~ clusion cau be drawn as to its being simple or compound. Nothing is more probable than that nature may have formed this alloy, and formed it much better than we can do. At all events the amalgamation to which platina is submitted before it reaches Europe, is sufficient ¥o account for a small portion of palladium. ~ XVII. Observations on the polishing of Glass, and on the Amalgam used for silvering Mirrors. By B. G.Sace*. Havine been consulted in regard to the bad effects of some calces or red oxides of tron, which alter the surface of glass by rendering it dull and yellowish, I analysed these calces of iron, and found out the cause on which this defect depends. Red calx or oxide of iron, called coleothar, is employed with water for giving the last polish to glass in- tended for mirrors. Were not the oxide or caix of tin, commonly known by the name of pudty, so dear, it would be far preferable to red’ calx or oxide of iron, obtained by the decomposition of mar- tial vitriol, either by calcining it in a fire proper for disen- gaging the acid or decomposing the sulphate of iron by marine salt. In the fatter case, the red oxide or calx of iron retains a little of that salt, which is of no hurt in the LT * From the Journal de Physigue, Thermidor, an 12. ‘polishing the Amalgam used for silvering Mirrors. 113 polishing of glass: but the case is not the same if the col- cothar or red oxide of iron retains martial vitriol. This salt, when dissolved in water, is decomposed, and the yellow ochre which results from it penetrates the glass, forms a crust on it, and renders it greasy, dull, and yel- lowish ; a tint which is communicated to the image of the abject presented to the mirror. Glass when smoothed and polished does not acquire the property of reflecting objects till it has been szlvered (as it is called), an operation effected by means of an amalgam. The tin leaf employed must be of the size of the glass, be- cause, when pieces of that metal are united by means of mercury, they exhibit the appearance of lines. Tin is one of those metallic substances which become soonest oxi- dated by the means of mercury. If there remains a portion of that calx, of a blackish gray colour, on the leaf of tin, it produces a spot or stain in the mirror, and the part where it is cannot reflect objects presented to it: great care, there- fore, is taken in silvering glass to remove the calx of tin from the surface of the amalgam. The process is as follows:—The leaf of tin is laid on a very smooth stone table, and “mercury being poured over the metal, it is extended over the surface of it by means of a rubber made of bits of cloth. At the same moment the surface of the leaf of tin becomes covered with blackish oxide, which is removed with the rubber. More mercury is then poured over the tin, where it remains at a level to the thickness of more than a line, without running off. The glass is applied in a horizontal direction to the table at one of its extremities, and being pushed forwards it drives be- fore it the oxide of tin which 1s at the surface of the amal- gam. A number of weights are then placed on the glass which floats on the amalgam, in order to press it down. Without this precaution the glass would exhibit the inter- stices of the crystals resulting from the amalgam. These crystals have the form of large square laminz irregularly disposed. To obtain leaves of tin, which are sometimes six or seven _ feet in length, with a proportionate breadth, they are not rolled but hammered. ‘The prepared tin is first cast between two plates of polished iron, or between two smooth stones not of a porous nature, such as thunder stone. Twelve of these plates are placed over each other; and they are then beat on a stone mass with heavy hammers, one side of which is plain and the other rounded. The plates joined os ate first beaten with the latter: when they become ol. 22. No, 86. July 1805. H extended 114 Observations on the polishing of Glass, Sc. extended the number of the plates is doubled, so that they amount sometimes to eighty or more. They are theri smoothed with the flat side of the hammer, and are beat till they acquire the Jength of six or seven feet, and the breadth of tour or five. The small block of tin from which they are formed is at first ten inches long, six in breadth, and a line and a quarter in thickness. ats lhe When the leaves are of less extent, and thin, from eighty to a hundred of them are smoothed together. : Tin extracted from the amalgam which has been em- ployed for silvermg glass, exhibits a remarkable peculiarity. When fused in an iron pan, its whole surface becomes co- vered with a multitude of tetraédral prismatic crystals two or three lines in length and a quarter of a line in thickness. The interior of these pieces of tin, when cut with achi- sel, have a grayer tint than pure tin, which is as white as silver. The latter crystallizes also by cooling; but it re- quires care. When it begins to be fixed, decant the part which is still in fusion, and there will remain at the bottom ot the crucible beautiful crystals of a dull white colour, which appeared to me to be cubes or parallelopipedons. — The peculiar and constant crystallization of tin taken from the amalgam of mirrors, the leaden gray colour which the mass of this metal had, and the mystery made of the preparation of this tin, induced me to try whether I could not discover by analysis the substance mixed with it. Having calcined this tin in a test, it was reduced to a powder of a delicate red colour, and increased in its weight 1-25th. The magnet attracted particles of iron, the result of the hammering. It appears that this metal concurs to produce the crystallization of the tin, and the singularity exhibited by the solution of its oxide in nitric acid... At first, nothing is manifested but a slight effervescence, which soon subsides ; but four or five minutes ‘after, the mixtures become very hot, and a stronger effervescence takes place, accompanied with a great deal of nitrous gas, which is dis- engaged with an explosion, and there remains in the glass a. magma of a pale red colour. The white oxide of tin, mixed also with nitric acid at 32°, exhibits neither effervescence nor disengagement of nitrous as. .. I fused this reddish calx of tin with three parts of black flux and a little charcoal powder, and extracted from it 18 ‘pounds of tin per quintal. This metal was brittle, a pro- yperty arising from the lead, which contributes also to at- tenuate the colour of the tin. | If the lead is found there in — larger Russian Expedition to Japan: 115 larger quantity, it is because there are four-fifths of tin ab- sorbed by the alkaline flux. To determine the quantity of lead contained in the tin extracted from the amalgam of mirrors, I decomposed a hundred parts of it by four hundred parts of nitric acid at 32°. A great deal of nitrous gas was disengaged, and there remained at the bottom of the matrass a white magma. I washed it with distilled water, and evaporated the ley, which. , produced a twenty-fifth of nitrous ammoniacal salt mixed with nitrate of lead, which predominates, and forms nearly two-thirds of the saline residuum; a proportion which would indicate that the tin employed for silvering mirrors contains three pounds of lead per quintal. I now return to the mercury extracted by distillation from this amalgam. It volatilizes a portion of tin, which remains there so intimately combined that it cannot be separated by a second distillation of the mercury. I was able to disengage from it the tin by shaking the mercury with nitric acids which attacks and oxidates the tin. I washed the mercury and strained it through a piece of linen. In this state it may be employed for gilding, but when it contains the smallest quantity of tin it stains the articles. What [ have related in this memoir shows that red oxide of iron, known under the name of colcothar, is not proper for polishing glass when it contains vitriol; that the tin employed for silyering mirrors contains lead and iron; that when this tin is separated fromthe mercury by distillation this metal crystallizes with the greatest facility and without any precaution; and, in the last place, it is shown that a portion of tin is volatilized by the mercury during the di- stillation of the amalgam, and that it cannot be separated but by the nitric acid. XVII. Extract of two Letters from Captain Von Kru- SENSTERN, Commander of the Russian Expedition to Japan. dated the Harbour of St. Peter and St. Paul, July 19, and August 20, 1804. {Concluded from p, 13.] Tie Frenchman is now at Kamtchatka. I shall mention hereafter by what accident he remained on board the ship. This man is a singular phenomenon: he had forgotten his own name, those of his father and mother, and that of the place from which he came. He sung to us some patriotic He songs, 116 Russian Expedition to Japan. | songs, which he, however, mutilated very much. He at length recovered his French; and then remembered that he came from Bourdeaux, that his father was named John Cabrit or Joseph Cabrit; but instead of Cabrit he some- times said Cadiche ; and Roberts called him John. As he now saw that he could no more get back from the ship to his dear Nukahivah, he exhibited a wonderful mixture of melancholy and levity. Sometimes he would fall a-laugh~ ing, and afterwards sayin a whining tone: Moi beaucoup triste la madame, la mademoiselle. He had a wife who had- brought him a son or a daughter; and his father-in- law had given him a house with coco-nut and bread-fruit trees. It was curious to observe in what manner his ideas were expanded. One time, recollectiny some of his joyful scenes at Bourdeaux, he suddenly exclaimed, as if he had seen a vision,— Beaucoup de chandelles, beaucoup de violons, beaucoup de musique, les madames, les mademoiselles ! As may be readily supposed, we did not know what this meant; but we at léneth conceived that he might remember his hav- ing been at the play. He still thought of Nukahivah, and he-has not yet given up the idea of returning thither. He soon recovered his French, and made use of expressions which he could not have learnt from us, as we were not ac- quainted with them, sueh as the names of the different sails, &c. He often afforded us subject of laughter. Hay- ing asked him in what the natives of Nukahivah showed acuteness, he replied,~-Beaucoup d’esprit, ill ne couchera pas avec sa soeur, un autre baisera sa soeur et il couchera avec un autre fille, beaucoup d’esprit ! 1 here quote his own words. From these expressions it is seen that certain de- grees of consanguinity are in that island forbidden. I once gave him a good new shirt, but he immediately bartered it with one of the sailors for a red flannel jacket. When Pb told him that he had suffered himself to be cheated, he would not listen to me. As soon as he went on shore he put on the jacket, and with feathers on his head and a lance in his hand danced on an eminence, capering and jumping in a most extraordinary manner. Several of the natives then wished to accompany him, in order that they might go to war. He now showed them how they would. creep along and. conceal themselves behind bushes-or among the grass, and in what manner, when they fell in with any of the enemy, they would beat them and carry them off. Te seemed to be inspired with an enthusiastic spirit of war- fare, and extolled what eives these people so much pleasure. When asked whether he would himself eat any of the Si ° Russian Expedition to Japan. 117 of their enemies, he replied ‘* No, I have never done so :” he added, that the sight of others eating it had made him sick: he had killed three enemies, but had exchanged them for swine. The latter circumstance was confirmed by the Englishman. From this it appears that war among these people is a kifd of amusement, as hunting is among us. Ketenue is very averse to it, but is not able to prevent it. When I asked him why he. did not prevent it, Joseph an- swered, When five or six seize an enemy and put him to death, they carry him into the woods and there devour him. How then can Ketenue prevent it? Having spoken so much of their enemies, I must now mention who they are. All the islands in the South Seas are exceedingly mountainous, as is the case with the Marquesas and Nukahivah : the fer- tile and inhabited valleys are separated by high, steep, and barren mountains. Tapeka Ketenue was the chief man at the Bay of Tayohoz, where we lay at anchor; and other valleys are in the possession of other chiefs. With the in- habitants of many of these valleys the former are in a state of warfare. These are their enemies. The hostile parties are always separated ‘by high mountains, and at each expe- dition these must be clambered up. They have few war canoes, for the purpose of undertaking expeditions by water. Ketenue’s daughter was married to the chief of another bay, and, as she was conveyed thither by sea, it was agreed that during her life no war should be carried on at sea with the inhabitants of that bay. Should she come to Tayohoz on a visit and die, her spirit would remain there, tad no naval battle could be fought between the two bays. Hogs are killed on all their festivals and occasions of solemnity. When any one dies a banquet must be given ; and therefore it is so difficult to procure any of these animals. Their god Atua is the body of their deceased priest. The body is first besmeared with coco-nut oil, and toasted in the sun till it becomes hard and dry: it is then wrapped up in a piece of cloth, and being suspended in the priest’s house, in the morai or wahitaabo, becomes their god. Sometimes it is consulted as an oracle; and Joseph is still convinced that the answers it gives are infallible. Roberts firmly be- heves that the natives here are well acquainted with the art of witchcraft. Joseph considers himself as an adept in it, and asserts that by means of certain knots he can make a sick person so i!l that he must dic. I had the courage to suffer him to try the experiment on myself; but untortu- nately there is here no morai, where the string with the knots upon it must be buried. When the priest dies, war H 3 immediately eee Russian Expedition to Japan. immediately ensues; and they then endeavour to find out some enemies, who are either eaten or merely hung up, I da not exactly know which, in honour of the deceased. When the priest. dreams that he has eaten human flesh, he tells whether the person was tatooed or not, and gives nearly a correct description of him. A state of war now ensues ; that is to say, some of them creep towards the enemy ta endeavour to find a person answering this description, and, according to their opinion, the person of whom the priest . dreams, will always tall into their hands; the person is al- ways a kikino, that is, one who has broken taaboo, The Frenchman had been in several of the Marquesa islands ; first in Santa Christina. The people, manners, and cus- toms, are in all the same. On the 18th of May we took advantage of a light breeze to get out of Anna Maria or Tayohoe Bay. On this oc- casion the Frenchman remained on board. We had for- gotten to send him on shore. When we were out in the open sea, the wind was so strong and so fresh, that, though an excellent swimmer, he would not venture to swim back to the shore, Our passage to the Sandwich islands, as is always the case between the tropics, was pleasant and agree- able, the weather being always fine, On the Sth of June, in the afternoon, we were opposite to the south-east coast of the island of O-why-he, at the distance of about three or four Italjan miles, The natives brought off to us a dish of sweet potatoes and a small hog ; one of the women also came on board the ship, Towards night we stood off from the land, and next day were at the southern extremity at about the same distance as the pre- ceding day. We purchased a small hog; a larger one they carried back with them becayse we could give them no cloth, of which they wanted a large quantity. A frock ‘which we offered them was too small for them. On knives, axes, and mirrors, they set no value; and therefore we supr posed that they must have been supplied with all these arti- cles by the English and the Americans. Several of them spoke a little English : a woman who was among them held out her hand tous, and kept continually repeating,—‘* How do you do? Very well,” On the 10th we were opposite to the western coast. We here saw the large mountain Morno Roa, which is said to be as high as the Peak of Teneriffe. As the summit of it is very broad, it does not appear to have the same elevation. We were a great way from the shore, and no boats came Poh hot Coa We Russian Expedition to Japan. 119 We now parted from the Neva and proceeded south- west, while the Neva determined to come to anchor in Karakakua Bay, where the celebrated Cook was killed. The natives of the Sandwich isles are more industrious than those of the Marquesas. Their canoes are excecdingly neat, and fully secured from being overset, by outriggers applied tothem. The sea was very rough at the time when they visited us; but they suffered no damage. The cloth which they make of the bark of the paper-mulberry is very beautiful, and of bright colours. The broad girdle worn by the woman was of a lively red colour. The men are smaller than those of the Marquesas, and seem to be artful and deceitful people. In most of them the incisor teeth are wanting. These they are very careful to knock out. The women are larger and more clegantly made than those of the Marquesas. “Both sexes have a darker colour than the natives of the Marquesas, though the climate in the latter is much warmer. Many of them also are tatooed, but not so strongly: some of them had several figures on their legs; and one had the figure of a musket and bayonet on the arm. This is nearly the whole of the intercourse we had with them. When we return from Kodjak we shall pay them another visir. To be sure of the trade wind we again approached the equator, and proceeded west on the parallel of 17°. The weather was fine, and the wind as favourable as possible ; so that we advanced more than two degrees every day. As we turned towards the north we began to be sensible of the effects of custom; the temperature of 18° of Reaumur was somewhat disagreeable to us. I asked Joseph whether it was ever so cold in Nukahivah. ‘¢ Jamais, jamais,” re- plied he. In the latitude of 36° north, and longitude 191° west from Greenwich, we proceeded some degrees towards the west, but saw nothing of the Silver islands. On the evening of July 13 we saw the high mountains of Kamtchatka. On the 15th we entered the harbour of St. Peter and St. Paul, and came to anchor. When we saw the fine prospect which here presented itself, we could not believe our own eyes: there was still a little snow to be seen on the summits of the highest mountains, but the Jower ones were covered with beautiful verdure; and the smell of the birch-trees was perceived on board the ship. The only scorbutic patient in the ship. was sent on shore, where he soon recovered. We were extremely fortunate, when it is considered that we were five months at sea, and for ihe last four months had lived entirely on salted provi- 4 sions. 120 Russian Expedition to Japan. sions. Our sour crout had become spoilt at St. Cathe rine’s, and was thrown overboard. A pthisicky German cook, who would not remain in Brazil though every kind of support was offered to him, died three days after we had crossed the line, The heat of Nukahivah had entirely ex- hausted him. He would certainly have died in Enrope, but perhaps some months later. The arrival of the Nadeshda was a very fortunate circum- stance for this country. The beneficial effects of it are al- ready felt by all Kamtchatka, Many necessary articles could no longer be obtained, and others had risen to a most ex- orbitant price. This evil has been remedied. Brandy, for example, at certain times had been sold for fifty rubles per can: from eighteen to twenty rubles was the common price; and at present it is six rubles: all other things were in the same proportion. The ambassador Resanof, and general Koschelef, a fine young man, settle the price, and superintend all public transactions. | In regard to the Kamtchatdales I have little to say ; few of them now remain. All those in Paratunka have become extinct, Those left have, in a great measure, lost their originality of character: the only thing by which they are at present distinguished is, that they are excellent bear- hunters. There are here a great many bears, which feed on fish, Iwas told that above forty of them were seen round a whale lately cast on shore: this, perhaps, may be exaggeration, but it is nevertheless certain that they are very numerous. I lately was present at an original Kamtchatdale dance : it represents the courtship of a bear, The bear, animated by the passion of love, gesticulates with great violence; emits wild tones, which die away almost in the throat; the female, by no means insensible to these strong indica- tions of tenderness, answers with a kind of growling and snarling ; her motions, however, were much more mode- rate. The whole was exceedingly disgusting, and a-re- main, no doubt, of the antient Schamans, as well as the dance of birds. We lately received a visit on board ship from two of the natives. Ag we gave them a good reception they were highly pleased, and praised us much; telling us that we were very good men, just like the Kamtchatdales. All the houses here, without exception, smell Jike stock- fish, The degree of the smell is determined by the greater or less cleanliness of the inhabitants. The people eat scarcely any thing but fish. The howling of the dlogss’ ; which Russian Expedition to Japan, ae which are a kind of shepherds’ dogs, is heard here almost every evening. They are very numerous ; but tame, and never hurt any one. This harmlessness of disposition arises from their being fed by all the inhabitants ; for every person who catches fish, as soon as the nets are drawn, throws a few to the dogs, which are accidentally present, and there- fore they are fond of fr equenting the sea shore. In winter they are chained up. Captain Clark’s grave is below an old birch tree. The epitaph La Perouse caused to be engraved on a plate of copper, and under it was. inscribed, pana By the order of count de la Perouse, chef d’escadre,” &e. The copper plate was fixed up with nails, but was nevertheless stolen. After this circumstance a voice was heard every night demanding it back ; and it was at length restored. ‘Tt is not nailed up at present, yet no person touches its The ship Slava Rossic, in which Billings performed his voyage, lies here sunk in the harbour. Great complaint having been made here that there was no establishment for taking care of the sick, and that many perished for want of proper assistance, general Koschelef proposed a subscription, which was seconded by the am- bassador ; and each having subscribed 1000 rubles, the sum of 4000 was collected in the course of less than an hour, On its being remarked that. this circumstance would give great satisfaction to the emperor, the enthusiasm became general. AJ] this was done on board the ship, and it is not improbable that something has been collected on shore, I shall send you a further account of Kamtchatka when I return from Japan, Our water continued sweet, and never became corrupted; for this we were indebted to the care of the captain, who always caused the casks to be charred. ‘When at Copen- hagen he had read in a journal, edited by Pfaff and Fried- lander, that water would keep a long time uncorrupted in’ charred casks; and this we have found perfectly confirmed. The following trait will serve to show Joseph’ s way of thinking, and what he considered allowable in Nukahivah. When the ship was unloaded here, it was found that a great deal of mischief had been done by the rats; they had emp- tied several pipes of wine, or at least gnawed the casks in such a manner that the wine had run out. As the whole almost of our provisions were on shore, they became very. restless, and appeared in great numbers. | recollected that ] had among my medicines mux vomica, some of which I mixed 122 Russian Expedition to Japan. mixed with dough. When Joseph heard that this would destroy rats, he asked if it would kill men also. Having answered in the affirmative, he requested me to give him some of it. On asking him what he meant to do with it, he replied, that when he returned to Nukahivah and ate witht any of the natives, he would mix it privately with the food, so that the person should die. When I represented to hin the atrocity of this idea, and told him that he might perhaps poison us also, he replied, that it would be highly criminal to poison us, but that in Nukahivah it was nothing; the natives, he said, bewitched each other in such a manner that they must die, and poisoning was not worse. It is mentioned in Cook’s Voyages that he frequently interchanged names with some of the “kings or chiefs. Cook, in all probability, was taabooed by assuming the king’s name; and the king took Cook’s name in order to be taabooed agaimst the “English. But Cook, perhaps, laboured under a mistake ; for Ketenuc gave his name to captain Krusenstern, but: assumed none in return. The same cus- tom prevails in almost all the islands of the South Sea: it is to be supposed that Cook and other navigators must neces~ sarily have fallen into many mistakes; for of this circum- stance we should have been entirely ignorant, bad it not been for the information given to us by Joseph and Roberts. There bave been English missionaries at Otaheite, Santa Christina, and even in Nukahivah. The one who was in Nukahivah was called Crook, and had the name of Kete- nue’s son: he was not able, however, to convert any of the natives, and soon quitted the island. These missionaries will have it in their power to communicate the most certain information respecting the natives of the islands in the South Sea, for some ‘of the accounts given by others are contradictory. I have had an opportunity of making a very droll observa- tion. Wherever we touched where we did not understand the language, each person endeavoured to remedy that de+ fect by ‘the. language of which he understood the least. One of our naturalists spoke Russian to the inhabitants of Nu- kahivah; the sailevs spoke Portuguese: but in Brasil they bad spoken English amd Danish. A droll fellow, of the name of Kurganon, endeavoured to make his way with German, of which he understood only two words: MWollen sie? Will you? The Kamtchatdales of Paratunka are said to have had the vellow fever. The under surgeon here called it Felrts Ame- - ricana On the manufacturing of some Oxides of Mercury. 193 ricana flava. In inquiring the ‘symptoms I committed a fault; for, instead of waiting for his answer, I said, «* Were they not so and so?” And all his answers were in the af- firmative. I need hardly remark, that on our arrival here we differed one day in our reckoning : to us on board the ship it was Sunday ; on shore it was Monday. XIX. Extract from a Memoir of M. PaysseE, principal Preparer of Medicines at the Camp of Utrecht, on the manufacturing, on a large Scale, of some Oxiiles of Mercury. By M. ParmMEntTixr * M. PayssE, to whom we are indebted for the following information, in regard to the manner in which the Dutch prepare, on a large scale, red sulpharated oxide of mercury and red oxide oF mercury by nitric acid, does not lose a moment to take advantage of his stay in Raid: He seizes every opportunity of visiting the manufactories, so nume- rous in that eountry, as well as the cabinets of the curious, which may contribute towards his instruction. The diff- culties of every kind which he encountered before he could get admission to these manufactories are a sufficient proof of his ardent zeal for the arts and sciences; but amidst the disappointments which the traveller experiences on his route while making researches, he often obtains an indemnity for the care he takes, and the sacrifices he makes, when he is so happy as to meet with any objects proper for seconding the desire he has to add to his knowledge, and to enrich his country with the discoveries of the industrious nations he “is so fortunate as to visit. Such is the advantageous situa- tion of M. Payssé, who has already procured us detached information in regard to many interesting objects. The reader will easily form an opinion of them from the follow= ing extract from the last memoir addressed to me by this chemist. Red sulphurated Oxide of Mercury (Cinnabar). This matter is prepared only in two manufactories at Amsterdam. The most considerable is that which belonged to the late M. Brand. M. Payssé assisted at an operation in which 800 pounds were prepared, divided into two por- tions. He observed all the details with every possible at- * From the Annales de Chimie, No, 152. . tention } 124 On the manufacturing, on a large Scale, tention; and, after comparing them with those published by. M. Tuckert in the fourth volume of the Annales de Chi- mie, for the year 1790, he found only a very slight differ- ence; so that the description of the chemist of Amsterdam may be considered as nearly exact. The following is what he has omitted. He does not speak of the duration of the flame, nor of its colour, which arises from the combustion of the union of the sulphur and mercury previously pre- pared and introduced into the apparatus. This flame, the disengagement of which is exceedingly rapid, exhibits the most various colours ; first of a bright dazzling white, rising at least twelve decimetres above the dome of the furnace ; then yellow and white orange yellow ; blue and yellow, giv- ing’ birth to the green and violet shades, and at last to blue and to green. Its disengagement is overcome towards the end by a sort of register of iron plate, when it no longer rises but to the height of some centimetres, and its colour becomes indigo or sky blue. The apparatus is then her- metically sealed, and luted on the outside with 4 mixture of clay and sand. There is no doubt, from the loss experienced in the result of the operation, that the shades so various of this flame, the disengagement of which lasts about half an hour with 200 kilogrammes of matter, arise from the union of the sulphur with varied proportion of mercury at different de- grees of oxygenation. The 400 kilogrammes, or about 800 pounds of red sulphurated oxide of mercury, were reduced to 379 or 322 kilogrammes, or between 738 and 745 pounds, which form a loss of from 27 to 31 kilogrammes, In speaking of the vessels employed in this operation M. Tuckert forgot also to describe exactly their form. The principal vessel is not a jar, but a kind of crucible, round which the heat circulates, and which has over it an iron > dome, through the summit of which the matter is intro- duced after the crucible has been brought to a red heat. The success of the operation depends in an essential manner on the management of the fire during the sublimation. The fuel employed is turf, and, according to M. Payssé’s ob- servation, none 1s better calculated for the purpose when a constant and moderate heat is required. This uniformity of temperature during the thirty hours of heat maintained in the furnace is, no doubt, one of the causes which contri- butes most to the success of the operation. Besides, expe- rience, according to the acknowledgment of the workmen, speaks in favour of this opinion. When red sulphurated oxide pf mercury is ; separed, a very of some Oxides of Mercury. 195 very large quantity of it is pulverized to be converted into vermilion. This preparation is still a secret among the Dutch. In every work of chemistry, however, the process for obtaining it is described. They merely say that the cinnabar is to be reduced to powder, then washed in water and dried. This method, which M. Payssé often employed, gave him always, indeed, for product a very beautiful red powder; but it must be allowed that it is inferior ‘1 beauty and the splendour of its colour to that manufactured in Holland. China furnishes painting with a kind of red sulphurated oxide of mercury in powder (vermilion), much more esteemed than that of the Dutch. it is of a beautiful red colour, with a shade, the splendour of which nothing can equal. For some years, therefore, the Dutch have endea- voured to imitate it. M. Payssé saw some prepared in the manufactories of that country, the process of which is an- other mystery. This oxide rivals in beauty that of the Chinese. He is of opinion that in a little time it will at- tain to the same degree of perfection. As he was not able to obtain any information in regard to the means employed to imitate this particular preparation, and suspecting that the splendour of the Chinese sulphurated oxide of mergury could arise only from the state of oxygena- tion, more or less advanced, in which the mercury may be in that combination, he made the following trial :—He took a hundred parts of Dutch red sulphurated oxide of mercury, and having pulverized them, put them into a glass capsule sheltered from the impression of the solar rays, and covered this powder with some cubic centimetres of pure water, taking care to stir the mixture for a month with a glass tube. At the end of seven or eight days he saw the oxide sensibly change, and assume a very agreeable shade. Durin about twenty-five days the splendour of the red arte: adually and acquired the utmost beauty. Having ob- served that the matter remained in the same state, and that it no longer underwent any apparent change, he decanted the water, and dried in the shade and in a ventle tempera- ture the red sulphurated oxide of mercury. He compared it in this state, and when very dry, with that of the Chi- nese and that of the Dutch manufactories prepared by their secret process, but did not find any sensible difference in the splendour or beauty of the red ; so that this very simple experiment puts us in possession of a process advantageous to the arts, and particularly that of painting, and which the Dutch will long keep a secret. Being 1096 On the manufacturing, on a large Scale, Being desirous to ascertain whether the air and light alone might produce a similar effect on this sulphurated oxide, M. Payssé put a hundred parts of the same substance, in powder, into a vessel of the same kind, and exposed them to the action of a strong light for more than a month. He took care, as before, to renew the surfaces very frequently by stirring the matter, in order to multiply the points of contact of the sulphurated oxide with the air which served it as an atmosphere ; but instead of acquiring a more agree- able red, it assumed a brick colour inclining to brown. After this experiment, there can be no doubt that light has a sen- ‘sible influence on this substance, and tends to reduce the sulphurated oxide of mercury by taking from it a portion of oxygen, as it does from most matters of this kind exposed to immediate contact. Red Oxide of Mercury by Nitric Acid (Red Precipitate). This oxide, so generally known in commerce by its bril- liancy and its beautiful colour, was also one of the prepara-~ tions which M. Payssé had the curiosity to see made in Holland, in order that he might learn the means employed by the manufacturers to obtain always a brilliant red of a crystalline appearance, similar to that manufactured in Ger- many, and which comes to us in particular from Nurem- ‘berg, Franconia, Bale in Swisserland, and from Trieste. Every work on chemistry gives a process for preparing this oxide; but few of them agree in regard to the means of obtaining a beautiful, lively, and brilhant red. Some, after dissolving the mercury in nitric acid, evaporate the liquor and expose the matter to a pretty violent heat for some hours, in order to decompose the nitrate of mercury and convert it into red oxide: others pour a certain quantity of nitric acid over the first solution when dried and distilled. By repeating this operation several times M. Chaptal ob- tained red precipitate very beautiful and crystallized *. Some also, after having dricd the nitrate of mercury, in- corporate with it a new quantity of fluid mercury ; and ex- pose the mixture, when well formed, to a brisk heat of a dark ted colour, between two crucibles luted together. Van Mons asserts, that in this manner he obtained, with great ease, red oxide of mercury perfectly crystallized f. All these processes, though exactly described, are not ® Elemens de Chimie, art. Mercure. + Journal de Physique et de Chimie de Van Mons; Memoires de M. Fischer et Lichtenberg, 15 Plaviose, an 10, p. 211; et 15 Brumaire, an 12, p: 178. ; ~- sufficient of some Oxides of Mercury. 197 : sufficient to the chemist who is desirous of undertaking operations on a large scale, or who wishes to apply che- mistry to the arts which depend on it. Unless one has ac- quired experience in extensive manutfactories, and been ha- bituated to the operations used in large laboratories, it will beampessible to succeed, even after many expensive and discouraging attempts. M. Payssé has often employed the different methods here spoken of, and proceeded with all the care of one desirous to succeed ; yet he never obtained results so satisfactory as he wished. He, however, adds, that the means proposed by M. Chaptal are those which were attended with the most constant success, though it was not complete. He varied his processes, employing nitric acid in différent proportions, and of a different density and purity: but, notwithstanding the quantity of crystallized oxide which he obtained, it was not possible for him to account exactly for the phenomena which occasion so many variations in the results of this operation, which js apparently nothing, and which, however, is not performed without great difh- culty. So much care ‘is required in the application of the heat necessary to be employed, that in two operations where every thing is arranged in the same manner, and where all the circumstances appear to be absolutely similar, his re- sults were almost always different. Sometimes one of the vessels contained a crystallized portion of oxide, while the other part was a red powder of a brick colour; sometimes the whole of the oxide in one of the vessels was converted into a beautiful crystalline precipitate (red oxide of mercury), and that in the riext vessel, which had been treated the same, exhibited only a mass half yellow and red, without any appearance of crystallization ; sometimes both vessels exhibited this oxide converted, in part, into a brilliant ox- ide, and the rest of a disagreeable red ; and sometimes this oxide exhibited three very distinct colours, bright red, red inclining to brown, and orange red, The second vessel exhibited only an oxide with two co- lours very distinct, orange and brick red without brillianey, «* Where (says M. Payssé) shall we seek for the cause of these anomalies but in the manner of evaporating the solu-, tion, and particularly in that of decomposing the metallic nitrate during the whole course of the Operation?’”’” We shall sce, however, that the purity of the nitric acid con- tributes also very strongly to render difficult the conversion. of the mercury into crystallized red oxide, and that the muriatic acid, with which the former is constantly mixed in - the 198 On the manufacturing, on a large Scale, the shops, presents a powerful obstacle when in too strong proportions. By dissolving mercury in nitric acid mixed with muriatié acid there is almost always formed a white precipitate, which is the more abundant as the quantity of that acid is greater. Without attempting at present to determine the real nature of this precipitate, M. Payssé considers only the part which this combined substance performs in the oxidation proposed to be given to the mercury by decomposing the nitrate of that basis by the action of heat. If crystallized nitrate of mercury, arising from a solution of that metal in nitric acid anced with muriatic acid, be exposed to heat, this salt first begins to lose its water of crystallization ; it is then decomposed, suffering to escape a portion of acid which it contained m excess, and which may be collected by means of a proper apparatus, because it has recs no alteration. This disengagement is succeeded by that of gaseous nitrous acid, which i 1s Mani- tested by very elastic red vapours. This acid gas is almost always mixed with oxide of azote, or the k: xter follows the disengagement of the former. ‘These two gases indicate the decomposition of the nitric acid, which gives a portion of its oxygen to the mercury, and is thereby brought to the nitrous state, or to that of oxide of azote. By continuing the heat, the last portions of the uitric acid abandon the mercury, and the latter is converted into an oxide more or Jess saturated with oxygen; indeed, its production seems to depend on the quantity of caloric which is accumulated on that substance during its passage to the state of red oxide. ‘ When the vapours of the nitrons gas cease, the oxidé changes its colour, passing successively from white to yel- low, from yellow to orange, and from orange to red, moré or lesa intense. It is generally wher the red is very bright and beautiful that the vessel is taken from the fire, and the mass is then preserved as it is, or reduced to powder. It would seem, on the first view, that an operation con- ducted as Bisenbks ought to give, fot constant product, at oxide well crystallized. This, indeed, is the case, Ist, When the nitric acid is free from muriatic acid, or when the latter. is in very small quantity; 2d, When its “density i is equal to 34 or 38 degrees; 3d, W hen’ the desiccation and decompo- sition of the vbcalite mitrate have been effected slowly and in an uniform manner; 4th, And when the heat employed towards the end of the operation, and while the last por- tions of the acid disunite, bas been graduated and mam- 2 tained of some Oxides of Mercury. 129 tained nearly at the same degree: for if, as many chemists are used to do, and as sometimes happened to M. Payssé, the oxide be exposed to too sudden a heat at the moment when it acquires its beautiful colour as well as its brilliancy, it loses not only its crystalline appearance, but it assumes also a disagreeable shade of reddish brown: if the heat were carried further, it would even be partially or completely de- oxygenated, and the mercury in this case would assume its primitive form, as the author, on several occasions, had an opportunity of observing. If the quantity of muriatic acid with which the nitric acid may be mixed is too great, and if it rise to several hundredth parts of the dose employed, the particular combination re- sulting from its union with the oxide of mercury assumes ° not the characters of a simple hyper-oxygenated muniate, as might at first be presumed, but that of a new compound, which dissolves only in very small quantity in water, and the latter must even be boiling; which becomes sublimed alone in close vessels, taking or rather retaining its parti- cular colour; which is brownish red, without an appearance of crystallization ; and which M. Payssé considers as a mu- riate of mercury with excess of oxide, according to the re- sults it gave when subjected to some experiments. When this compound is found in too large proportion in the oxide of mercury which has been prepared, it always opposes the formation of the crystallized red oxide, as he several times remarked in his experiments. On the other hand, if the proportion be small it may be neglected, and it even insulates itself from the rest of the oxide in the vessel . in which it is prepared: it occupies a line, and forms a se- parate stratum towards the upper part of the mercurial mass. What M. Payssé has here mentioned in regard to the advantage there is in the preparation of the red oxide of mercury by nitric acid—that an acid, as free as possible from muriatic acid, should be employed—he had remarked in the experiments which he made every year in his course of chemical lectures ; but not being able to form a very just opinion as to the results of some trials made on a small scale, and almost always uncertain, he was desirous, before he developed it, to observe with attention what takes place in the large operations performed in manufactories where considerable masses are used at onetime. Now that al] bis doubts on this subject are removed, and since he knows the phenomena which take place when several hundreds of kilogrammes of mercurial oxide are treated in one opera- Vol. 22. No. 86. July 1805. I tion, 130 On the manufacturing, on a large Scale, tion, what is the quality of the nitric acid employed, and the process to be followed in the application of heat during the whole time of the operation, the author can with cer- tainty indicate a process for obtaining this oxide provided with all the qualities required in it, and which are sought for in manufactories. Take mercury, free from every other metallic matter, 50 kilogrammes ; nitric acid, deprived as much as possible of muriatic acid*, and of from 34 to 38 degrees, 70 kilo- grammes ; dissolve the metal in the acid, and assist their reciprocal action by a gentle heat in a sand-bath+; evaporate by distillation, and take the receiver from the retort when the vapours of the nitrous gas begin to manifest themselves, as they announce the decomposition of the mercurial ni- trate. The point here is to employ a constant and mode- rate temperature, if you wish to ensure success to the ope- ration {: it is raised a little towards the end, that is to say, when the disengagement of the gaseous nitrous acid is no longer manifested, but in a manner not very sensible: the vessel must be exposed to this degree of heat till it is ob- served that the mass of red mercurial oxide is of a bright and brilliant red colour in all its parts. Eight hours of heat are in general sufficient for 200 kilogrammes of this sub- stance. * It may be tried by nitrate of silver, and if the quantity of muriatic acid appears weak itis neglected. It sometimes happens, however, and particu- larly when the nitric acid is too weak, or when the quantity is not sufficient, that the mercury is precipitated in a white oxide in proportion as it is formed, because it cannot be held in solution either by the water or by the remaining acid, and that the unoxidated mercury besides continually exercises a che- mical attraction on one of the principles of the acid, and that the latter tends rather to be decomposed than to dissolve the mercury, already saturated with oxygen to a certain degree; so that care must be taken not to confound this property with that of the muriatic acid: moreover the precipitate, which is not the effect of the oxidation of the mercury, dissolves entirely in the heated nitric acid, while the other can dissolve only in very small quantity: this property alone would be sufficient to distinguish it. I might have dispensed with making this observation, since in my process I require a very pure and highly concentrated acid ; but as it often happens that acid sufficiently strong cannot be procured,’ this deficiency may be supplied by quantity, and my remark in this case cannot be here misplaced.—Note of M7. Payssé. + This solution must be made in a glass retort, the bottom of which is broad. ‘This vessel is preferable to the matrasses employed in Holland, be- cause the only guestion here is to adapt to it a receiver, and to distil in order to collect the acid which is not decomposed on the metal. ‘This object is by no means to be neglected in operations on a large scale—Note of M. Payssé. ¢ The author wished to have been able to determine in a precise manner the degree of heat which ought to be applied to the oxide of mercury to give it the red colour as well as brilliancy; but this was impossible, because he was not provided with a pyrometer. It of some Oxides of Mercury. 131 It.has been already said that the turf employed in the manufactories of this country has some advantages over the other kinds of fuel; and this remark is true, for an equal heat may be easily and for a long time obtained, because this matter burns slowly and in a very uniform manner. As charcoal, or the coals found in the bowels of the earth, are the two combustibles employed most commonly in France, none of the circumstances here mentioned must be neglected when they are used. By strictly observing all the precautions here mdicated, one will rarely fail to obtain oxide of mercury by mitric acid | of a brilliant red colour and well crystallized. If the mercurial mass, notwithstanding all the care taken, be not brilliant, or does not exhibit the crystalline aspect required, it must be reduced to coarse powder and again put into a new earthen vessel, at the bottom of which have been placed some cubic centimetres of nitric acid only, in order that the whole of the oxide which is not brilliant may be slightly impregnated by heating it in a sand-bath. One or two hours’ exposure to heat under this apparatus will be sufficient to convert the oxide into crystallized precipitate. Resuming what has been said on the method of preparing red oxide of mercury by nitric acid, we see that the condi- tions absolutely necessary for obtaining it constantly bril- liant and crystallized are: ist, To make choice of nitric acid without mixture of muriatic acid, 2d, To employ this acid at the degree of concentration already indicated. 3d, To evaporate the metallic solution in a moderate heat. 4th, To employ a vessel, the bottom of which is suf- ficiently broad to make the oxidated mass of mercury pre- sent a great deal of surface, and that it may be equally heated with the greater ease in every point at the same time, that the nitrate may be uniformly decomposed and may pass as speedily as possible to tne state of red oxide. 5th, That the heat may be gradually increased, and in proportion as the decomposition of the nitrate advances. 6th, That this temperature may be maintained the same during the whole time of the operation, that is to say, during the passage of the yellow to the red oxide required. “¢ T am very far,”’ says M. Payssé, ‘* according to my experiments and those I have seen performed on a large scale, from believing that crystallized red oxide of nercury is indebted for this brilliant appearance to a state of semi- L2 vitrification, 132 On the manufacturing, on a large Scale, vitrification, as M. Van Mons thinks*; for it would fol= low, if this oxide were really half vitrified by this ope- ration, that a higher temperature would be capable and ought necessarily to convert it into glass: but nothing of the kind takes place; for I have exposed to a very strong’ heat, and at several times, four grammes of this oxide, well crystallized, in two crucibles luted together, and, instead of vitrifying, it lost not only its brilliancy but also its fine red colour, and acquired one of a disagreeable brick red. Ex- posing it toa still greater heat, a great part of it was reduced, and the rest of the oxide acquired a dark brown colour. “© T know, however, that there are bodies which are not susceptible of passing to complete vitrification, and which. nevertheless experience, at a certain degree of heat, a paste- like fusion which is called semi-vitriform ; but by heating the oxide of mercury in transparent vessels nothing similar is seen to take place, not the least vestige of a partial or general softening of the mass is observed. Besides, I have strong reasons for believing that the crystalline state of the mercury oxidated by nitric acid arises only from: the degree of the oxygenation of that metal, and the uniform manner in which the oxidating principle combines with the mer- cury during the decomposition of the nitrate of that bases. and its conyersion into red oxide.” XX. Second Extract from a Memoir of M. Paysse, prin- cipal Preparer of Medicines at the Camp of Utrecht, on the Method of manufacturing, on a large Scale, some Oxides of Mercury. By M. ParMENTIER f. Diercrve remains, in order to make known the memoir of M. Payssé on the oxides of mercury, but to give a short view of the other experiments he made in regard to the red’ oxide of mercury by nitric acid (red. precipitate): they form the complement of his process given in the preceding ar- ticle. Ifthis process be followed, it will remove all the un- certainty of manufacturers who hitherto have not been able to prepare this substance as is done in Holland. Every thing is easy in theory; but in the arts facts speak much: better than the most brilliant reasoning. ‘Fo ascertain that the crystalline state of the red oxide of * Journal de Physique et de Chimie, années 10 et 12, pages 178 et 211. + From the Journal de Chimie, No. 154. ' “mercury of some Oxides of Mercury. 133 mercury does not arise from a semi-vitrification, as M. Van Mons asserts, M. Payssé made a solution of mercury in nitric acid mixed with some hundredths of muriatic acid, Having evaporated the solution to dryness, he treated this matter with the same care and caution as the former; and when the operation was finished the mercurial oxide exhi- bited a red aspect, sufficiently beautiful in some parts and dull in others, but without any appearance of brilliancy or erystallization, This mass was pulverized, and again in- troduced into another glass vessel, into the bottom of which he took the precaution of pouring a small quantity of nitric acid, that the mercurial powder might be slightly impreg- nated. He then proceeded as before, exposing the vessel . to a gentle and graduated heat. But, notwithstanding all the precautions he observed during the operation, the oxide which was the result of them had passed to red without exhibiting the least vestige of crystallization or brilhancy. This experiment was repeated three times, but with no better success. It is evident, however, that if the red oxide of mercury is indebted for its brilliancy only to the semi- vitrified state it experiences when heated, there is no reason why this matter should not be constantly in the same state every time it is prepared, since nothing is necessary, ac- cording to Van Mons, but to apply to it a violent heat be- tween two crucibles luted together. In preparing crystallized red oxide of mercury, M. Payssé made observations which gave him reason to suspect that the brilliant state of this substance is owing rather to the constant degree of the oxygenation in which the mercury is, than to any other cause, and that the presence of the muriatic acid in the nitric acid is an obstacle to the forma- tion of that brilliant state by the new combinations to which it gives birth during the operation. What he supposed is now become certainty, as the following experiments will show. He took a hundred parts of red oxide of mercury, brilliant, and prepared by nitric acid mixed with muriatic acid ; and, having introduced them into a long-necked matrass fur- nished with a bent glass tube communicating with a pneu- matic apparatus, they were gradually heated till the bottom of the vessel became red. He suffered to escape the whole of the atmospheric,air contained in the apparatus, that he might obtain, free from mixture, the oxygen gas furnished by the oxide. Having exposed the matrass to heat for a sufficient time, and waited for the complete reduction of I3 the 134 On the manufacturing some Oxides of Mercury. the mercurial oxide, he suffered the whole to cool, and diluted it. He then decanted the mercury, and collected the whole which adhered to the neck of the matrass: its total weight was 0°81. The receiver which had served to collect the oxygen gas was obscure, and indicated that a small quantity of mercury taken trom the gaseous state was con~- densed on its interior sides. To force the oxygen gas to abandon all the metallic particles which it might contain, he surrounded the receiver with pounded ice; and when the receiver had cooled for an hour he conveyed the gas into another vessel, and collected with care the whole of the mer- curial oxide which lined the inside of the vessel. Slight friction with the finger against the glass was sufficient to effect the reduction of it, and to collect it in globules in a brilliant state. Its weight was 0:02, which with the 0°81 found in the matrass gave 0°83. The neck of the latter vessel exhibited small white crystals, which he collected with care: their weight amounted to about 0°01 ; and their taste and other chemical properties convinced him that they were hyper-oxygenated muriate of mercury. A reddish powder inclining to brown lined also a part of the dome of the matrass, which it was necessary to break before it could be collected. When carefully examined he found in it the characters and properties of this new combination, already mentioned in the beginning of this memoir, and which he calls muriate of mercury with excess of oxide: its weight was 0°03. By these results it is seen that the quantity of oxygen was 0°13. The same experiments being repeated several times in succession, the results were always the same as the preceding. A hundred parts of red oxide of mercury, very brilliant and well crystallized, and prepared with nitric acid free from muriatic acid, were treated in the same manner as in the preceding experiments: the reduction of the oxide was complete, and the products were exactly 0°82 of mercury and 0°18 of oxygen. M. Payssé treated in the same manner red oxides of mer- -cury prepared in the Dutch manufactories and those he ob- tained by his own trials: the proportions of the principles which constituted these oxides, all very brilliant, exhibited variations very little sensible. They amounted only to nearly a hundredth part; so that it may be considered as certain that crystallized red oxides of mercury are indebted for this state to a combination of oxygen with the mercury, the proportions of the former being always between 18 and _ while On a nondescript Aquatic Animal. 135 while those of the oxides which have not brilliancy contain at most from 13 to 14 of that principle. Two incontestable advantages result, then, from the pre- paration of crystallized red oxide of mercury. ist, An increase of the product of that oxide, the mean term of which is five per cent. more than when it is not brilliant. p ‘2d, The impossibility or at least great difficulty which avarice may experience in adulterating this product of art by red oxide of lead. XXI. Facts relative to a nondescript Aquatic Animal. By Mr. Joun Snart, Optician. To Mr. Tilloch. . SIR, Hoasewien I send you the exact drawing of a very sin-: gular aquatic creature 1 have lately discovered residing in ponds in which the frog, &c. is generated from the first rudiments or spawn of the parent and brought forth in the tadpole state; in which stage of being it becomes the prey of the said creature; without the persecution of which, I am persuaded frogs would infinitely more abound than at present. The creature in question is of a most curious construc- tion; having six legs, with the feet armed with talons, two palpi or feelers, and four antenne with a bifurcated plu- mated tail. The body is divided into ten semi-crustaceous lobes somewhat Jike-the armadillo (exclusive of the head and neck, which form two more), by means of the joints of which he is enabled to inflect himself into almost any posture. The head is flatted like the scollop, and broad; the mouth is of the whole width of the head; and proceeding from the sides of the superior mandible or upper jaw spring two ten- tacula-like forceps, which it opens or closes at pleasure ; these are curved and pointed like those of the forficula or common earwig, and with these it seizes its prey, of which the tadpole seems to be the principal favourite. Though tadpoles are frequently found much larger than it, yet it pursues them with the greatest confidence. When it over- ‘takes them it punctures their skin with its forceps, and, after lacerating them so as to fetch blood, drags them towards its mouth, into which it receives the effusion. 14 So 136 On a nondescript Aquatic Animal. So insatiably voracious is this little water dragon (if I may use an appropriate epithet for want of a name), that in the space of a few hours (and that in the night), out of about eighteen, it had killed, and withal much maimed, no less than eight or ten tadpoles, most of which were bigger than itself; aud could it have made the same rapid progress in the water which tadpoles do, I have no doubt they would all have fallen a sacrifice ie this little sanguinary tyrant, who (with short intervals of rest after a full meal) is inces+ santly roving in search of blood! At first sight it appeared to be of the binocular class; but taking a good magnifier, I observed the eyes to be com- posed. of two annular clusters, not reticulated, but each containing six distinct, roundish, bright, lack orbs, at small distances from each other; the Tntermediate spaces, as well as more considerable ones, in the centre of each cluster, being of a piece with the colour and texture of the skin of the other parts of the body, which, with some little variegated exceptions on the back of the head, is of a co- Jour resembling the mud of the Thames water, of the tex- ture of that of a common shrimp, and like it (when alive) of a semi-transparent nature. Indeed the divisions of the whole body are more like this than any other creature I have yet seen. But its conformation in all other respects is quite as dissimilar as I have stated. When it seizes its prey, if exceedingly. vulnerable like the tadpole, it lacerates it so deep as to make the forceps mect and even cross in the punctures, when it amuses and gratifies itself by working them in and out until the blood flows from the wounds, ‘at which time they are alternately withdrawn and applied to the mouth, as if to taste the gore with the one, while the captive is detained by the other ; which if it approves, the poor struggling victim is drawn there too; but if otherwise, it contents itself by repeated lacerations until its imaginary enemy is dead, as was the case with a common earth-worm I threw into the water, atid ‘several flies, which were never drawn towards the mouth at all; while the tadpoles are exhausted of their blood until they become a mere skin with a small propor- tion of gelatinous matter left in it; for their adversary seems not to have convenient organs for entire deglutition, or he would no doubt quickly destroy the whole subject: but owing to the narrowness of the neck, and its crustaceous texture, the cesophagus is incapable of expansion to any considerable degree; yet this incapacity on his part is no 6 - security On a nondescript Aquatic Animal. 137 security to the other, seeing they are almost cut in two by their being brought into so close contact with the mouth of their destroyer, and quite drained of their very vitals. Thus nature, as if to counteract her wonted profuse fe- cundity in this diminutive scale of beings on the one hand, seems om the other to have made this formidable nonde- script adversary to thin the race. So tenacious is he of his prey, that, having once fastened on, he will bear to be drawn quite out of the water, and held for some minutes suspended by the hold he has taken by the forceps ere he will let go his victim ; and so determinately undaunted as to bear to be lashed with a small twig, which he has the hardiness to endure. The opening of his forcéps scems to fascinate his victims; they become, as it were, transfixed by torpor, and riveted to the spot, though naturally capable of swimming much faster than their enemy. One particular more which I observed may not be amiss to notice, which is, the ebbing and flowing of the blood, which does not appear to circulate through ail the parts, but by a kind of undulatory motion, or rather pulsation, pro- ceeds and recedes towards and from the head to about half way down the body in one entire mass. Though without doubt the whole frame is visited by this vital principle, yet it is in such small quantities as to elude the most minute inspection I could bestow upon it; and if the quantities were not, indeed, very minute, it could not but be visible through the semi-transparency of the body; for it is not limpid hike water, but of so sanguine a tint as to give the middle part of the body a black appearance. Notwithstanding these minute particulars which I have made myself acquainted with, I shall not venture to deter- mine what class it ranks in, because it seems to participate of several, or at least to possess members and faculties in common with two or three; and as I could not gain any information on thishead from my books, thouch there seems somewhat very characteristic in this creature, I thought it might not be impertinent or displeasing to some of your read- ers to have the best information I could extract trom strict observation of its functions and amusements, And although it comes without the minuteness and accuracy of zoological classification, yet I believe I am perfectly correct in every particular stated, in which if I meet your concurrence it is very much at the service of your readers. Description of the Drawing. (See Plate II.) Fig. 1. View of the back parts, magnified, Fig. 138 On Elasticity. Fig. 2. The animal of its natural size, the belly upwards. Fig. 3. Under part of the head as seen in a strong light, by means of which not only the outward but also the in- ward direction of its members is discernible: thus we see the roots of the antennz join together and communicate — with the two great canals @a, which carry the blood to all the parts; and I am persuaded the forceps join issue there too; but the parts are too glandular to allow of this being distinctly seen. ; Besides, upon the creature eating some mackrel liver, a great quantity of blood was discharged from the under fis- sures near the tips of these forceps a great number of times. Meeting with a medium of nearly the same density as it- self (2. e. the water), it diffuses itself in the form of a thick smoke issuing from -a furnace chimney when fresh fuel is added; after which the forceps became so close that no magnifier I could use upon him would enable me to see them: yet this affords a presumption that they are each a kind of proboscis. Some blood was discharged from the mouth at the same time. Fig. 4, The eye of its natural size. Fig. 5. The same magnified. London, 215, Tooley-street, 20th June 1805. XXII. On Elasticity. By ALEXANDER TILLocH. An Essay read lefore the Askesian Society in the Session 1802-3. I; is not my intention in the present paper to enter upon any inquiry respecting the laws by which elasticity acts, as they have often been investigated already, and are well known to every one acquainted with the first elements of mechanics. I mean merely to confine myself to a few thoughts on the physical cause of elasticity, or that pro- perty of bodies which enables them, after any external pres- sure, to restore themselves to their former figure. The cause of elasticity has been proposed to be accounted for in various ways. The Cartesians held that it was a ne- cessary consequence of their materia subtilis, or matter of the second element, making an effort to pass through pores too narrow for it. Thus, when a straight elastic body is bent by any force, the pores become contracted on the con- cave side, and, if they were before spherical, become for instance elliptical, or of some other form; and the materia subtilis, ES Re “ f Bh * : On Elasticity. 139 subtilis, hindered in its attempt to pass, makes an effort to restore the body to its first state. In this theory there is something like the effort of a strong mind when first seizing upon a new truth, and endeavouring to reduce it to a de- pendence on and connection with known or admitted facts; but the defects in the reasoning ought to have convinced its supporters, that a more satisfactory way of accounting for the phenomenon was still a desideratum. It must be obvious to any person who will take the trouble to ana- lyse the argument, that if the materia subtilis in a spherical cavity could by pressure (being hindered at the same time from passing off) accommodate itself to the same cavity rendered elliptical, that in doing so it has in fact become smaller in volume than it was before. The materia subtilis is thus assumed to be compressible; and, as it makes an effort to restore the body, or, in other words, its cavities, to the first form, it is assumed to be expansive. But what does this amount to? Merely that. a body is elastic because it contains elastic matter. Other philosophers, disliking the materia subtilis of the Cartesians, have adopted an ethereal medium. Their mode cf reasoning, however, is so similar to that of the former, that they leave the mind as unsatisfied as before. Indeed, the mere change of a name can throw no new light upon the subject. Some account for elasticity by supposing that when an elastic body is bent or compressed a number of little vacui- ties are formed in it, and that on removing the force the pressure of the atmosphere, endeavouring to destroy the vacuities thus formed, restores the body to its first figure. This doctrine, however plausible, is inadmissible, if for no other, for this one reason:—Many bodies require a greater force to bend them to any given degree than can be found by multiplying the number of square inches in their surface by 14 pounds, the force exerted by the atmosphere on a “square inch; besides, the phenomena of clasticity manifest themselves in vacuo. Others assume that all bodies contain air in their vacui- ties, and ascribe their elastic property to that of the air in- closed in them. This is little more than a substitution of air for the materia subtilis, and the ether assumed by others. But whence has air itself the property of elasticity? This is a part of the general inquiry, and as necessary to be solved as the source whence other bodies derive the same property. thers account for elasticity from the Jaw of attraction, applied 140 On Elasticity. applied with so much success, since the time of Newton, to the solution of many other of the phenomena of nature 5 and we are inclined to think that the more this subject is investigated the more will it appear that it acts an important part in producing those effects ascribed to elasticity. Ac- cording to this theory, when an elastic body is struck or bent so that the component parts, or portions of them, are moved a little from each other, but not beyond their spheres of attraction, they must, on the cessation of the applied force, spring back to their natural state. _ Repulsion also has been held to be the cause of elasticity in the case of aériform fluids, and this repulsion is ascribed to the presence of heat. In this case repulsion is not made » use of as the last term of our knowledge, but merely as expressive of a certain state of action ascribed to another cause. Some, however, make use of the expression with- out so defining it, and, if they mean any thing at all, use it to express an abstract property of which they know not the cause. We may therefore obscrve, in passing, that this term should be used as scldom as possible in philoso- phical subjects, and never unless the author has defined the sense in which he employs it. Another theory has been proposed, which has been ad- mitted by many as sufficient to account for all the pheno- mena, not of the elasticity of bodies only, but of matter in general. This theory, which has the celebrated Boscovich for its author, supposes that the whole matter of the unt- verse consists of a great but finite number of simple, indi- visible, INEXTENDED atoms, endued with repulsive and at- tractive forces, which vary and change from the one to the other according to circumstances pointed out in his System of Natural Philosophy, of which a good account may be seen im the Supplement to the Encyclopedia Britannica, under Boscovich. The most singular part of the system is, that his atoms, in their least and innermost distances, repel each other, and this power of repulsion increases as the distances are diminished: in sensible distances they attract each other, and this power decreases as the squares of the distances in- crease, constituting universal gravity: between the inner- most repulsive force and the outermost attractive one, in the insensible distances, many varieties occur; at a certain distance the repulsive force vanishes—increase that distance, and attraction begins, increases, lessens, and vanishes, till, at a certain increase of distance, the force becomes repul- sive; and so on alternatciy, always changing from the one to the other with the increased distances ; sometimes more slowly, On Elasticity. 141 slowly, sometimes more rapidly, and sometimes one of the forces may come to nothing and then return back to the same kind without passing to the other. And for all this, it seems, there is full room in the distances that are IN- SENSIBLE fo us, seeing the least part of space is divisible in infinitum. Assuming all this, and exhibiting a curve and other ne- cessary appendages to assist the mind in comprehending his theory, the author applies it to explain all the phenomena of the material universe, assuming also in his progress such forms and arrangements as are required to make the system apply to the properties possessed by matter in those modi- fications which distinguish and divide it into classes: thus solid bodies are formed of parallelopipides, fibres, and of ir- regular figures, occasioning a greater cohesion haart in fluids, and pteventing the motion of the parts round one another ; so that when one part is moved the rest follow. Those bodies whose particles are placed in limits which have strong repulsive arches within them are harder; those are softer whose particles have those arches of repulsion weaker. When the particles are placed in limits that have weak arches of repulsion and attraction on each side, the body is flexible; and, if those arches are short, the particles may come to new limits of cohesion, and remain bent: but if the arches are longer the repulsion and attraction may act, and restore the body to its former position; nay, in doing this with an accelerated velocity, the parts will pass their former limits, and then vibrating backwards and forwards exhibit that effect which is called elasticity. On this theory we shall only observe, that whatever con- yiction it may carry to minds habituated to profound ma- thematical investigations, it can convey but little informa- tion to a man who merely aims at a knowledge of the pro- perties of matter, as consisting, not of inextended atows, but of such molecule as occupy ‘sensible space. What the wiser is such a man for being told that certain forces exist, and that some idea may be formed of their mode of ope- rating by conceiving them to act in the directions of certain curves, and with powers varying according to circumstances? He may assent to this; but as 3 his weak Tind can conceive nothing of matter inextended, either in itself or in its atoms, he cannot consider his difficulties as solved bv merely hav- ing them stated to him in a new form; for to him the whole of this system appears to be no more at best but a regular mathematical statement of those operations of matter, the causes of which he still wishes to explore. C. Barruel 142 On Elasticity. C. Barruel has proposed a theory different in some re- spects from any of those [ have mentioned,—more in ap- pearance, however, than in reality. He contends that ca- loric acts a great share in the phenomena of elasticity, and maintains that i¢ is itself elastic in consequence of the pro- perty which the moleculz of this fluid have of repelling each other: a property, he says, the more probable as it 1s ob- ¢erved in the electric fluid, with which caloric has so great an analogy. * In a word,”’ says Barruel, ‘* we may be satisfied with admitting its elasticity as a fact from which we may set out as from an incontestable principle.” To enter at great length into this theory, an account of which may be seen in the sixth volume of the Philosophical Ma- gazine, p. 52, would encroach too much on or present time. The author presents, in his memoir on this subject, some curious thoughts, and well worthy of a perusal. It is only necessary here, however, to state in few words the substance of his reasoning. Ist, Every body in nature is porous, and these pores are proportioned to the density of the substance: 2d, These pores are filled with different fluids, and principally with caloric. But caloric possesses a strong repulsive force; from which it follows, that, when an elastic body is compressed, the caloric in its pores drives back, by its repulsive power, the displaced parts, and brings them to their former state. On this theory it may be observed, that however true it may be that caloric acts a distinguishing part in the phe- nomena of elasticity, the author seems to have made hardly any other use of the fact than to put that substance in the place of the materia subtilis and ether of the earlier philo- sophers. He assumes too that it necessarily possesses elas- ticity; but he ought either to have first proved it, or at least to have demonstrated, that if that property be not in- herent in caloric, there could be no elasticity in other mat- ter. In short, were it even proved that caloric is naturally and essentially elastic, and the cause of elasticity in other matter, still the main question would remain unsolved, which would then be—What is the physical cause of elas- ticity in caloric? Libes makes elasticity to depend on caloric interposed either between the molecule of bodies or combined with them, and at the same time on the attractive force of these molecule. ‘ This being premised,” says he, “ I say that the restoration of solid bodies after compression is a com- bined effect, which depends in part on the repulsive force which their integral molecule haye received sil ca- oric, On Elasticity. 143 Joric, and in part from the attractive force of these mo- leculz.” I should have been glad to have been able to have given something more of Talsckts theory than this short notice, especially as this little seems to approach nearer to my ideas of the true theory than any thing I have yet noticed; but I know not in what work it is given. This notice is from the Journal de Physique, vol. |. p. 10. an 8. Thus have I given a short account of all the theories that have been advanced to account for the phenomena of elas- ticity; or, at least, of all [ recollect worthy of notice. Some of them, we have seen, in passing, fall entirely short of the object they aim at, and are therefore unworthy of further notice. In others, however, the mode of argument is so well managed, that had their authors attended to a single fact or two, which they have overlooked, it is probable that the subject would, before this time, have received that fall elucidation of which I believe it is capable. . Like those who have gone before me, I may fail in the task I have imposed upon myself; but I hope to avoid in- consistency or unfair assumptions. It does not appear neces- sary to admit cven that elasticity belongs to matter consi- dered simply. Indeed, I think the contrary is the fact. But that my meaning may not be mistaken, I shall explain in as few words as possible this part, which may be considered as fundamental, of the doctrine I mean to propose. By simple matter I mean the primitive molecule, or atoms, of which bodies are formed. However complex may be the state in which we find bodies, they consist of elementary principles, which principles themselves are formed perhaps of others, but ultimately of imelastic atoms of simple mat- ter. Let us, for example, take some matter considered as simple and elementary, say caloric, J would affirm of it that it is not necessarily elastic; and so of any other simple matter. But if elasticity be not essentially necessary to matter considered simply, whence do bodies derive that property ? I answer, From the saine source-whence they derive almost every other quality that belongs to them—from their com- position and internal arrangement. I would have said aut their qualities, instead of limiting the expression to almost all of them, but that they possess one property which may, and probably does, depend on some other cause, I mean that of attraction. Of the cause of this we know nothing; but its existence and the laws by which it acts being known, philosophers do not fail to avail : themselves 144 On Elasticity. themselves of them in explaining those phenomena into which they enter. In our present inquiry, then, I mean to derive from at- traction the help it offers in explaining the cause of elasti- city; and I hope to make it evident, by a due considera- tion of attraction as common to all matter, and of th¢ laws by which caloric constantly endeavours to maintain an equi- librium, not only among systems of bodies, but throughout each individual mass, that the efforts of these two, to main- tain their respective powers over matter, and, in doing so, acting according to known and invariable laws, produce all those | phznomena to which the term elastic has been applied, whether in solid or in-aériform substances. , I would say, then, that attraction, which pervades all mat- ter, and caloric, which also pervades all matter, by their pre- sence, and by an action in which both participate, occasion elasticity wherever it exists. Not that elasticity must follow as a necessary consequence of their presence, for then every substance in nature would be elastic, which many are not in the common sense of the word. Certain other conditions are necessary to elasticity; but without these two it could not exist. It is admitted by all that attraction is the cause of the aggregation of the molecule of bodies. When the state of agsregation is such, that on the application of a given degree of mechanical force to the body the attraction of the mole= culz is overcome (or the body broken), it is called brittle: if the attraction is only partially deranged, the body will be found to have changed its form, and is then called flexible: when the body springs back, or, after certain vibrations, recovers its form, it is called laste! Many metallic bodies which are ficxible in the sense just mentioned, may however by hammering be rendered elastic; that is, by ‘merely bringing their molecule into more inti= mate union, or by bringing them reciprocally more within the spheres of cach other’s attraction. This is a circum- stance which ought not to be lost sight of. Let us fora moment then inquire what takes place in the process, be- sides bringing the particles of the body more nearly into contact, or more of them into actual contact than were in that state before?) When a bar of metal is hammered thin- ner than it was before, a quantity of caloric equal in volume to the diminution of volume imposed upon the bar has been expelled or driven out of it. I need not, however, insist on its being exactly equal in volume, as my present argu- ment only r requires that a certain quantity of caloric should be On Elasticity. 145 be driven out of the mass by the operation; and I believe in the present state of our knowledge that few will be in- clined to dispute it. As it is, however, of some importance to establish this point, I shall, before proceeding further with the main argument, briefly point out some of the cir- cumstances which seem to prove the escape of caloric: The bar becomes heated by the operation, and where heat ma- nifests itself, it must be ejther passing off from or into the body. If the capacity of the body be diminished at the same time, and the chemical properties of the body remain unaltered, which in the instance under consideration is the case, how can we mistake the direction in which the caloric moves ? I am aware of what has been advanced respecting friction by men whose names stand high in the philosophical world, and that hammering is a species of friction: buat names and opinions should never be substituted for facts; for, if it be true, which I deny not, but maintain that hammering is a species of friction, it would not be difficult to show that it is equally true that friction is a species of hammering. But if by hammering such a quantity of heat may be driven from the interior to the surtace of a bar as will produce effects similar to those of a combustible body in a state of ignition, the caloric in this as in every other case must be something else than mere motion. It is subject to certain laws of motion, like every other species of matter ; and like every other species of matter too, when moved from its place by any force, putting other matter in the space or spaces before occupied by it, it must take up another resi- dence. To produce an accumulation of heat by hammer- ing, repeated and a long continued succession of strokes are not necessary: proportion the mass oi metal to the im- pulse to be applied, and with one stroke you may produce such a heat as will make the part of the metal where it is accumulated visible in the dark—hot enough to set fire to a combustible body. It may here be also observed that heat is propagated even through what is usually called a vacuum, that is, through spaces absolutely void of every other species of matter, which could not possibly take place if caloric were not sub- stantial ; for motion is a non-entity when we attempt to con- _ceive of it as distinct from matter—it is an accident of mat- ter, and when we speak of its existence the presence of matter is always Merhels This is an argument in proof of the substantiality of caloric which no powers of argument can overturn ; for, whatever semblance of truth may attach Vol, 22. No. 86. July 1805, Kons to 146 On Elasticity. - ne to reasonings on motion as connected with matter, it vae nishes entirely when the continuity of matter is broken, as in the case we have stated. But if int he case of the trans- mission of caloric through a vacuum, caloric is proved to exist independently of motion, why in any other ease should the two be confounded ? But to return—A bar of metal by being hammered has a quantity of caloric expressed from it by 1 mere mechanical means, without undergoing any chemical change. In other w ords, its capacity for holding caloric has been abridged, without its afinity for that substance being lessened ; ‘and the aggregation of the mass has been increased i in a ratio bearing some proportion to the diminution of its capacity for caloric: ; When the hammer is first applied to the metal, the latter is, comparatively speaking, plastic, and gives but little re- sistance ; but as the parts are brought into a closer state of aggregation the resistance increases, and the hammer recoils in proportion to the force with which it is applied and the degree of aggregation the mass has acquired: in other words, the metal has acquired a degree cf elasticity propor~ tioned to the time it has been subjected to the mechanical process. It appears then that by diminishing the capacity of the metal for heat, while its natural affinity remains un- altered, it acquires the property of being elastic. Let us attend a hittle to the case before us. When the metal has received a certain degree of compression from the hammer, it refuses to receive more, and the hammer recoils; that is, by mechanical means a certain degree of caloric may be expressed from the metal, but as its affinity for caloric cannot be destroyed, the last portions of it cannot be ex- pelled by any such process; and even a portion of what “may be expelled can only be momentarily separated, viz. only during the continuance of the impulse. It is this last circumstance that occasions in the instance under examina- tion an exhibition of what is called elasticity. That I may be the better enabled to convey my ideas on this point, I shall here call in the assistance of a figure to illustrate my meaning. Let ABCD (Plate Tl. fig. 6.) be a mass of metal that has received all the density of which it is susceptible by hammering, or let it be a mass (as an anvil) hardened by any other process,- in such a manner that it can recetve no more permanent compression from the action of a hammer. If a stroke of a.hammer be applied on the surface ABC, a momentary depression of the surface will take place, pro- portioned On Elasticity. ‘ah portioned to the force that has been.applied. Say that the curved line AaC represents this depression, and the area ABCa its quantity: a quantity of caloric equal to the space ABCa is momentarily displaced by the blow, But in this case an attempt.is made to separate, by me- chanical means, a portion of that caloric which the mass demands by its affinity; and this law, exerting itself to re- store the equilibrium, takes back the quantity thus violently attempted to be taken away, and with such rapidity that the hammer is no sooner at @ than it is instantly pushed out by the reimbibed caloric. Nor is this all: caloric, being matter, must, when put in motion, obey the same laws that:other matter would in similar circumstances. The re- seryoir that furnishes the supply (viz. the surrounding at- mosphere) being inexhaustible, instead of the caloric ceasing to operate when it has brought the surface again to coincide with ABC, it carries it to ly a distance as far above B, or nearly so, as a was below it; and it is not till after repeated vibrations between these points that thesurface at last comes to rest in its first position. Any one may satisfy himself of this fact by letting a hammer fall upon an anyil while he holds the handie easily in his hand; it will not give one. but several strokes, proportioned to the force employed. When the recoil of the stroke, as it is called, has carried the surface to l, why does not. the mass retain the caloric (represented by the space ACB) which it has received by the effort thus made by its affinity for caloric ?—Because the affinity of aggregation of the mass forbids it. The twovaf- finities—that of the whole mass for caloric, and tlrat of the moleculz for each other—find their powers balanced when the surface comes to rest in the line ABC. From what has been stated respecting the effect produced by the blow of a hammer on a hardened mass of metal, it will not be difficult to trace the effect that will follow if a soft bar of metal be interposed. We have seen that a quan- tity of caloric is momentarily expelled from a hardened mass of metal when struck by a hammer, and as quickly reimbibed with an increase of quantity. When such a bar is 8truck on an anvil with a hammer, there is a displacement of the caloric ftom the part struck; and at the same time an in- ¢rease in the aggregation of the molecule in the same part, that is, an increase of its elasticity. The quick retum of | caloric into the part makes the hammer recoil; but the mo- leculze having been brought closer together by ihe blow, the caloric finds less lodging-room than before, and of course an iperease of temperature follows; for the affinity of the K 2 masg 148 On Elasticity. mass for caloric is lessened as its molecule are brought. closer together. A second blow is followed by a like effect, which is in like manner increased by succeeding blows. It is necessary, however, that these be given in such quick succession that the bar may not have time between to give off its caloric to surrounding bodies. If this be attended to, an accumulation of caloric must take place in the bar ; for by the second blow a larger quantity of heat is displaced than by the first, and consequently a larger quantity 1s im- bibed to be affected by the third blow; the quantity dis- placed by each blow being proportioned to that which was before present, and the quantity newly imbibed being pro- portioned to what was displaced by the last blow. This fact, with some latitude, will always be found to hold true. Need we wonder then at seeing a dexterous artisan lighting his forge without any other heat than what he can furnish to himself by means of his hammer and an iron rod ? In the case which we have just examined the phenome- non appears to depend on the displacement of caloric in a body by an external force, while the affinity of aggregation endeavours to retain it. Will this be found to hold in other eases ?—Yes, making allowance for the difference of cir- cumstances, Let AB (fig. 7.) represent a spring of steel or any other metal. By any external force let it be bent into the form CD. It is plain that one side of the spring has been elon- gated and the other shortened. But the spring before flexure had its moleculz respec- tively at those distances or in that arrangement in which they best balanced each other ; that is, the mutual effort of all was to keep the spring in the state it exhibited before any external force was apphted ; and the quantity of caloric resident in the mass was distributed throughout in propor- tion to the affinity of all the parts. Let the proportion of caioric proper to any part of the mass in any common temperature be represented by the space comprehended between the two parallel lines ad and | ed. When the bar is bent, the lines al and ed are made to approach each other, as at e on the concave side, and to re- cede on the convex side, suppose to f and g, so that they no longer remain parallel. In other words, a quantity of caloric has been displaced from the one side, and has found lodging-room in the other side of the bar; and what is said of this is understood of every other part of the spring. But the affinity of all the parts for caloric haying undergone no ; \ ; change, On Elasticity. 149 ‘change, it is plain that when the external force is removed it must resume its first position in the mass, and, by doing SO, restore it to its former figure, in effecting which the af- finity of aggregation co-operates; for we, have been sup- posing such a force only applied as could change the form, while applied, without overcoming the aggregation of the mass. The vibrations which follow, if the spring be left quite free after force has been applied, may be explained in a way perfectly similar to what we have already laid down when speaking of a bar struck by a hammer. The caloric being put in motion, a larger quantity of it runs from the plus side to the side that was minus than the afhinity of the latter demands, and is therefore driven back again, and so alter- nately, till by httle and little it ceases its motion as equili- brium comes to be established. After the bar AB has by any applied force been brought into the form CD, the caloric, which in the natural state of the bar resided between J and d, having been forced to find lodging-room towards ac on the side now rendered convex, and the lines ab and cd, or the portions of metal which they represent, being brought into contact in the point e; or, if the possibility of the perfect contact of the moleculz be denied, as nearly into contact as possible in the point ¢; then the said point e (and so of any other point of the concave surface) becomes a fulcrum over which: the bar may be broken if an increased force be appiied ; for all the caloric that can be removed by mechanical means from the concave side having been transferred to some more convex part of the bar, it must follow, as a consequence, that any attempt to make the metallic matter enter spaces already occupied by metallic matter must be vain, and can only operate to draw the molecule on the convex side to such a distance from each other as to adinit foreign matter between them, viz. the atmosphere or other surrounding medium, after which it will be impossible for them to coa- lesce again. ; In this way would we account for that effect which has hitherto been ascribed to the molecule being remaved to such a distance from each other as to place them beyoud each others sphere of attraction. It is true they are brought into such a situation that their attractive affinity cannot again unite them as an ageregate ; but we think their attrac- tion is not annibilated, as the common mode of expression may suggest to those who do not properly examine the matter, There is only a new affinity brought into play, K 3 Vi 130 \ On Elasticity. viz. that of the metallic molecule for the newly interposed body ; for, could that new affinity be destroyed, or, in other words, could the interposed substance be entirely removed, it is probable the atlinity of the molecule would again be exerted. Of this some idea may be formed by attending to what takes place when two spheres’of lead, a little flattened, are pressed together. In propertion.as the air has been ex- cluded will be the adherence of the two balls. We would not wish, however, to be understood to/assert that in every case a-disjoined mass would unite but for the newly interposed substance, for several conditions are re- quisite to this eflect which can rarely exist. Among these may be mentioned, that there should be no new arrange- ment of portions of the broken surfaces by the metal having by its tenacity drawn itself out into fibrous ligaments and protrusions; for in that case the points of contact upon joining the masses are so limited that the very weight of - either part, that is, its gravity for the common centre of attraction, will act as a sufficient force to destroy the affinity which exerts itself to keep them united. We may also here remark, that in the confused crystallization of melted masses of metal, some of the portions may always be conceived to be under some restraint, as it were, and this must hold also after the metal has been hammered. Therefore on breaking the mass some of these will always protrude, or in some ’ way or other change their position a little, so as to produce an effect similar to that before described—reducing to a comparatively small number the points that can be brought into contact. Therefore what we mean to suggest is only this—that if every interposed substance could be entirely. ‘removed, and it were possible to bring the original number of points into. contact, the affinity of aggregation would act to unite the parts of the mass. I might apply the reasoning employed in the case of the spring AB to other cases of solid bodies; but, from what I have said, I think any person may apply my reasoning in the same way as I would myself, whether he be convinced of its truth or not; to enlarge further appears therefore un- necessary. Jt is proper, however, that I should endeavour to show how the same doctrine applies to aériform fluids. When air is compressed, on removing the force it regains its first volume. This, however, is conditional. If the compressed air be of a given temperature, say 80°, and if it be afterwards reduced to a lower temperature, say 32°, it may so happen that the diminution of volume by reduction of temperature may more than counterbalance the com- pressing On Elasticity. 151 pressing force that was employed. In this case, then, a mere abstraction of caloric annihilates a certain quantity of elastic force which belongs to the air when the common temperature is higher. » Again: Inclose a given quantity of air, not compressed, in any proper vessel, when the common temperature is 30°, and it will be found when the temperature becomes high, say 80°, that it has acquired an elastic force which it had not before. The cause is obyious. The air inclosed.at 30° has as strong an affinity for caloric when the common temperatur comes to 80° as the air not inclosed, but is prevented by want of room from satisfying itself to the extent_of its afh- nity. © On opening the vessel, however, the caloric finds an easy admission; the volume of the mass becomes increased, and a quantity equal to this increase disvharges itself. But when by force we compress air which is to be again liberated without waiting tor any remarkable change of tem- perature, we only accomplish by mechanical means what nature effects by a mere change of temperature. We ex- press a certain quantity of caloric from the air, while its affinity for that substance remains undiminished. Remove the restraint, and, the affinity exerting itself, a sudden in- crease of volume takes place, exhibiting that phenomenon which is usually called elastic force. Again: When a foot-ball is struck (and so of similar cases) there is a displacement of caloric proportioned to the force applied and the nature of the covering. ' But this 1s only momentary ; for, the affinity of the air for caloric re- maining unaltered, a quantity of the Jatter, more than equal to what was displaced by the blow, is, for the reason betore ~ pointed out, instantly taken in by the air, and with such rapidity as to cause the ball to recoil from the foot in the same manner as a hammer does when struck on.an anvil, but in a much more remarkable degree; for the recoil will always be proportioned to the force employed, compared with the affinity of the bodies for caloric. — Before concluding, we may observe generally, that every body in nature may be considered as in some measure elastic, though many of them cannot manifest that property to the extent which . those bodies usually called elastic can + that is, a certain force may be applied to all of. them with - out destroying their form, and by the application of that force a certain quantity of caloric may be first accumulated in and then given off from them, In every case of this Kind (and they include every species of friction) caloric is K 4 first 5g On the Production of Muriates first expressed from, and then imbibed, with a surplus quantity, into the parts of the body which undergo the mechanical action, and it is this circumstance which has so much puzzled some philosophers in certain experiments on friction. But as we may possibly lay before the society at a future period a few thoughts confined principally to this object, we forbear entering further into it at present. ee XXIII. On the Production of Muriates by the Galvanic Decomposition of Water: with a second Letter on the Subject from Mr. W, Prt, of Cambridge. In onr last volume, page 279, we laid before our readers a letter from Mr. Peel, of Cambridge, announcing the pro- duction of muriate of soda by the Galvanic decomposition of water. That communication we considered as extremely important, and we suggested that such experiments as Mr. Peel was engaged in, might possibly lead to some know- | ledge of the composition of soda and the base of the mu- riatic acid. : isd The letter alluded to was dated the 23d of April last, and published in our number for that month. We have been not a little gratified since in finding that our suspicion has been in some degree confirmed by M. Cuvier’s report of the labours of the Class of the Mathematical and Physical Sci- ences of the French National Institute from the 20th of. June 1804 to the 20th of June 1805, published on the 25th of the Jast-mentioned month *. One of the articles of this report states, that M. Pacchiani, of Pisa, has discovered the radical of the acid in question, which he states to be hydrogen. By taking from water, by means of the Gal- vanic pile, a portion of its oxygen, he asserts that the water was converted into oxymuriatic acid; and that, conse- quently, ‘¢ muriatic acid is hydrogen at its minimum of oxidation ¢; the oxymuriatic acid, hydrogen in the middle state; and water, hydrogen at its maximum of oxidation.” The following letter was intended for our last number, but did not reach us in time. It will be found as interest- ing to our philosophical readers as Mr. Peel’s former com+ munication. - The result of his new experiment, so far as ‘ ’ * Part of this report is given in our present Number. + In our 6th vol. p. 153, we announced that Girtanner maintained hydro= gen to be the cnet of the muriatic acid, and that this acid contained less oxygen than water. : the ly the Galvanic Decomposition of Water. - 153 the muriatic acid is concerned, is the same as that before communicated ; but in this instance he has obtained a dif- ferent alkali,—a kind of proof that the alkalis, as has for some time been suspected, are not essentially very different from each other. Cambridge, June 4, 1805. “e'StR, «© Acccording to my promise I send you another letter, which I hope will be as favourably received as my last. Permit me to say, I feel myself much indebted to you for your suggestions *, which have led me to the disvovery I now send you. ** Having proceeded to the formation of water from its elements, with which to repeat my former experiment, I found, when the oxygen and hydrogen gases wére quite pure and exactly in due proportion, that no residuum of air was left, and that the water formed was not in the slightest degree acidulous. When the process was not conducted with great ‘accuracy, or any precaution to have it accurate was omitted, I then found the water acidulous, and the acid that caused this acidity to be the uitric acid. “© The acidulous water thus obtained I neutralized with lime, from which I distilled the water, and this water I de- composed by the Galvanic process, as in the experiment detailed in my former letter. “¢ J did not imagine the using water so obtained could make the least differeice on the result of the experiment ; but as you had expressed a wish to have the trial made, I again undertook tha interesting but very tedious labour. ‘* When I came to examine the residuum, to my great astonishment I found that not muriate of soda but muriate of potash was produced ! ‘* J must own I feel myself entirely at a loss how to ac- count for this, nor shall I attempt it. All I can say is, that this, as well as my former experiment, was conducted with the greatest care and accuracy that I could bestow. Perhaps your, or some of your readers’, superior sagacity may furnish some hint that may lead to a satisfactory ex- planation of the phenomena. Iam, &c. “To Mr. Tilloch. 6W. PEEL.” Our readers, we are persuaded, will agree with Mr. Peel in thinking the result, indeed, very singular. Some may, perhaps, be inclined to believe there must have been some * See Note, vol. xxi. p, 280. a mistake / 154 On the Production of Muriates. mistake in the experiment detailed in this or in the former letter; but till some person possessed of as much ingenuity and patience as Mr. Peel shall prove bis experiments to be. erroneous, we shai! not question their accuracy *. | Indeed, we had a suspicion that the result might possibly be affected by using water obtained from different sources, or distilled from different substances, and it was this suspicion that induced us to recommend to Mr. Peel a repetition of the experiment under new circumstances. We may remark here, that Guyton suspects potash to be composed of lime and hydrogen. In the present expe- riment lime was employed to neutralize the acid in the water made use of; and though the water was distilled from the lime, it does not appear to us impossible that a sr.atl portion of it might be carried over, Indeed, if Guy- ton’s opinion be well founded, it is very probable this was the case. Hydrogen the water would furnish by its de- composition. We have not been informed of the nature of the residuum left by distilling the water made use of in Mr. Peel’s first expertinent; that is, what substances were. held in solution by it—if spring watér. It would be a curious circumstance if it should prove to have been combined with a little mag- nesia, as it would go some length in proving the truth of another opinion of Guyton, that soda is composed of mag- nesia and hydrogen ; for it would only be necessary to sup~- pose that in the distillation of the water there was carried over some of the magnesia, a véry minute portion of which, other circumstances coinciding, might be all that was wanted to determine the kind of alkali to be formed. Could the result depend at all on the circumstance of nitric acid having been previously in mixture with the water? In the productian of nitre (nitrate of potash) from the corruption of anima] and vegetable substances, possibly the previous formation of the acid from its elements has some share in determining the formation of that alkali for which it has the greatest affinity. If the acidulous water employed in the last experiment had been distilled per se, or from some other substance than lime, would the result have been different? From Mr. Peel’s experiments it seems extremely probable that very small and seemingly inappreciable differences in the way of * We wish Mr. Peel had mentioned the tests and methods he made use of to ascertain the nature of the products he obtained. We are certain such information, in addition to what he has already given, would prove ac- ceptable to our philosophical recders, conducting ’ Facts applictlle.to.the. Theory ofthe Earth. 135 onducting such: labours, may determine the production of tvery different substances. s In short, it seems probable that some of those substances ewhich in the present state'of our knowledge we are obliged -to consider as the mest: simple elements, such as oxygen, hydrogen, and azote, are, in fact, compounds’s,.and if so, the formation of one or more of these may take place under circumstances in which we should not expect them to be present, and may produce such results as those now under ‘consideration. . This subject is extremely interesting, and we hope Mr. Peel and other philosophers will continue to give it that attention which its importance sceims to demand.—A. T. = XXIV. Memoir on some xoological Facts applicable io the Theory of the Eurth.. Read in the Physical and Mathe- matical Class of the French National institute on the 22d of October 1804.' By M.Prron, Naturalist to the Ex- pedition for making Discoveries in Australasia *. Colles exire videntur; : Surget humus; cresctnt loca, decrescentibus undis, , : Ovid. Mct. lib. }. ver.342. I; excursions confined to the countries of Europe can fur- nish matter for so many useful works and for so many va- luable comparisons, and if slight differences in the physical constitution of the soil, in its temperature, and in.its pro- ductions, could give rise in all ages to grand ideas and 1m- portant theories, how fertile in the most valuable results of every kind must be distant navigations ! The traveller in voyages of this kind, transported, as we may say, on the wings of the wind, traverses in a few months the most different climates; distances vanish, and small .differences disappear along with them. ‘The large masses alone can strike him; and they are every where re-~ produced with an opposition, and contrasts so great and so numerous, that the coldest imagination cannot fail to be jnterested in such.a spectacle. In one place, the summit of the Peak of Teneriffe, which bas been rendered celebrated by the valuable researches of M. Humboldt, seems to un- fold before him the history of the grand catastrophes of na- ture, and of their effects ; while in another he sees rising at * From the Journal de Physique, Trimaire, an 13, the 156 ' Om tome zoological Facts the extremities of the Austral world those bulwarks of gra- nite which she seems desirous of opposing to the fury of the boundless ocean. He soon arrives on the barren coasts of the west and north-west side of New Holland, where the phenomenon of the acquisitions made by the land pre- sents itself with all the interest of which it is susceptible. Tn vain does he pass along coasts of two or three hundred leagues in extent; he every where observes eternal downs of white sand, which extend into the country as far as one ean penetrate. The numerous islands he meets with exhibit -to him a similar constitution; and the banks of sand, so frequent in these dangerous seas, have no other. But the fertile mountains of Timor already begin to appear 5 an eternal vegetation every where covers them with its rich productions : : they are continued in large gradations, which rise more and more towards the interior of the land. Every thing is new in its aspect: he no longer sees those lacerated forms, those blackened peaks, and those threatening craters of Teneriffe, and of the Isles of France and of Bourbon ; those striking and majestic masses of South Cape, Cape Pelé, and Cape Frederick-Henderick in Van Diemen’s Hand; much less that monotonous and tiresome aspect of the sandy coasts of New Holland. None of these pictures are applicable to the mountains of Timor. Their forms, though large, are softened ; their prolongations are regular their summits are broad, andl sink down gradually by slight undulations, which disappear on the sea shore: in a word, every thing announces here the tranquillity of the tropics, and the peaceful action of nature and of time. Amidst objects so grand, with terms of comparison so prodigious, the study of nature then more striking, is also more easy : all the petty objects of detail, the modern effects of a multitude of secondary causes, disappear, as we may say, before the grand ensemble of nature, and cease to oc- eupy in our annals the too important part which they have been so many times made to perform. But we may | safely affirm, that we shall have-no real theory of the earth till the glorious period when the sciences can reckon among their votaries men desirous of emulating Humboldt. What he has done in regard to America ought to be done in re- ard to many distant countries and so many archipelagos still unknowit. At the head of the latter appears New Holland, an immense country, hitherto little explored, but worthy of the attention of the governments much more than ths naturalists of Europe. . SECTION applicable to the Theory of the Earth. 157 ‘ Section I. Zoological Observations which may excite Doubts in regard to the primitive Union of New Holland and Van Diemen’s Land. Of all the observations which may be made in proceeding from Van Diemen’s Land to New Holland; the easiest, ne doubt the most important, and perhaps also the most in= explicable, is, the absolute difference of the two races who inhabit these two lands. If we except, indeed, the meagre- ness of the extremities, which is observed equally among both people, they have scarcely any thing common in their manners and customs, in their rude arts, in their imple- ments for hunting or fishing, in their habitations or piro- guas, in their arms or language, in the whole of their phy-— sical constitution, in the form of the cranium, or in the proportions of the face. This absolute dissimilarity appears also in the colour: the inhabitants of Van Diemen’s Land being browner than those of New Holland; it appears also in a character hitherto considered as exclusive, namely, the nature of the, hair. That of the inhabitants of Van Die- men’s Land is short, woolly, and curled; that of the New Hollanders straight, lank, and stiff. Now how can it be conceived that an island of 60 leacues in extent at most, so near to an immense continent, situ- ated also at the extremities of the Austral world, and sepa- rated from every other known land by the enormous di- stances of five, eight, twelve, and even fifteen hundred - leagues, should have a race of men altogether different from that of the neighbouring continent? How can we conceive this exclusion of all relation, so contrary to our ideas in regard to the communication and transmigration of nations ? How can we account for the darker colour, and curled woolly hair, in a country much colder? It appears to me difficult, I confess, to assign a satisfactory reason for these anomalies. Ail these curious facts, which will be detailed in the general account of our long voyage, will be new proofs of the imperfection of our theories, which are always suited to the state of the knowledge of the age which gave birth to them. At present I must be contented with de- ducing from this first part of my observations the important consequence, that the separation of Van Diemen’s Land from New Holland is not one of the modern operations of nature; for it is probable that if these two countries had been formerly joined they would have had the same race for inhabitants, and it would no doubt have been that which occupies, 2S On some zoological Facts occupics, with its ferocious tribes, the woot: of the im- mense coasts of New Holland, from Cape Wilson to. the burning coasts of the land of Apihelin and ca great gulf of Carpentaria. ; Another zoological sch tend’ still further to eons this: distinction, if not primitive at least very old, between New Holland and Van Diemen’s, Land... The dog, that. animal so valitabte to man, the faithtul companion of his misfor- tunes, his travels, and dangers, the mdefaugable istrument of bis distant hunting excursions, every where:so common on the continenty and whichiwe found onal} its coasts with the different antes we had an opportunity of seemg, does not exist in Van Diemen’s Land ; at least we ¢ould observe no traees of this animal., -We never saw any, of them with the inbabitants, notwithstanding out daily imtercourse with them. The case was the same with, Mv Labillardiere during Dentrecasteanx’s voyage; and. it does not; appear that any other traveljcr ever/saw any. The E nelish whale fishers, whom | consultedon the s subject, confirmed this circum- stance, that the dog is not found in Van: Diemen’s Land. ; Section IT: Zoological Observations which seem, to,; mudicate that the Snammits of the Mountains of Van Diemen’s Land, New Hoiland, and Timor, were formerly covered bly the Sea. One of the noblest and at the same time most incontest- able results of modern geological researches 13, the certainty of the sea having once stood at very considerable elevations above its present ‘level. In almost every point of the old continent the proofs of this fact are as numerous as they are evident. » They appear with interest in different parts of the neweworlds ; and M. Humboldt has lately communicated to us a very curious circumstance of this kind. In this point of view, as well as in many others, New Holland and Van Diemen’s Land remained to be examined; as they might - have formed an exception of sufficient importance to induce a very rigorous philosopher to deny the universality of the antient domination of the ocean, however favourable reason= ae and analogy might be toit. Fortunately this deficiency sone of those w hich, depending only on the existence of a fae could be easily supplied : ; It appears to me that it is completely so at present. On Van Diemen’s Land indeed, mn several points of New Holland, and on the summits of the mountains of Timor, I every cs Me? met with those va~ luable remains, which may be considered as irrefragable tes- timonies of the revolutions of nature. In applicable to the Theory of the Earth. 159 Jn the rapid view which I am‘going to take of my results in this respect, I shall treat in succession of what relates to fossil shells and zoophites. One of the principal reasons of this distinction, the importance of which I shall soon have occasion to. prove, is the almost absolute exclusion of every large kind of solid zoophites after the 34th degree of south latitude, beyond which I observed only the difficult and orbicole tribes of the sponges, the alcyons, flustres, and some millepores. A. Petrified Shells. It would be too tedious and useless to enter here into the details of all my observations on this subject: it will be sufficient for me to. give an account only of the principal results. At Van Diemen’s Land, towards the bottom of the North River, I observed, at the height of six or seven hundred feet above the Jevel.of the sea, large masses of petrified shells, all belonging to the dime genus of Lamarck, and constituting a species to which I could find none living analogous in the same places. On several points of the east coast of the island Maria there are seen regular horizontal strata, consisting of a kind of whitish shelly freestone resting on granitic rocks, at the height of four or five hundred feet above the level of the sea. At Kangaroo Island, those of St. Peter and St. Francis, and that portion of the continent situated behind them, I made similar observations: I found always some remains of petrified shells, at a ereater or less distance, in the in- terior of the country, and at heights more or less consi- derable. Vancouver and Mainzies had before observed some in Port King George, and in that point also I myself collected several specimens. During the interesting excursion which my friend M. | Bailly made into the interior of New Holland, ascending Swan’s Riyer for about twenty leagues, he found every where, as he told me, the ground covered with quartzy sand mixed with the remains of shells. S At the Bay of Seals this phenomenon occurs with more decisive characters. The whole substance of the barren isles of Dorré and that of Dirk-Hartog consist of freestone, sometimes reddish and sometimes~-whitish, filled with shells of different kinds. This composition becomes still more striking at Timor. 7 On 160 On some xoological Facts On the summit of those moimtains, already mentioned; there is found, at the height of more than 15 or 1800 feet above the level of the sea, a great number of shells incrusted in the middle of the madreporic masses which they form: The most of these shells are in the siliceous state; some of them, still in the calcareous state, are more or legs altered and friable. There are some monstrous ones among them: T have seen several individuals, and every person belonging to the expedition might have seen them also, which were not less than four or five feet in length. All these large shells evidently belonged to the genera Aippope and tridacne of Lamarck; and, what is more important, the fossil in- dividuals have such a resemblance to those of the same genus found aliveon the sea shore at the bottom of the mountains, that I have thought proper to consider them as the same in my General Topography of the Bay of Cou- pang. Even the gigantic proportions of the fossil éridacnes are found in the “living ones. I myself saw a valve which served daily as a trough to five or six hogs. In the Dutch fort there is another in which the soldiers of the garrison wash theirlinen. The absolute want of colour, common to the fossil and living tridacnes, is another reason for their identity. The case was the same with several kinds of zoophites, which, existing still on the coasts, seem to be so identic with some of those forming the mountains of that part of the island, that I made no hesitation in con- sidering them as such. Since my return to Europe, how- ever, having had occasion, in examining the beautiful col- lection of M. Defrance, to remark how easy it is to be mistaken in this respect, I must freely confess that I can no longer venture to warrant this identity, however pro- bable it may appear, as my observations were not made with that minute attention which the subject deserves, and as whole specimens are not to be found in our collections. While I regret that I suffered so valuable an observation to escape me, I must mark Timor as the place most proper for determining the delicate and interesting question \in regard to analogous living individuals, at least in the last classes of the animal kingdom. Before I terminate what relates to petrified shells, it seems to me indispensably necessary to say a word of in- crusted shells, which are too often confounded with the former. B. Of applicable to the Theory of the Earth. 161 B. Of Incrustations of different Kinds, and particularly thé incrusted Shells found in different Parts of New Holland. One of the particular advantages of extensive navigations and long voyages is, that the theatre of observation is so much varied, and objects so multiplied, that nothing is often wanting but a sound judgment to make the most difficult comparisons, and to deduce from them important consequences. What man, for example, can see, with indifference, around him that succession of beautiful in- crustations so frequent on the shores of Kangaroo Island, on those of the Archipelago, of St. Peter and St. Francis, and on the shores of the immense Bay of Seals? In one place whole trunks of shrubs are entirely covered with a mixed stratum of freestone and calcareous matter, and in others are accumulated branches of trees, roots, shells, zoophites, the bones of animals, and excrements of qua- drupeds, concealed under the same covering. One might be tempted to believe,” said the unfortunate Riche, ** that a new Perseus carried the head of Medusa over these distant coasts.” On the sight of so many striking singularities, how can we forbear inquiring into the cause, and how is it possible that it should not be discovered in the particular nature of the sand on these shores? The numerous shells, indeed, produced in these seas being continually rolled by the action of the waves on the neighbouring shore, are thus reduced to very small fragments, which being: afterwards mixed with the quartzy sand, soon form with it a calcareous cement of a superior quality. In carefully examining its materials one might be tempted to believe that Dr. Higgins, in his ingenious Essay on Calcareous Cements, had stolen the secret of nature. The proportions, indeed, which he indicates as susceptible of forming the most solid combina- tion, that is, one part of lime and seven of quartzy sand, are those which nature seems to have adopted for her ce- ment. But whatever this composition may be, it is the only agent of those remarkable incrustations of which I have spoken. On the shore it soon incrusts every body thrown upon it; testacea, zoophites, galets, are all agelu- tinated by it. The observer sees, as we say, formed before his eyes, the breches and puddingstones of which the neigh- bouring rocks are composed. Transported by the winds, this active matter deposits itself on the nearest shrubs. At first it is only a light kind of dust, which soon becomes solid around the stem which it embraces. From that mo- Vol. 22. No. 86, July 1905. I ment 162 On some xoological Facts ment the mode of the nutrition of the vegetable becomes changed; it soon languishes, and, though still alive, it seems to have undergone a kind of general petrification. T have brought home a great many fine specimens of this sort, and the difficulty of transporting them alone prevented me from bringing back a more considerable number. What is most singular in'this operation of nature is, the speed with which this kind of metamorphosis 1s effected. Thave reason, indeed, to believe, from my own observations, that a shell, a month after its being cast on the shore, can no longer be distinguished. The force of the solar rays, the vivacity of the light reflected by the white sand of the coast, are sufficient in a few days, with the sea water, to deprive it of its colour, and to disorganize it im such 2 manner, that in the middle of the calcareous stratum which has already seized it, the most experienced eye might mis- take it, and range it in the class of the oldest petrified shells. One may judge of these alterations by the different spect- mens—how easily this mistake may be committed, and how impossible it would be to assign to the most of these shells a character proper to distinguish them from real fossils. C. Of Zoophites olserved at great Heights above the pre- sent Level of the Sea. I have now concluded what relates to petrified shells, or those merely incrusted: it is seen, that from the most southern extremity of the eastern hemisphere to the middle of the equatorial regions they are found in greater or less numbers, and at greater or less heights. The case is not the same with solid zoophites: as already said, I could not find large species beyond the 34th degree of south latitude; and it does not appear that any other traveller observed any con- siderable number of these animals beyond the same point, either in the northern or the southern hemisphere. Driven, as we may say, from the one extremity of the world to the other, it is in the bosom of the warmest seas that this in- numerable family of animals seem to have fixed their habi- tation and their empire: it is the latter zone in particular which gives birth exclusively to those formidable reefs, those numerous islands, those vast archipelagos, prodigious monuments of their powcr. All the Society Isles, Maitea, Tongataboo, Eona, Anamooka, Turtle Island in the Pa- cific Ocean, New Caledonia, Chain Islands, Tethuroa, Tioukea, Palliser’s Isles, Tupai, Moopehea, the Isle of Cocos and that of Pines, Norfolk Island, How’s Island, Palmerston Isles, several of the New Hebrides, Mallicolo, > sdhe applicable to the heory of thé Earth. 163 the archipelago of. the Low Friendly Isles, Bougainville’s Island, several points of New Guinea, all the islands scat- tered on the eastern side of New Holland, and in particular the formidable labyrinth which had like to have proved so fatal to the vessels of Bougainville and captain Cook ; in a word, almost all those innumerable islands dispersed throughout the great equinoctial ocean, seem some of them entirely, and others only in part, to be the work of these feeble animals. The accounts of all the navigators who have traversed these seas are filled with expressions of the terror inspired by their labours. All of them, almost, were exposed to the.greatest dangers in the midst of the reefs which they raise up from the bottom of the ocean to its surface, and no doubt the unfortunate navigator, the loss of whom France as well as all Europe deplores, was one of their numerous victims. .... . *¢ The danger they present,” says M. Labillardiere with great reason, ‘* is.the more to be apprehended as they form rugged rocks covered by the waves, and which cannot be perceived but at very short distances. Ifa calm comes on, and the ship is driven towards them by a current, her loss is almost inevitable: in vain would the crew attempt to save her by dropping their anchor; it would not reach the bottom even quite close to these wails of coral, which rise in a perpendicular direction from the bottom of the waters. These polypiers, the continual increase of which obstructs more and more the bason of the seas, are capable of frightening navigators; and many shallows, which at pre- sent afford a passage, will soon form shoals exceedingly dangerous.” . . Though less common in the seas which we traversed, these animals furnished me nevertheless with subject of observations the more valuable, as the general consequences deduced from them may be applied with more interest and more evidence to the history of the revolutions of our planet. . _ Thus, as I have said, from the 44th to the 34th degree south, no large species of solid zoophytes are found, It is at Port King George, in Nuyts Land, that these animals appear, for the first time, with those grand characters which they affect in the midst of the equinoctial regions. My particular observations, indeed, are reduced in this point to mere fragments, found here and there in the interior parts of the earth. The case is not the same with those of Main- ‘zies and Vancouver. The details, for which we are indebted to these navigators, are too valuable of themselves, and pars L2 ticularly 164 On some zoological Facts ticularly on account of the consequences with which they will furnish us, that I cannot here forbear transcribing what Vancouver has said on the subject. « The country,” says he, ‘is formed chiefly of coral, and it seems that its elevation aboye the level of the sea is of modern date; for not only the shores and banks which extend along the coast are in general composed of coral, since our lead always brought up some of it, but rt was found also on the highest hills we ascended, and in parti- cular on the summit of Bald Head, which is at such a height above the level of the sea, that it is seen at the distance of ‘twelve orf> urteen leagues.. The coral here was in its pri-~ mitive state, and especially on a level field of about eight acres, Which did not produce the least blade of grass amidst ibe white sand with which it was covered, but from which arose branches of coral exactly similar to those exhibited by beds of the same substance above the surface of the sea, with ramifications of different sizes, some half’an inch at Jeast, and others four or five inches in circumference. Many of these coral fields, if I may use that expression, are to be met with: a large quantity of sea shells, some perfect and still adhering to the coral, and others at different degrees of dissolution, are observed in them. The coral itself was more or less friable; the extremity of the branches, some of which rose more than four feet above the sand, was easily reduced to powder. In regard to the parts which were near or below the surface, a certain degree of foree was necessary to de- tach them from the foundation of rock from which they seemed to arise. I have seen coral in many places at a con- siderable distance from. the sea, but F never saw it any where else so high and so perfect *.” This, no doubt, is one of the most curious faets of this kind, as well as one of the most important to be verified and to be examined. Will it now be believed that the two vessels belonging to our expedition, the Geographe and the Casuarina, remained for nearly a month at anchor in Port King George, at the foot, as we may say, of this Bald Head, so valuable to be visited, without any of the three naturalists, who still remained on board these vessels, being permitted to go thither? Fortunately the large island of Timor presented a field still wider and more striking for observations on zoophytes. There every thing attests their power, and the revolutions effected by them in nature. They are found on the summits * Vancouver’s Voyage, vol i: of applicable to the Theory of the Earth. 163 of the highest-mountains of Coupang, and they are easily distinguished: in the deepest caverns, and the widest fis- sures, they present a tissue, the characters of which cannot escape notice. In the excursion, so painful and so laborious, undertaken by me and my friend Lesueur, to hunt crocodiles at Olinama, we every where observed the same composi- tion; at Oba, Lassiana, Meniki, Noebaki, Oebello, and Olipama. At the Jast-mentioned point we found ourselves opposite to the grand chain of mountains of Anmioa and Fatelou, the back of which is uninhabitable on account of the prodigious number of crocodiles which live in the smarshes of that part of the coast. This broad plateau, which commands all that portion of Tymor, is entirely composed of madreporic matters. From Oéana to Pacoula the whole country, according to the inhabitants, is lime- stone; and this is unanimously confirmed by the Dutch. Tt is not only im this state of death and inactivity that the zoophytes of Timor ought to excite admiration and interest they encumber, in the living state, the bottom of the sea; every where in the Bay of Babao they raise up reefs and aslands.. Turtle Island (Rea Pouwdlou), Birds Island (Bowrou Poulou), and Monkey Island (Codé Poulaw), are exclusively their work. Long narrow reefs, which preceed from Point Simao, confine more and more the entrance of the bay in that quarter. They render inaccessible the coasts of Fa- toumé and Soulama, and promote ‘the increase of the land gained from the sea in all these pojnts. On the coast of Osapa one may already, at low water, advance to the di- stance of more than three-fourths of a league on the shore abandoned by the waves: it is there that, with a mixture of astonishment and admiration, one may enjoy at ease the wonderful spectacle of thousands of these animals inces- santly employed in the formation of the rocks on which one advances. All the genera are assembled at the same time at the feet of the observer; they press around him ; their singular and fantastical forms, the different medifiea- tions of their colours, and those of their organization and their structure, attract, in turn, his attertion and medita- tions ; and when, provided with a good magnifying glass, he contemplates these beings, so weak he can scarcely con- ceive how nature, by means so small in appearance, should be able to raise up from the bottom of the sea those vast ridges of mountains which are continued over the face of the island, and which seem to form almost its whole sub- stance. At Timor it would be easy to make a long series of observations on these interesting animals; the profound L3 calmness . 166 Short Account of the Life calmness of the sea, its high temperature, the nature of the shore, on which one may advance at Jow water, as already mentioned, to a very great distance, having the water scarcely up to the knee; the great abundance of these ani- mals, and their variety, are all favourable to researches of this kind: they may be observed, described, and drawn im their natural state, as the water does not rise above them to the height of more than a few centimetres, or sometimes only millimetres; they may be seen in their state of con- traction or extreme development; one may observe, also, their progressive increase, and its boundaries: im a word, there can be no doubt that a labour of this kind, undertaken by one or more enlightened naturalists, would contribute, in the most effectual, manner, to the advancement of this part of natural history so little known, and which deserves so much to be carefully examined. [To be continued.] XXV. Short Account of the Life of the late Dr. PRIESTLEY. ; Joszrn PriestLeEy, LL.D. F.R.S. and member of many foreign literary societies, was born at Field Head, near Leeds, in Yorkshire, on March 13, old style, in the year 1733. His mother died when he was very young; and his father, who was engaged in the cloth manufactory, marry- ing again, and having a large family, Joseph, when eight years of age, was taken into the house of a near relation, a lady eminent for piety and benevolence, who adopted and educated him as her own son. He acquired the rudiments of the Latin and Greek lan~ guages under the instruction of Mr. Hague, a respectable clergyman, master of a free grammar school in the neigh- bourhood, and during the vacations he applied to the study of the Hebrew, Chaldee, and otker oriental languages. By the assistance of Mr, Haggerston, who had been a pupil of the celebrated Maclaurin, he made a considerable proficiency in geometry, both speculative and practical algebra, and natural philosophy. He acquired also some skill in modern Janguages, in order to qualify himself for a merchant’s counting-house, the delicacy of his constitution rendering it at one time doubtful whether he would be able to pursue his studies for a learned profession, . Tn hjs nineteenth year he entered as a student of divinity ; at of the late Dr. Priestley. 167 at the academy of Daventry, which was the successor of that kept by Dr. Doddridge, at Northampton, and was con- ducted by Dr. Ashworth, whose first pupil young: Priestley is said to have been. When about the age of twenty-two he was chosen assistant minister to the independent con- gregation of Needham-market, in Suffolk; and after a stay of three years at that place, he accepted an invitation to be pastor of a small congregation at Namptwich, in Che- shire, where he opened a day school, in the management of which he exhibited that turn for ingenious research and that spirit of improvement which were to be his distinguishing characteristics. He enlarged the minds of his pupils by philosophical experiments, and drew up an English gram- mar on an improved plan, which was his earliest publica- tion. On the death of the reverend Dr. Tayler, the tutor in divinity at Warrington academy, Dr. Aikin was chosen to supply his place, and Mr. Priestley was invited to under- take the vacant department in the belles lettres. He ac- cordingly removed to Warrington in the year 1761, and soon after married a daughter of Mr. Wilkinson, of Ber- sham foundry, near Wrexhain, a lady of an excellent heart and a strong understanding, and the faithful partner of all the vicissitudes of his life. At Warrington the literary career of this eminent person properly commenced, and a variety of publications soon an- nounced to the public the extent and originality of his ta- lents. One of the first was a chart of biography, in which he ingeniously contrived to present au ocular image of the proportional duration of existence, and of the chronological period and synchronism of all the most eminent persons of all agés and countries, in the great departments of sci- ence, art, and public life. The favourable reception which this work experienced suggested a second chart of history, which exhibited in the like manner the extent, time, and duration of the different states and empires. Having long amused himself with an electrical machine, and taken an interest in the progress of discovery in that branch of physics, he was induced to undertake a History of Electricity, with an account of its present state. It ap- eee from his preface, that while engaged in this design he ad enjoyed the advantage of personal intercourse with some eminent philosophers, among whom he acknowledges as coadjutors Dr, Watson, Dr. Franklin, and Mr. Canton. The work was first published at Warrington in 1767, 4to; and so well was it received that it underwent a fifth edition L4 in 168 Short Account of the Life in 4to in 1794. Itis, indeed, an admirable model of sci- entific history ; full without superfluity, clear, methodical, candid, and unaffected. The original experiments detailed in it are highly ingenious, and gave a foretaste of that fer- tility of contrivance and sagacity of observation by which the author was afterwards so much distinguished. His connection with Warrington ceased in 1768, at which time he accepted an invitation to officiate as pastor to a large and respectable congregation of protestant dis- senters at Leeds. The favourable reception his History of Electricity had experienced induced him to adopt the grand design of tracing out the rise and progress of the other sci- ences in a historical form, and much of his time at this lacé was employed in his second work of this kind, enti- tled “* The History and present State of the Discoveries re- lating to Vision, Light, and Colours ;” which appeared in two vols. 4to, 1772. This work, though possessed of con- siderable merit, did not attain to the same popularity as the History of Electricity, and proved to be the termination of his plan: but science was no loser by this circumstance, as the activity of his mind was turned from the consideration of the discoveries of others to the attempt of making disco- veries of his own; and nothing could be more brilliant than his success. It appears that at this period he had begun those experiments upon air which have given the greatest celebrity to his name as a natural philosopher. In 1770 Dr. Priestley quitted Leeds; and having been recommended by his friend Dr. Price to the late marquis of Lansdown, then earl of Shelburne, he lived with his lordship in the capacity of his librarian, or rather as his lt- terary and philosophical companion. During this period his family resided at Calne, in Wiltshire, adjacent to the country-seat of lord Shelburne: Dr. Priestley frequently accompanied his noble patron to London, and mixed at his house with several of the eminent characters of the time, by whom he was treated with every respect due to his cha- racter and talents. He also attended his lordship on a visit to Paris, where he was introduced to most of the celebrated men of letters and science in that capital. To give a detailed account of Dr. Priestley’s philosophical labours would require far more room than can be allotted to such an important object in a miscellany of this kind : we must therefore content ourselves with the following short notice. In the Philosophical Transactions for 1773 he pub- lished a paper containing observations on different kinds of air, which obtained the honorary prize of Copley’s medal. 3 These of the late Dr. Priestley. 169 These were reprinted, with many important additions, in the first volume of his Experiments and Observations on different Kinds of Air, Svo, 1774. A second volume of this work appeared in.1775, and a third in 1777. Some of the most striking of his discoveries were those of nitrous and dephlogisticated air, or oxygen gas; of the restoration of vitiated air by vegetation; of the influence of hight on vegetables ; and of the effects of respiration on the blood. By these publications Dr. Priestley’s fame was spread throughout ail the enlightened countries of Europe, and most of the scientific bodies of Europe were ambitious to rank him among the number of their members. . 5, . . The term of his engagement with lord Shelburne having expired, Dr. Priestley, with a pension of 1501. per annum, was at liberty to choose a new situation. He gave the pre~ ference to the populous town of Birmingham, induced chiefly by the advantages it afforded from the nature of its manu- factures to.the pursuits of chemical knowledge. It was also the residence of several men of science, among whom the names of Watt, Withering, Bolton, and Keir, are well known to the public. With these he was soon upon terms of friendly intercourse; and their Lunarian Club presented a constellation of talent which would not easily have been collected even in the metropolis. He had not resided long at Birmingham when he was invited to undertake the office of pastor to a congregation of dissenters near that town, upon which he entered towards the close of the year 1780. The disgraceful scenes which took place at Birmingham in 17y1,and which compelled Dr. Priestley to leave this situation as a fugitive, are well known to the public, and it 1s not our intention to revive the re- membrance of them by entering into particulars. Suffice it to say, that the doctor’s house, library, manuscripts, and ap- paratus, became a prey to the flames; and, though he re- ceived an indemnity for this loss, it was far from being an adequate compensation. The result of many years’ painful research and scientific labour perished by this shameful out- rage, which every friend to good order and justice deplored. For some time after this event Dr. Priestley lived as a wan-.. derer, till he was invited to succeed Dr. Price in a congre- gation at Hackney; but the persecution he had experienced from the infatuated rabble, added to some family reasons, induced him to leave his native country, and to embark for America in 1794. The place he fixed on for his residence in the new world was Northumberland, a town in Penn- sylvania, where having collected, by indefatigable pains, a valuable 170 ~=©Account of the Life of the late Dr. Priestley. valuable apparatus and well chosen library, he returned to his former pursuits. By many new experiments on the consti- tution of airs he became more and more fixed in the belief of the phlogistic theory, and in his opposition to the new French system of chemistry, of which he lived to be the sole opponent of note. The results of several of his inqui- ries on these topics were given both in separate publications and in the American Philosophical Transactions ; and it is bat fair to add, that the new theory is indebted to this op- position for some of the strongest proofs on which it is founded. ‘Dr. Priestley deciined the offer of the chemical professor- ship in the college of Philadelphia, which was made to him soon after his arrival in America; and likewise another offer, of succeeding the late Dr. Ewing as principai of the same college, in the spring of 1803; preferring a life of retire- ment and leisure, that he might devote himself entirely to philosophical and theological inquiries. While he lived at Northumberland he had the misfortune to lose an excellent wife, and a beloved and dutiful son. These afflictions, though severely felt, he bore with becoming fortitude and resignation. ‘Till the year 1801 he had enjoyed uninter- rupted good health, having scarcely ever known what sick- ness was ; but at that period he was attacked at Philadelphia by a constant indigestion, and difficulty of swallowing any kind of solid food. From about the beginning of Novem- ber 1803 to the middle of January 1804 his complaint grew more serious, and at one time he was incapable of swallow- ing any thing for thirty hours. In the last fortnight of Ja- nuary his legs swelled nearly to his knees, and his weakness increasing very much, he expired on the gth of February following. As theology is entirely foreign to the object of the Phi- Josophical Magazine, we have not thought proper to say any thing in regard to Dr. Priestley’s writings on that sub- ject, which are very numerous, nor the theological disputes in which he was engaged. His religious opinions are well known to the public, and therefore it is the less necessary for us to enter into any observations on them. The prin- cipal part of his other works are :—The History and present state of Electricity, with original Experiments, 4to: a fa- miliar Introduction to the Study of Electricity, 8vo: the History and present State of Discoveries relating to Vision, Light, and Colours; two vols. 4to, with many plates: Ex- periments and Observations on different Kinds of Air, and other Branches of Natural Philosophy connected with the , 6 Subject, Notices respecting New Publications. 171 Subject, 3 vols.: Experiments relating to the Decomposi- tion of dephlogisticated and inflammable Air, and on the Generation of Air from Water—a pamphlet: Heads of a Course of Lectures on Experimental Philosophy, including Chemistry: a tamiliar Introduction to the Theory and Prac- tice of Perspective, with copper-plates: a new Chart of History, cuutaining a View of the principal Revolutions of Empire that have taken place in the World; with a Book describing it, containing an Epitome of Universal History : a Chart of Biography, with a Book containing an Explana- tion of it, and a Catalogue of all the Names inserted in it: the Rudiments of English Grammar, adapted to the Use of Schools ; the same Grammar for the Use of those who have made some Proficiency in the Language: Lectures on His- tory‘and general Policy, to which 1s prefixed an Essay on a Course of liberal Education for civil and active Life, 4to: Observations relating to Education, more especially as it _ respects the Mind; to which is added an Essay on a Course of liberal Education -for civil and active Life: a Course of Lectures on Oratory and Criticism, 4to. The following were published after the doctor went to America :—Experiments and Observations relating to the Analysis of atmospherical Air and the Generation of Air from Water: the Doctrine of Phlogiston established, and that of the Composition of Water refuted. Reprinted with additions 1803. XXVI. Notices respecting New Publications. Da. Barton, professor of materia medica, natural his-- tory and botany, in the university of. Pennsylvania, has announced his intention to publish, in America, a new pe- riodical work, to be entitled ‘* The Philadelphia Medical and Physical Journal ;”’ to be published every six months. Dr. Young’s Course of Lectures on Natural Philosophy and the Mechanical Arts, delivered two years ago in the Theatre of the Royal Institution, is now printing, with con- siderable additions and improvements. The work will con- sist of two volumes, quarto ; the first containing the text of the lectures nearly as they were delivered, but with such alterations as are calculated to make them still more intel- ligible to the most uniutormed readers. The lectures are followed by a copious series of plates illustrative of every : department 172 French National Instituie. department of mechanical and physical science. The se- cond volume will contain, in the first place, the mathema- tical elements of natural philosophy deduced from first prin- ciples, and in many instances extended by new investiga- tions: secondly, a methodical catalogue of works relating to natural plulosophy and the arts, with about ten thousand references to parucular memoirs and passages, .and a num- ber of useful tables, and of concise abstracts and remarks: and lastly, a collection of the auther’s miscellaneous papers, reprinted, with some alterations, principally from the Phi- losophical Transactions. ‘The work is expected to be com- pleted early in the next winter. XXVIII. Proceedings of Learned Societies. FRENCH NATIONAL INSTITUTE. An Account of the Labours of the Class of the Mathema- tical and Physical Sciences of the French National Insti- tute from the 20th of June 1804 to the same Day 1805. By M. Cuvisr, perpetual Secretary. PHYSICAL PART. Atmost all the sciences which engage the attention of the society have this year made curious and important acquisi- tions; and, as is usual, chemistry has obtained the most considerable and most numerous. Count Rumford has examined heat under a new point of view. He has endeavoured to determine the force of the solar rays to produce it. The degree to which it is carried when its rays are concentrated by means of a burning glass is well known: but is their real power thereby augmented? or does the effect arise from their acting in greater number on a smaller space? To ascertain this, count Rumford in- vented a reservoir of heat, which is nothing else than a metal vesscl filled with water having a thermometer im- mersed in it: it receives the solar rays on one of its faces, which 1s blackened, and the water it contains acquires 2 certain degree of heat. Count Rumford suffers these rays to arrive sometimes in a parallel direction and sometimes concentrated by a magnifying glass; but bringing the latter nearer or making it recede in such a manner that the rays shall strike on a greater or Jess space of the surface of the vessel, though their quantity continues always the same. The French National Institute. 173 The water in the reservoir always acquires the same degree of heat nearly in the same time. Hence the power of the rays to produce heat is always proportional to their quantity whether they are concentrated or not; or, what amounts to the same thing, the heat produced is proportional to the light absorbed. It has long been believed that the heat of the earth does not all come from the sun, but that it is indebted for a great part of it to some focus concealed in its interior part: this is the old hypothesis of Descartes, which Button after- wards made the basis of othcr systems, M. Peron, sent by the Institute, as naturalist, with captain Baudin during his voyage of discovery, has made an extensive series of researches to ascertain the truth of this fact. He examined with an ingenious apparatus the temperature of the sea at different depths, and he every where found that it is colder the greater the depth. This result, agreeable to that before | obtained by English navigators im other seas than those trayersed by M. Peron, seems to destroy entirely the idea of acentral fire. It is even probable that the deepest abysses of the sea are always frozen, even under the equator, in the same manner as the summits of the highest mountains *. M. Biot has made a curious experiment in regard to the heat forced from bodies by compression. Oxygen and hy- drogen gas, when merely mixed at the ordinary degree of the pressure of the atmosphere, have need, in order to com- bine, of the action of the eleetric spark. When put toge- ther in a condensing machine they combined merely by the heat which was disengaged, and abandoned one so consi- derable at the time of their combination that the machine burst every time the experiment was repeated +. Common air, the medium in which not only the greater part of the phenomena of chemistry but those also of or- ganic life take place, cannot be studied too carefully by philosophers. Its degree of purity, that is to say, the pro- portion of oxygen it contains, is one of the most important points that can be examined. Messrs. Humboldt and Gay- Lussac have compared the different means hitherto invented for measuring this proportion, and have shown that the best of all is that of Volta, which consists in burning hy- drogen gas. A hundred parts in volume of oxygen are ne- * This reasoning is very inconclusive. For,if the earth contains heat that does not come from the sun, the water which it warms must ascend to the surface, being displaced by that which is colder, and consequently more dense.—Epir. + See Philosophical Magazine, vol. xxi. p. 35% eessary \ 174 French National Institute. cessary to saturate two hundred of hydrogen, whatever be the pressure and temperature. In’this manner one may discover the hydrogen contained in any air whatever, evert if it form only a three-thousandth part. Messrs. Humboldt and Gay-Lussac have ascertained that there does not exist a sensible portion of hydrogen in the lower part of the atmosphere; and the aérostatic excursion of Messrs. Biot and Gay-Lussac, and that of M. Gay-Lus- sac alone, during which he rose to a much greater height, have confirmed that there is no more at the greatest eleva- tion to which it is possible to rise, and far above that where the clouds are formed. Thus all the systems in which the formation of rain and other meteors was ascribed to the combustion of hydrogen gas, fall of themselves. There still remains some uncertainty in regard to the number of the new metals which are mixed with platina. Were any confidence.to be placed in the results hitherto announced, there would be, besides iron, copper, chrome, and lead, the metal discovered last year by Messrs. Fourcroy and Vauquelin, as well as by M. Descotils; two others found in it by Mr, Tennaut, and two discovered by Dr. Wollaston called rhodium and palladium. Dr. Wollaston, indeed, according to letters from Lon- don, discovered palladium, of which mention was made in my two last reports, and kept the discovery secret, as if to entrap chemists. He pretends that they have fallen com- pletely into the snare, by imagining that this metal was a compound of platina and mercury ; and, indeed, not only have the attempts of M. de Morveau to imitate palladium, according to the process of Mr. Chenevix, been unsuccessful, but the case was the same with three German chemists, Messrs. Rose, Gehler, and Richter. This palladium, there- fore, ought to be areal metal. Is the case the same with rhodium, osmium, and iridium? or do these substances enter into the composition of each other, or into those discovered by Messrs. Fourcroy, Vauquelin, and Descotils ? This question can be determined only by time. Chemistry, however, appears to have acquired a new metal named cerium, from the planet Ceres. It was the oxide of this metal which M. Klaproth considered as a new earth, and named ochroite. Two Swedes, Messrs. Hessin- ger and Bezelius, have supposed it to be a metallic sub- stance ; and M. Vauquelin, who repeated their experiments, is of the same opinion. Nevertheless, as he was not able to reduce it completely, some doubts still remain. We must leave also to time the confirmation of a disco- very Freneh National Institute. 175 very said, in a letter from Florence, to have been. made by M. Pacchiani, professor at Pisa, of the radical of the mu- riatic acid, one of the most important questions, without doubt, that still remain to be resolved in chemistry. M. Pac- chiani asserts, that he transfermed water into oxygenated muriatic acid by taking from it a part of its oxygen by means of the Galvanic pile. The murtatic acid then will be hy- drogen at its minintum of oxidation; the oxygenated mu- riatic acid, hydrogen in the middle state; and water, hydro- gen at its maximum of oxidation. Of all the objects of chemistry animal matters are the most embarrassing to it, on account of the great complica- tion of their elements, and because the simplest agent that can be applied to them produces in them a thousand move- ments and transformations, the play of which escapes us, and of which we judge only by the results. This is what takes place, for example, when these matters are treated with nitric acid,~a method first employed by Scheele and Bergman, and from which M. Berthoilet obtained so inte- resting results. ‘lhe most apparent phenomenon, then, is the development of a great quantity of azote. Those next observed are an alteration of the acid; the production of a great deal of ammonia, of carbonic, oxalic, aud malic acid ; and the transformation of a part of these matters into tallow, and of another into a yellow bitter substance. But these effects wary, according to the strength of the acid, the dura- tion of its action, and the nature of the matters subjected to it. Messrs. Fourcroy and Vauquelin, by directing their re- > searches to these variations, and the circumstances which attend them, have found that nitric acid apphed to the muscular fibre, that 1s to say, flesh, transforms it by a first impression into a yellow matter, little sapid, little soluble, and yet acid; by a longer continued action, into another matter, also yellow and acid, but very little soluble and ex- ey bitter; and, in the last place, into a-third matter, soluble but inflammable, and, what is very curious, deto- nating, not only in heat, like common gunpowder, but also by percussion. Indigo furnishes a similar matter, and still more abun- dantly than animal matters. Messrs. Haussman and Wal- ther had observed it for sometime. Messrs. Fourcroy and Vauquelin suppose it to be produced by the disappearance of azote, and by the combination of the hydrogen and carbon of the flesh with a superabundance of oxygen furnished by the acid. They suppose that the yellow matter which tinges the 176 French National Institute. the bile, and that which colours the skin and the urine during: the jaundice, is produced also by some combination of oxy- gen with the fibrine matter of the muscles, or with that of the blood. : Messrs. Fourcroy and Vauquelin have employed them- selves also on the analysis of milk; and their researches have greatly simplified the theory of it. They have discovered that the acid which is developed in it, and which was con- sidered to be of a particular nature, is nothing but the acid of vinegar modified by some animal substances and some salts which it holds in solution. Milk, according to them, must be considered as a mixed liquor, consisting of a great deal of water and of two kinds of matters, some of them really dissolved, as sugar, mucilage, muriate and sulphate of potash, and acetic acid; others merely suspended, as the matter of cheese, that of butter, and the phosphates of iron, lime and magnesia. Considering the infinite complication of this first alrment of young animals, these gentlemen give us new motives for admiring the providence of nature, which has deposited in it all the materials of speedy growth. The caseous sub- stance is almost the same as that of the muscles ; the phos- phate of iron is one of the elements of the blood; and that of lime forms the earthy basis, and is the cause of the hard- ness of the bones. These gentlemen also have made a remark which may be interesting to medicine: it is, that the whey does not con- tain phosphoric salts, but when it can dissolve them.in an excess of acid, and that it contains none when it is sweet. There are in chemistry some questions, which though on the first view they seem entirely particular, yet the solution of them may extend to so many different objcets that it might produce a revolution in the whole system of our knowledge. Such, for example, are the deposits formed by organized bodies of substances which we consider as simple, and which, as appears, these bodies, under several circumstances, could not acquire from without, but must have produced by combination. Do animals form lime, and vegetables argil and silex, as some naturalists assert? The generation of stones and that of mountains, and the whole history of our globe, depend in some measure on this problem. It is to it we may refer the analysis of the tabasheer, a kind of stony concretion which is formed in the bamboo. Messts. Fourcroy and Vauquelin have found, as was said some years ago, that it is almost pure silex. But how as silex French National Institute. ‘ 177 silex be dissolved, and absorbed by the plant? How could it circulate in the sap? For all this must have been neces- sary before it could be deposited in the knots of the stem. Messrs. Fourcroy and Vauquelin are of opinion that potash has served as the solvent, and that it has carried with it into the sap these particles of si!ex. According to them, there- fore, tabasheer proves nothing in favour of those who be- Jieve that silex can be produced merely by the act of vege- tation. : These indefatigable chemists have carried their researches to a phenomenon of disease in vegetation, interesting by its singularity, and long known by the damage it occasions. They have endeavoured, in consequence of a memoir pre- sented to the Institute by M. Girod-Chantrans, to deter- mine the nature of the smut in wheat. They have found in it an oil of a green colour and of the consistence of but- ter; phosphoric acid, in part combined with magnesia, and lime, and ammonia; charcoal, and a vegeto-animal sub- stance perfectly similar to that produced by the decomposi- tion of the gluten of wheat by putrefaction. They thence conclude that the smut is a residuum of farina decomposed by putrid fermentation, and suppose that it arises from a superabundance of animal manure, and a too hot and’ moist temperature at .”.e time of sowing, or when the grain is in flower. If agriculturists should acknowledge that these circumstances determine in reality a greater quantity of smuf, it might be possible to prevent, in some cases, this scourge. . Messrs. Fourcroy and Vauquelin have analysed likewise a mould found at the depth of more than fifty feet in some desert islands of the South Seas, and which is employed as manure on the coasts of Peru, where it is called guano. This analysis has so great a resemblance to that of pigeons’ dung, that there is reason to believe, with Mr. Humboldt, who brought this gziana to Europe, that it is nothing but the excrement of birds, which frequent these islands in im- mense numbers. This substance, as may be seen, is an object of very li- mited utility; but chemistry has long endeavoured to pro- cure one to agriculture which would be of more universal importance, namely, sugar extracted from indigenous plants. We gave an account, at the time, of the efforts of M. Achard, of Berlin, to obtain it from beet-root. M. Proust, a cele- Jebrated Spanish chemist, has extracted it from grapes; he has given a detail of the whole process in a memoir sent to Vol. 22, No. 86. July 1805. M us 178 = Formation of muriatic Acid by Galvanism. us from Madrid: hitherto, however, his sugar has neither. the whiteness nor the liardness, and has not entirely the taste of the sugar made from the sugar cane. According to recent intelligence from Germany, the pro- . .eess of M. Achard has been there much simplified; and this problem, so interesting in the present state of society, and which can scarcely fatl to change the state of nations, is not far from being solved. M. de Cossigny, a correspondent, has. endeavoured to get more directly to this result. He is of opinion that the’ sugar cane might be cultivated in the southern provinces of France. It has, indeed, been cultivated at Nicé for some time without producing sugar; but he asserts that this was owing to the juice being extracted too late, and to its hay- ing already undergone fermentation when boiled. He made very good sngar from canes cultivated in the Jardin des Plantes, but in a hot-house. We have already spoken several times of the labours of M. Seguin in regard to the chemical arts and medical che- mistry. He has continued them this year, and weated three important branches. He first employed himself on the analysis of opium, in order to determine which of its component principles it is that gives it its medical properties. Thi.’ celebrated juice: exhibited three very distinct substances: a little acetous. acid; another acid, which may be only the acetous or malic modified ; a crystalline matter which appears to be new; an extract soluble in water and in alcohol; another extract so- luble only in alcohol, acids, and alkalies; a vegetable oil a little concrete, and a sort of starch. Nothing remains but to try separately each of these substances, and to determine their respective effects on the animal body. M. Seguin is. employed on this at present, and he has promised that he will soon communicate to us the result of his observations. [To be continued.) XXVIII. Intelligence and Miscellaneous Articles. FORMATION OF MURIATIC ACID BY GALVANISM. Avrren that part of our present Number which contains the article respecting Mr. Peel’s experiments was at press, we received Number III. of the Edinburgh Medical and; Pet aah ‘ Surgical Formation of muriatic Acid by Galvanism. 179 Surgical Journal, published on the ist of July, to which was subjoined the following *© POSTSCRIPT, “¢ Containing an Account of the Discovery of the Com- position of Muriatic Acid. By Professor Paccuront, of Pisa. «¢ Since this number of our journal was completed, and indeed part of the impression sent to London, we have re- ceived a latter, dated 15th May 1805, from our -valuable and eminent correspondent Fabbroni, of-Florence, in which he says, “* a brilliant discovery has beem made by one of my friends. I have inclosed an account of it, which you will transmit to mv respectable and dear friend Kirwan, after having communicated it to the philosophers of your country through the medium of your journal.’”*” We there- fore gladly take this means, though somewhat irregular, of complying with his request, and of giving to our readers the earliest possible notice of the discovery alluded to. © Letter of Dr. Francis Paccutont, Professor of Philo- sophy in the University of Pisa, to LAURENCE PIGNOTTI, Historiographer to the King. “ To you, my much respected friend, both on account of the spontaneous impulse of innate kindness with which you deigned to take so much care of my talents, such as they are, as to receive me among the’number of your pupils, and on account of your having paved the way for my obtaining that very chair which was filled by you for many years with so much applause and honour to our country, rather than to any other person, shall I give an account of a discovery which I have made and satisfactorily verified. But these are not the only reasons by which my conduct 1s influenced. I wish, at the same time, to show my gratitude towards you, and to give you a proof that I am endeavouring to render myself more worthy of your esteem and friendship. << Tt is perfectly known to you that, since’ last year, on account of the premiums proposed by that excellent general and philosopher Bonaparte, emperor of the French, for the advancement of that new and fertile branch of experimental philosophy discovered by the celebrated professor of Bologna, Galvani, and afterwards wonderfully extended by the sub- lime genius of Volta, I have contrived a great number of experiments, which I have performed with much, care, and almost completed. These experiments have revealed to me many facts, which I am collecting for a memoir to be pre- - M2 sented 186 = Formation of muriatic Acid ly Galvanism. sented to the Societa Italiana; and have Jed me to a know= © ledge of the constituent elements of an acid which has bi- therto proved refractory to all the efforts of chemistry. I speak of the muriatic acid, bitherto tortured in vain * with the electric spark, caloric, and all the play of affinity. You are perfectly acquainted with the different and discordant opinions of the most recent and approved writers concern= ing the nature of this acid; some of them considering it as a simple combustible body, others as formed of an unknown base combined with oxygen; and, lastly, others as a simple substance naturally acid. But these opinions have not con- Rributed to the advancement of science, and are justly esteemed as mere hypotheses destitute of proof. «© Having, however, neglected these hypotheses, and considered the means by which the discovery of the nature of this acid has been hitherto attempted, it appeared to me that one had not yet been tried, viz. the continued action of the pile of the celebrated Volta, and I suspected that it might assist im leading me to discoveries which had hitherto escaped the research of experimental philosophers. As far as I can judge, my endeavours have been crowned with success, and have furnislred me with satisfactory evidence of the nature of the constituent principles of muriatic acid. * The simplicity of the apparatus, and of the means adopted to attain my views, the care with which I endea- voured to avoid every source of error, have, I hope, sufh- ciently secured me against those illusions which frequently deceive young men ardent in the pursuit of science, and even those practised in the art of extorting from nature her secrets. Want of time prevents me from relating the series of experiments by which I arrived at the discovery I have mentioned ; but you may sce it by perusing the manuscript of my memoir, which will be immediately published, to - submit my researches and their results to the judgment of the Jearned. For the present, I shall select from the expe- riments and facts therein described those which are decisive, and which establish, in an evident manner, the following truths : Bie ‘» coated with stucco. ; Near the town of Ficsole, not far from Florence, a beau- tiful amphitheatre has been also discovered. The earth has already been cleared away from the greater part of it, and it appears that it was capable of containing at least 30,000 spectators. _ VACCINATION. We hear that Dr. Jenner is engaged in collecting reports from the different states of Europe, and from many of the gther quarters of the globe, respecting the effects of vaccine inoculation on the mortality occasioned by the small-pox. In several of the largest cities on the continent, we are in- formed that he has already received the pleasing intelligence of the small-pox being either nearly or totally babe. Among them is Vienna. But how melancholy is the re- flection, that while the great aud populous city of Vienna, which for time immemorial had been subjected to the in- cessant 190 Palladium. —Astronomy.—List of Patents. cessant ravages of the small-pox, exhibited two deaths only by that disease in the year 1604, the city of London should even at this moment have to deplore the untimely fate of near fifty persons weekly by this horrid pestilence ! a pesti- lence which it is obvious, from this and other similar ex- amples, might not only be speedily banished from the me- tropolis, but from every part of the British empire. PALLADIUM. This new metal, recently discovered by Dr. Wollaston, may now be bought at Messrs. Knights’ warehouse for che- tical apparatus, Foster-lane, Cheapside, London. ASTRONOMY. A Table of the right Ascension and Declination of Ceres and Pallas. CERES. | PALuas. AR. Decl. N. AR. Decl. S. 1805 [ h m s ° , h m s ° fan | Sept.2| 6:39 52} 22 17] 4 39 12) 8 97 -5}6 24 8/|22 21] 4 42 48| 9 9 $16 28 90; 22 2] 4 46 16] 9 53} 11|}6 32 24}292 298]4 49 36)10 39 14|}6 36 24] 22 31] 4°52 48|31 26 1716 40 20/22 3444 55 52/12 15} 20|6 44 8{|22 38] 4 58 44/13 5} 2316 47 \48 | 29 40/1 & 10.84 [1H sTy 2616 SI 98/92 44] 5 3 56}14 50} 29|6 54° 56/22 4715 6 16/15 45} LIST OF PATENTS FOR NEW INVENTIONS. »! John Slater, of Liverpool, in the county palatine of Lan- caster, gentleman; for certain improvements upon sawing- mills, or machines for sawing all kinds of timber. Mare Isambard Bruncl, of Portsea, in the county of Hants, gentleman; for saws and machinery, upon an im- proved construction, for sawing timber in an easy and ex- peditious manner. John Edwards, of the parish of St. Paul, Covent Garden, in the country of Middlesex, currier and harness-maker ; for certain improyements on bridles. Obadiah Jliot; of the parish of St. Mary, Lambeth, in the county of Surrey, coach-maker ; for certain improve~ ments in the construction of coaches, chariots, barouches, landaus, and yarious other four-wheel carriages. Bat OAR List of Patents for New Inveniions. 191 John Edwards, of the parish of St. Paul; Covent Garden, 4n the county of Middlesex, currier and harness-maker; for a machine or apparatus upon an improved consiruction, for the purpose of preventing persons being drowned, which he denominates the life duoy. William Horrocks, of Stockport, in the county of Ches- ter, cotton manufacturer; for further improvements to a machine for the weaving of cotton and ether goods by hand, steam, water, or other power. Charles Hobson, of Sheffield, in the county of York, silver plater, Charles Sylvester, of the same place, chemist, and John Moorhouse, of Shefheld atoresmg, surgeon; for a method of sheathing ships, roofing houses, and lming water-spouts, with a material not heretofore used for those purposes, Thomas Pidgeon, of the parish of St. Pancras, inthe county ef Middlesex, gentleman ; for a saddle upon an im~- proved construction. - Abraham Ogier Stransbary, of the city of New York, in the United States; for locks and keys upon an improved construction. John Bevans, of Little Oucen-street, Lincola’s-inn Fields, in the county of Middiesex, carpenter and joiner; for a window-frame and sashes upon a principle wholly new, applicable to frames and sashes already made as to new ones, which conceal the sash-lines and exclude the air. John Blunt, of the borough of Warwick, m the county. of Warwick, surgeon ; for an improvement to stirrups now in use, which is to be fixed thereto, and by means of which, whenever the stirrup happens to be in a reversed direction, by a horseman falling from his horse, the stirrup will im- mediately fall from the leather, by which means the same is suspended. - ; Samuel Miller, of the parish of St. Pancras, in the county of Middlesex, engineer ; for an improvement upon, and ma- chinery to be attached to, coaches and various other car- riages, for the better accommodation of passengers. on Cox Stevens, of New York, North America, but now residing in New Bond-street, in the county of Mid- dlesex, gentleman ; for a new method of generating steam. Alexander Brodie, of Carey-street, in the liberty of the ros, and county of Middlesex, iron-master and tounder ; for an improved method of making steam-engine boilers and steam boilers, for vagious other purposes; and of con- structing the flue for the conveying the heat to the same, whereby the consumptian of fuel is considerably lessen: & ' METEOR 192 Meteorology. METEOROLOGICAL TABLE By Mr. ‘ Days of the Month. CAREY, OF THE STRAND, : For July 1805. Thermometer. ag ee ss : +f - | Height ro 2 s 8 * = tne eae 2 eae 5 Weather. 5 3 lou {| Inches. | Eo & 2 3 sex 65°} 53°} 29°80 17° |\Showery 56 | 51 “80 oO |Thunder ana hail showers 61 } 54 } 30°01 42 {Fair 70.| 57 “13 48 |Fair 69 | 61 “21 62 |Fair 68 | 60 | 29°98 32 |Cloudy 68 | 61 ‘80 15 |Rain 76 | 68 *63 60 |Fair 68 | 60 “60 42 |Cloudy 66 | 56 *71 45 |Showery 67 | 58 °88 29 |Showery 59 |} 56 °90 10 \Showery 68 | 58 | 30°00 37 «(|\Fair 71 | 56 | 29°90 58 |Fair 58 | 53 | 30°02 1g |Cloudy 64-1 55 ‘Ol 52 |Fair 66 | 56 | 29°98 52 |Fair 68 | 57 98 15 |Cloudy 61 | 56 "99 18 |Cloudy 66 | 57 | 30°03 5) |Fair 61 | 55 “08 29 |Cloudy' 64 | 53 ‘06 42 |Fair 64 | 58 "02 36 |Fair 74 | 62! 29°90 26 «|Fair 69 | 58 ‘68 6 |Showery 70 | 59 “73 42 |Fair, rain at night 70 | 60 “98 27 =|\Showery 66 | 59 65 40 {Fair 64 | 57 06 43 |Cloudy 70 | 58 | 30°01 46 {Fair “Ss N. B. The barometet’s height is taken at noon. ¢ [ 193 J XXIX. Account of Experiments made on a Mineral called Cerite, and on the particular Substance which it contains, and which has been considered as a new Metal. By M. VavauEtin*. : M. KiLaproTH wrote to me. about eight months ago, that he had discovered, in a mineral of Batsnaes, in Swe- den, a new earth to which he had given the name of ochroit, on account of the red colour which it assumes by calcina- tion. He even sent me in a letter a small specimen of this substance; and having discovered in it, by several trials, the presence of a considerable quantity of oxide of iron, I started some doubts, in a note which I read in the Insti- tute, in regard to the colour of that earth. I observed also in the same note, that this substance had as many metallic properties as earthy characters ; but that the small quantity of it which [ had in my possession did not allow me to give any decisive opinion on this subject f. Some time after, Messrs. Berzelius and Hisenger, having been informed, by their correspondents at Paris, of M. Klap- roth’s labour, wrote to me to claim a priority, stating that they had sent to M. Klaproth the specimens of that mineral which he had employed for his experiments, and that at the same time they had announced to him that they had found a new metal in it. I can give no opinion on this difference. I shall only observe, that the well known de- licacy of M. Klaproth, and the high reputation he has justly acquired by his numerous and important discoveries, render it very improbable that he would appropriate to himself the discovery of another. M. Klaproth must, no doubt, have received from another quarter the mineral in question; and his labour was perhaps terminated before he acquired any information respecting that of the Swedish chemists. What scems to justify this opinion is, that they obtained results entirely different. Every thing, therefore, seems to show that M. Klaproth of Berlin, and Messrs. Berzelius aud Hisenger of Stock~ holm, made experiments at the same time on the same mineral without having any communication with each ‘other; and that each may have had the honour of the dis- covery. The Swedish chemists transmitted to Paris a memoir on * From Annales du Muséum National @’ Histoire Naturelle, No.'30. t See Annales de Chimie, No. 149, Floreal 30,,an 12, Vol. 22. No. 87. August 1805, N this 194 Account of Experiments this subject written in Swedish. M. Limdbon undertook a translation of it, and caused it to be printed in the An- nales de Chimie*. In this memoir they give a history of the mineral, and point out the places where it is found, and the substances which accompany it: they then give an ac- count of the methods they employed to ascertain the na~ ture of it: they give the characters of the new substance it contains, and which they consider as a peculiar metal, to which they give the name of cerium; a denomination taken from the planet Ceres, discovered by M- Piazzi: they have thence formed that of cerite, to denote the natural ore of that metal. About the end of November, that year, I received, by the care of Messrs. Hisenger and Berzelius, specimens of this fossil; with an invitation to repeat their experiments, and to determine whether the substance in question ought to be classed with the earths or the metals. I charged my- self the more readily with this labour, as it furnished me with an opportunity of subjecting to experiment a new sub- stance, and of pronouncing in regard to the opinion of re- snectable philosophers, whose sole object is truth. It will be seen by this memoir that the force of facts has obliged me to adopt the opinion of the Swedish chemists. I must not omit to. mention that I have been seconded in my experiments by Messrs. Tassaert and Bergman, both of whom are well versed in practical chemistry. Physical Properties of Ceriée. This mineral is of a slight rose colour: it is sufficiently hard to scratch glass :. its specific gravity is 45°30, and its: dust is grayish: it becomes reddish by calcination, and loses: twelve percent. There are some varieties which contain martial pyrites,. and which are traversed by veins of green actinote. Preliminary Trials on Cerite- This mineral, when pulverized in a mortar of silex, does. not increase in weight, which indicates that its hardness is: not very great: its dust is of a rust gray colour. When exposed to heat in a retort there are obtained some drops of water, which are condensed. in the neck of the vessel. . The dust of cerite is powerfully attacked by the nitric smuriatic and nitro-muriatic acids; caloric is developed, and: ® No. 150, Prairial 30, an 12.. ‘ there: ee made on a@ Mineral called Cerite. 195 there is disengaged carbonic acid as well as nitrous gas when nitric acid is employed. After ebullition of half an hour the action of the acids appears to be exhausted, and there remains at the bottom of the vessel a dust more or less coloured, which is the silex contained in the mineral. When cerite is treated with eight or ten times its weight of acid it is entirely decomposed by one operation, and without the necessity of beginning a second time; yet it is impossible by these means to obtain silex perfectly pure : it always retains a certain quantity of metallic oxide. It is only by fusing this earth with an alkali, and then combining it with an acid, that it is possible to obtain it pure, and free from all colouring matter: it generally forms about seven- teen hundredths of the mineral. When the solutions of this matter are evaporated to dryness and the residuum is dissolyed in water, there is formed a slight white precipi- tate, which appears to be a little silex which the acid held in solution. Solutions of cerium are of a yellowish red colour, like that of the oxide of iron at its maximum ‘of oxygenation ; but when cerium is little oxidated they are only of a rose colour, similar to those of manganese and cobalt. These solutions, decomposed by ammonia, furnish a very voluminous precipitate, which has the appearance of alu- mine mixed with oxide of iron, but which greatly differs from it in its properties: when dried in a gentle heat this precipitate is reduced to a granulated powder of a pale yel- low colour, which becomes of a brick red by calcination. The matter simply dried in the air redissolves readily in the nitric and muriatic acids; but the red oxide, that which has not been calcined, is scarcely attacked, and does not dissolve in muriatic acid without producing a very consi- derable quantity of oxygenated muniatic acid. The nitric solution readily crystallizes : the salt which it furnishes is soluble in alcohol: in regard to the muriatic solution it is very difficult to obtain crystals: this salt when dried is deliquescent. m 4 The nitric and muriatic solutions are decomposed by al- kaline sulphates, phosphates, borates, oxalates, tartrites, and carbonates: with sulphates there are formed yellow pre- cipitates too soluble in water to be subjected to analytical experiments: besides, a part of the iron oxidated to a max- imum is precipitated at the same time. The precipitate formed by the borates is still more soluble in acids: that produced by oxalates is attended with the jnconvenience of Ne carrying 196 Account of Experiments cartying with it a little iron, which gives it a slight tint of a rose colour: it is soluble in acids. The tartrites form @ recipitate much less soluble, which does not contain iron; fer it is entirely soluble in caustic alkalies as well as in ar excess of its concentrated acid, from which it is afterwards separated by water. Phosphates occasion a precipitate which is not soluble in acids without the aid of heat: iron remains in intimate combination with it. Prussiates preci= pitate solutions of cerium white, even when they contain evi- dent traces of iron. All the precipitates here spoken of are white, and retain that colour after desiccation, except the phosphate, which becomes grayish. Sulphurets and hy- dro-sulphurets precipitate solutions of cerium white: the precipitates when washed retain their white colour in dry- ing, and dissolve invacids with effervescence : carbonic acid is disengaged, but not an atom of hydrogenated sulphuret ; which proves that cerium does not unite with sulphurized hydrogen. Zine, tin, and iron, immersed in a solution of muriate of cerium, do not effect a reduction of it. They precipitate a black matter, which is in too small quantity to be ana- lysed; there is deposited at the same time a white powder, which appears to be an oxide of the precipitating metal. An alcoholic solution-of gall-nuts produces in muriate of cerium a yellowish precipitate not very abundant. . The ad~ dition of a few drops of ammonia determines 2 very volu= | minous one of a brown colour, which becomes black and brilliant by desiccation : by the action of heat it resumes a beautiful brick red colour. When the silex extracted from cerite is fased with an alkali, it is observed that the mixture assumes a beautiful pale straw colour, which soon passes to brown: if the sur+ faces be often renewed the whole matter becomes brown, but by adding a little charcoal this colour vanishes entirely. Having made these preliminary trials on cerite, and ascer- tained’ the principal properties of the particular substance which it contains, I undertook to analyse it, in regard to quantity, in the following manner : A hundred parts of this mineral in fine powder were mixed with ten times their weight of nitro-muriatic acid, and subjected te ebullition for an hour: the mixture being diluted with water, and filtered, left on the filter a brow dust, which was dried, and fused with caustic potash. The’ mixture being diluted with water, and then dissolved in muriatic acid, evaporated to dryness, and redissolved in water, left a powder which when collected on a filter, - washed, made on a Mineral called Cerite. 197 washed, and calcined, weighed seventeen parts: it was silex, still slightly coloured yellow. The nitro-muriatic solution being evaporated to dryness, and its residuum redissolved in water, left about one part of silex coloured by a little oxide of cerium. The same solution freed from silex, and united to the washings of the silex, was decomposed by ammonia: the oxide of cerium and the oxide of iron precipitated by these means, were separated from the liquor by filtration. The oxalic acid added to this liquor formed a precipitate which by calcination gave two parts of lime. The metallic oxides, united and calcined, weighed seventy parts: they had a beautiful reddish brown colour. To se- parate the iron of the cerium the whole was dissolved in muriatic acid: the solution being concentrated to evaporate the excess of acid, then diluted with water and decomposed by tartrite of potash, there was formed a very abundant white precipitate, which being washed till it contained no more foreign salts, then dried, and calcined, gaye sixty- seven parts of oxide of cerium. The water from the washing of the tartrite of the cerium, being united and mixed with hydro-sulphuret of potash, gave a precipitate which became black in the air. It was oxide of iron, the weight of which after calcination was two arts. Thus 100 parts of cerite subjected to analysis furnished, jst, Silex ~ - 17 2d, Lime - - 2 3d, Oxide of iron - 2 Ath, Oxide of cerium - 67 Sth, Water and carbonic acid i2 eres 100 Though the specific gravity of cerite, the varied colours assumed by the particular matter it contains, and the oxy- gen disengaged during its solution in muriatic acid, afforded great probabilities in regard to the metallic nature of this substance ; yet, as it was possible that these properties and these phenomena might be owing to the presence of some known roctal, to manganese for example, I endeavoured to discover it by all the means which appeared to me proper for accomplishing that end; but I did not find any sensible traces of it. It therefore appears to me altogether ‘impro~ bable that manganese should contribute any thing towards the properties exhibited by the matter of cerite. The case N3 is 198 Account of Experiments is not the same with iron. I must confess that when any traces of it remain in the cerium it communicates to it a darker red colour; but as this matter, when disengaged from iron, as far as chemical means will allow, assumes still a reddish colour by calcination, and as in this state it furnishes as much oxygenated muriatic acid as before, it is equally impossible to ascribe these phenomena to the iron, which, as is well known, produces no oxygenated muriatic acid. Thus as cerium, in which the slightest sign of the pre- sence of iron, or of any other foreign matter, could not be detected by any means whatever, always assumes a red colour by calcination, and then gives oxygenated muriatic acid during its solution, I am forced to consider it as a metallic oxide rather than an earth, as M. Klaproth has done. Hitherto, indeed, chemists were not acquainted with any earth weighing five times as much as water, which has a colour of its own, which absorbs oxygen, and which, dissolving in common muriatic acid, praduces oxygenated muriatic acid. I had great hope that the reduction of this matter to the metallic state by the action of a strong heat would confirm the above probabilities, and convert them into certain truths 5 but this operation was not attended with all the success I expected. In the first attempt, in which I had put into a charcoal crucible oxalate of cerium reduced to a paste with oil, the whole was volatilized by the violence and duration of the heat: at the bottom of the crucible I found only a metallic grain scarcely so large as the head of a pin, and which was an alloy cf iron and cerium. This experiment, if it fur- nished no metal, proves at least that oxide of cerium is vo- Jatile ; and I do not know that an earthy substance was ever thus volatilized. In the second operation I put into a Juted porcelain retort a paste made with tartrite of cerium, a little lamp-black and oil, in order that I might collect the metal if it should be volatilized as before; but as the form of my apparatus did not permit me to give as much heat, the matter was not reduced: it remained in its natural state mixed with the charcoal. : There were seen, however, on the sides of the retort @ great number of small globules which bad metallic bril- jiancy, and the substance of which had been manifestly volatilized. Some of the largest of these globules havmg been detached and broken, exhibited in the inside a se colour made on a Mineral called Cerite. 199 colour and a foliaceous texture. There was also in the neck of the retort a slight reddish covering, the taste of which was exceedingly acrid and metallic: the quantity of the matter which formed this covering was too small to be sub- jected to experiments capable of determining its nature. Three of these small metallic globules, which weighed together scarcely a fourth part of a gram, being put suc- _cessively into nitric and muriatic acid, were not sensibly attacked: to effect the solution of them the union of these two acids was necessary. The solution being evaporated, and its residuum dissolved in water, had no colour ; its taste was sensibly saccharine; and by the oxalate of ammonia and the prussiate of potash it gave white and flaky precipi- tates. It appears, then, that these globules, which I sus- pected to be iron, are really cerium. What is certain is, that these globules are much more fragile, whiter, and less liable to be attacked by acids than cast iron. These experiments prove that cerium is volatile at a high temperature, and that it is probably only at the moment of its volatilization that it is reduced, unless we suppose that it is rather volatilized in the state of oxide. This I propose to ascertain by new trials. Recapitulating what has been said in the course of this notice, it is seen, Ist, That cerium, freed from the foreign matters which accompany it in the mineral, is a substance susceptible of uniting with two quantities of oxygen very distinct. ad, That with the first quantity it forms a white sub- stance, soluble in acids, without any disengagement of ox- gen. 3d, That with the second portion it assumes a slight red colour, combines only with difficulty with acids, and con- stantly produces a considerable quantity of oxygenated mu- siatic acid by dissolving in common muriatic acid. — 4th, That these oxides do not dissolve in alkalies; but that when boiled together they no longer become coloured by the contact of the air; and that those which are red be- come white by a slight heat, without, however, combining with the alkalis. 5th, That their combinations with the sulphuric, phos- phoric, oxalic, tartareous, and prussic acids are white, and insoluble in water. 6th, That, on the other hand, those which they form with nitric, miuriatic, and acetic acids are very solu le in water and in alcohol, and are even deliquescent. he N4 7th, Tha 200 On some zoological Facts 7th, That all these salts have an astringent and highly saccharine taste. 8th, That a good process for separating the iron of ce- rium is, to precipitate the latter from its nitric or muriatic¢ solution by oxalate of ammonia or tartrite of potash, put- ting into the liquor a slight excess of acid; or, what is better, is, to calcine the muriate of cerium, to redissolve its residuum in the muriatic acid, to calcine again, and to re- peat this three times, in order to sublime entirely the mu- riate of iron; which succeeds very. well. oth, That cerium does not unite with sulphurated hydro- gen, like the other metallic oxides. jOth, That it appears irreducible by those means which generally succeed with the most refractory oxides, but that it is volatile, and that it is probably at this moment that its reduction is effected. 11th, That if, contrary to every appearance, cerium is not a metal, it has, at any rate, much more analogy and relation with that class of bodies than with any other; and for these reasons we shall place it, with Messrs. Hisenger and Berzelius, in that class, till it has been proved that it is better fitted to any other kind of matters. 12th, In the last place, that by some lucky chance, or means better combined than those hitherto employed, we shall obtain it in the metallic state; and 1 do not despair myself of meeting with this success. ee ey XXX. Memoir on some xoological Facts applicable to the Theory of the Earth. Read in the Physical and Mathe- matical Class of the French National Institute on the 22d of October 1804. By M. Peron, Naturalist to the Ex- pedition for making Discoveries in Australasia. [Concluded from p. 166.] T ave now terminated the general history of petrified and living zoophytes: we have seen them cantoned, as we say, jn that zone of the globe comprehended between the 34th degree of north and south latitude, where they fill the sea with dangerous reefs, form new islands, enlarge the old ones, and every where increase the domain of the land at the expense of the ocean which nourishes them in its bo- som: we have seen their antient labours rising over the sur- face of the waves, and appearing again at great heights above ‘their present level. The last phenomenon deserves our at~ ; tention applicatle to the Theory of the Earth. 201 oe tention for a moment; and two questions here present themselves to be resolved. Have the madreporic moun- tains been formed in the bosom of the sea? and, supposing this to be the case, what revolutions were capable of effect- ing so prodigious a change, either in their antient state or in that of the waves? There can be no doubt that the former of these questions may, and ought to be, answered in the affirmative. Ob- servation,—indeed experience, reasoning, and analogy, all unite to prove that. these pelagian animals, the vast remains _ of which cover our continents with an organization similar to that of families now existing, have had the same origin and the same country. No objection has yet been made against this general assent.’ But if any doubts of this kind had been formed in regard to the different banks of testacea, or even of zoophytes, disseminated throughout the large continents at considerable distances from the sea shore, the consequences could not be extended to those reefs, those islands, and those archipelagoes, several of which still de- clare their origin by the little elevation they have acquired above the place where they were formed. It may therefore be considered as an incontestable fact, that all the madre- poric productions we have seen raised more or less above the present level of the sea, were formed in its bosom. The second question, it appears, may be resolved with as little difficulty. I shall here observe, to make use of an expression of the Nestor of the French navy in regard to the enormous bones seen at the Malouines at.a considerable distance in the interior,—the land has either Leen raised up, or the sea has sunk down. In the first supposition, we can- not conceive any other cause susceptible of raising up si- milar masses, but volcanic eruptions as frequent as energetic. But independently of a multitude of other reasons which tend to make us reject a cause of this kind, do we not know that these grand convulsions of nature always leave behind them indelible traces of the disorder and confusion by which they are exclusively characterized? But nothing of this kind is observed in the madreporic countries. I have already spoken of the regular forms and insensible gradations of the island of Timor, an image and production at the same time of the calmness of nature: J have already quoted the ingenious observations of captain Vancouver, which alone are sufficient to show how peaceable was the cause which Jeft these madreporic eminences uncovered, whether its action was slow, rapid, or even instantaneous. Labillar- diere made similar observations: the two Forsters have fur- i nished . 202 On some xoological Facts nished us with valuable facts on the same subject: and M. Fleurieu himself, having given the opinion of these two naturalists, expresses himself as follows :—‘* To which of our common systems can we refer the origin of that pro- digious number of small spots, either scattered or formed into groupes, or united into archipelagoes, which, accord- ing to the most accurate researches, appear to be still in a state of increase? These islands are met with at the di- stance of 1500 leagues from the continent and from large islands, and in the middle of a sea the depth of which can~ not be measured with the sounding-line. The attentive eye of the enlightened observer has discovered nothing in these Jow islands which indicates the former existence, re- mains, or traces of burnt-out voleanoes, or volcanoes swal- lowed up by the sea; nothing which can show that they were produced by any convulsion of the globe: every thing, on the contrary, announces that they have been the production of ages; that the work is not yet completed; and that a gradual increase in them 'must take place: but that a long succession of years is necessary to render it sensible.” The unanimous opinion, therefore, of all observers, while it re- jects every idea of volcanic origin, destroys thereby every ether opinion which might suppose that the earth itself could rise above the surface of the waves. This immediate consequence then results, that the water must have sunk down below its antient level. A very delicate but interesting question here occurs: What became ef the water of the sea when it abandoned the summits of the mountains formed in its bosom? The solution of this question appears to me to have an imme- ‘ diate dependence on another of the same nature, and no less difficult :—Whence arises that enormous quantity of calcareous matter, which, as we see, performs so extensive a part in the revolutions of the earth? Here, also, an im- mense field is opened to imagination and hypothesis. Sa- tisfied myself with having collected, compared, and ar- ranged the most correct observations, that I might deduce from them the most general and most certain consequences, I shall give, in a few words, those which I conceive to re- sult from the numerous facts here stated. ist, From the absolute difference of the two races in Wew Holland and Van Diemen’s Land, as well as from the absence of the dog in the latter, | think myself authorized to conclude that the separation of these two countries must have taken place at a period much more remote than may- at first be supposed. od, The applicable to the Theory of the Earth. 203 ed, The exclusion of all relation betweea these two races ; the darker colour of the inhabitants of Var Diemen’s Land ; their short, woolly, and curled hair, in a country much colder than New Holland, where the contrary is the case ; appear to me to be new proofs of the imyerfection of our systems in regard to the mtercourse of natons, their trans- migrations, and the influence of climate 01 man. 3d, From the petrified shells and zoophytes which T ob- served in different places and at differen’ heights in Van Diemen’s Land, New Holland, and Timor I infer that the sea formerly covered that part of the Ausral lands which reaches from the 44th degree of south lattude to the gth, over an extent of 700 leagues from south tcnorth: a result the more valuable, as this immense region vas the only one which remained to be known under this pont of view. 4th, Having given this explanation as sinple as satisfac~ tory in regard to the formation of those beaitiful calcareous incrustations so frequent on the south-westand north-west coasts of New Holland, I have taken an opportunity of proving how difficult it is, in certain cases, to distinguish bodies altered in this manner from those yhich are really fossils. 5th, In my observations on solid zoophyes I have con- firmed their almost absolute exclusion from tle most Austral seas of the Antarctic hemisphere; I have poved that this important family of animals is banished bynature to the middle of the warmest seas, to the most deaceful equi- noctial regions, and those which border on trem. 6th, We saw them there, in the state ot petrifactions, forming all the low islands of the great equnoctial ocean, and some, at least, of the highest in thatsea and in the Indian Ocean. | 7th, We found them there, in the livin; state, inter- spersing the sea with new dangers, multipling the reefs, enlarging the islands and archipelagoes, enambering the harbours and ports, and every where throwin; up new cal- careous mountains. While man, therefore, who styles himsel the king of nature, years, with labour, on the surface of tle earth those frail monuments of his pride, which the brath of time must soon destroy; feeble animals, which lave so long escaped his observation, and which he still didains to no- tice, multiply at the bottom of the ocean thse immense testimonies gf power which brave ages, anl which our imagination itself can hardly conceive. XX XI. Letter = XXXI. Letter 0 M. Lacrrene, of Paris, on the Natural History of North America. . By Bunsamin Smite Barton, M.D. Professor of Materia Medica, Natural History, and Botany, in the University of Pennsylvania. [Concluded from p- 103.] Orr country, as you know, is very rich in birds. A considerable nunber of these have been described, or men- tioned, by Bufbn, Pennant, and other writers. But the arnithology of he North American continent is very im- perfectly underitood. Many of our birds have never been correctly, if atall, described. Some of these undescribed species-are large birds; such as a species of plotus, called in Carolina the snake-bird ; not to mention others. But it js a matter of more consequence to study the manners of those birds tha have already been discovered, than merely to detect new :pecies. I flatter myself that I have made considerable pogress in the study of the mores of our birds. I have been particularly attentive to their instincts as we call them, an: have even digested my collection of facts on this subject isto order. These facts will form a part of a Jarge work onthe Instinct of Animals. It is now com- pletely ascertined that some of the American species of swallows renain among us in a torpid state. They retire’ into the crevces of rocks, into the hollows of trees, and other similar situations, and rest, for some months, in a lethargic slep more or les’ profound. The species con- cerning whia I have the most correct information, as to what regardstheir torpidity, are the purple martin (hirundo purpurea), ad the chimney-bird (hirundo pelasgia). Both of these speies, I repeat it, do sometimes become torpid in the climte of Pennsylvania. It is probable that the other speciesdo the same. But I still adhere to my former opinion: I ontend that the great body of American swal- lows, of difkrent species, are really migratory birds; that is, they leae the climates of the United States on the coming on ‘f cold weather, and retire southward, to more favourable Ititudes. These facts show us how much birds ean accomnodate themselves to different situations, and give weightto an opinion which I have long entertained, that all aninals are capable of the torpid condition. Even the little hmming-bird (trochilus colubris), which is un- questionabl a (generally) migratory bird, is sometimes overtaken ly the colds of our climate, and, on such occa- sions, has ieen known to fall into the torpid state. I lately eee On the Natural History of North America, 205 T lately ascertained a fact in ornithology, at once singular ind interesting. It is well known that the anas sponsa of Linneus, called in the United States summer duck, breeds im the holiows of trees, on the banks of rivers, or in islands at a considerable height from the ground. The young ones, soon after they are hatched, descend the sides of the tree, and thus make their way into the water. 1 do not know of a similar fact in the history of birds. Thave read, with much pleasure, count Morozzo’s letter to you respecting a parrot hatched at Rome*. I am sorry, however, to find so sensible a writer adhering to the para- dox, that ‘the parrots both of the old and new continent fever pass the tropics, and seem confined to a zone of 23° on each side of the equator; and that ‘in their wild state they never pass these limits, which hature seems to have prescribed to them.” ‘The parrots of America are, I assure you, much greater voyagers than count Morozzo-supposes. They sail far beyond the tropics. They are frequently found in immense flocks upon the river Ohio as high as the Sati- _tude of 40°: nay, a very large flight of these birds has been seen, on the eastern side of the United States, as high as the latitude of 42°. From the birds T pass to the oviparous quadrupeds and other amphibia. The American animals of this class have been very imperfectly investigated. Notwithstanding your labours in your inestimable work on the Quadrupedes Ovi- pares, and the labours of Schoepf, we possess several spe- cies of testudo which have entirely escaped your attention. In the western parts of Pennsylvania, Virginia, &c. there is a species of this genus considerably allied to, but still different from, the one which you have called da molle. The new species is called by some of our Indians pi-si-li-Tul-pe, which literally signifies © the soft-shelled turtle.” They are very prolific, and both their flesh and eggs are deemed excellent eating. Our western rivers, such as the Ohio and its branches, likewise possess a very remarkable undescribed species of Jacerta, if, indeed, it be not entirely a new genus. It is sometimes seen near twenty inches in length. By the white people it is cailed alligator, though it is very different from the southern animal of this name. Its whole body, but in particular the head, contains a milk-like fluid. This animal lives upon fish, frogs, &c. It is often taken with the line and hook. The Indians say it is poisonous: but ® See Philosophical Magazine, vol. xvi. p. 318. _? See my Fragments of the Natural History of Pennsylvania, part ie, this, 206 On the Natural History of North America. this is a doubtful point. Several of our species of rana are entirely undescribed by naturalists.. I may, with great con- fidence, make the same observation concerning our ser- pents. The little black ratilesmake, which inhabits the marshy grounds, is, J think, a new species. This species is seldom more than a foot in length, and is deemed ex- tremely venomous. I suspect the species described by Mr. de Beauvois (in the Transactions of our Society), and which he calls crotalus adamantinus, is the same as that which is found in South America. I think it is not quite certain that the crotalus horridus, the most common species of North American rattlesnake, extends to South America. But I do not wish to be understood as speaking positively on this subject. The history of the rattlesnake is by no means complete. I have, within the last two years, devoted a great deal of attention to this curious subject. I have had a number of living rattlesnakes under my immediate care. I have made aconsiderable number of experiments to ascertain the ef- fects of the venom of this reptile upon different animals. It is unquestionably a most powerful poison. It often kills in a very few minutes. The effects of the poison are very various, not only in different species of animals, but even in different individuals of the same species. It:sometimes induces most violent pains, which, if we may judge from the cries of the bitten animal, continue nearly to the close of its life. At other times, the poison induces death with- out creating any or but very little pain. Hitherto my prin- cipal experiments have been made with warm-blooded ani- mals, such as dogs, cats, and rabbits. I am inclined to think that the venom exerts very inconsiderable effects upon cold-blooded animals. 'Warm-blooded animals that have been most violently affected by the poison, sometimes strug- gle through the danger, and perfectly recover, although no remedy has been applied. This may serve to show how many inert vegetables have acquired the reputation of curing the bite of the rattlesnake. I have ventured to apply a por- tion of the undiluted venom of a rattlesnake, recently thrown from its fang, to my tongue. I made this experi- ment in the presence of several gentlemen. But J do not think [ shall venture to repeat the experiment. I did not find the venom insipid, as the abbé Fontana and his servant did the venom of the viper. It had, on the contrary, a peculiarly pungent taste, and left, for a considerable time, a pretty strong sense of heat upon my tongue and fauces. My observations haye extended to eyery thing that yaight 7 _« ten On the Natural History of North America. 207 tend to illustrate the history of this wonderful reptile. I have found that its powers of digestion are very strong. Even the bony fabric of the animals which it devours is completely digested, or reduced to the state of a fluid mortar. This I have several times observed. Great, however, as is the faculty of digestion in this reptile, it is capable of living a very long time without any food, unless, perhaps, a smalt quantity of water. One of my rattlesnakes lived, without having ate one grain of any solid food, from the 28th of April to about the 9th of March following. It then died; but upon examining it J found it very fat. I have now two of these reptiles in my possession. One of them has eaten nothing since the middle of October last. The rattlesnake sheds its skin at least ence every year. During the twe summers that I have been making observations upon these animals, the old ones have shed their skins only once each year, viz. about the end of July. A young one, however, shed its skin twice in the course of the year, and that with- in five weeks. A rattle, or bell, is formed with each cast- ing of the skin. It appears, therefore, that the full grown reptile generally acquires one bell annually. But I have elsewhere shown * that we cannot, with confidence, calculate the age of the animal from the number of its bells. I have, after much inquiry, ascertained the period at which these Teptiles copulate. The Indians are my authorities. They assert that it is when the Indian corn (zea mays) is in flower; that.is, about the 10th or 15th of July, between the latitudes of 39° and 41°. IT have had a number of very fine drawirigs made to repre- sent the anatomical structure of the crotalus. These draw- ings it is my intention to have engraved, by some of the best of your artists, for my Anatomy and Physiology of the Rat- tlesnake; a work which I hope to publish in three or four years. It will contain every thing I have observed, or have been able to collect, relative to the structure, the functions, the manners, &c. of the crotalus horridus; together with observations on some other species of the same genus, and on various species of coluber, &c. all natives of the United States. Perhaps no country of equal extent is richer in insects than the United States. In no country is it an object of more importance to attend to the history of these animals ; _ for among them are enlisted some of the greatest enemies - ‘to the labours and industry of man. The heats of our cli- * Supplement to a Memoir, &c. mates we 208 On the Natural History of North America. mates are extremely favourable to the generation and itt- crease of insects: our colds are not sufficient to destroy them. We do not cultivate one important vegetable that is not exposed to the devastations of some highly injurious species of insect. Our wheat, you know, has for many years greatly suffered by a species of tipula, called by us the Hessian fly. This, at present, is much Jess formidable in its ravages than it has been. The curculio, or weavil, which it is highly probable we received from Europe, is still very destructive in the southern parts of the United States. A species of cimex, not, I think, described, as- sists other insects in destroying the finest of all the cerealia ; I mean the zea mays, or Indian corn. Partly owing to the ravages of insects, it is to be feared that, in the course of a very few years, there will be a great scarcity of that fine fruit the peach in our country*. [could mention a hun- dred other insects of the most pernicious kinds. It is a melancholy fact, that the industry of my countrymen has been much moré exerted in destroying the insects which infest one of the vilest of plants, I mean the tobacco, than in endeavouring to stop the ravages of any of those species which lay waste the most useful of our crops! You must not, however, suppose, from what I have said, that the study of entomology is entirely neglected in the United States. On the contrary, this very important branch of natural history (for such, when it is properly cultivated, it unquestionably is,) has several votaries, some of them ar- dent votaries, in our country. The principal of these is the reverend Mr. Valentine Melscheimer, a clergyman, who employs a portion of his time in the cultivation of this sci- ence, which has always been deemed favourable to religion. This gentleman has discovered several hundred new species of American insects, a catalogue and description of which may, perhaps, be published. I must still regret, however, that it is chiefly the nomenclature of the North American insects that is attended to. Other more important parts of their natural history are too much neglected. Some pros gress, however, has already been made in discovering re- medies against the ills which result from these animals. Moreover the useful properties of several other species have been discovered. Various species of the genus lytta of Fa- bricius inhabit our country. The lytta vittata of this en- * The unripe fruit of the peach is greatly injured by a species of curculio; but the insects most pernicious to this tree are two lepidopterous insects, of the genus zygeena of Fabricius. These, while in the larva state, destroy the bark of the root. tomologist > On the Natural History of North America. 209 tomologist is called potatoe-fly, because it abounds upon the stems and leaves of the solanum tuberosum, or potatoe. . It inhabits various other species of vegetables ; such as the flax (dinum), the beet (leia), black snake-root (uctea ra- cemosa), &c. This insect has been found to be a very effi- cacious substitute for the cantharides of the shops, and is now employed, with this view, by many of our physicians. I shall conclude this part of my letter by observing, that I still continue my inquiries into the natural history of the North American tribes. On this subject I have read before our Philosophical Society a discourse, which it is my inten- tion to publish in a much more enlarged and perfect shape. Since the publication of my New Views, I have made great progress in collecting and comparing the languages of the American tribes with one another, and with the languages of Europe and Asia. Every step I take only serves to con- firm me in my former opinion, that the (known) radical languages of North America are very few in number, and that all the Americans are of Asiatic origin. I have lately received from Mexico an inestimable treasure,—a collection of a number of vocabularies of the old Mexican dialects. Between these and the dialects of Asia I find great affinities, - sufficient to convince me that the Mexican nations (con- trary to the paradox of Camper) are not of European ori- gin; much more than sufficient to excite in me the greatest surprise that the learned abbé Clarigero, after leisurely comparing the Mexican languages with those of the old world, should have found no affinity between them. The afinities, I repeat it, are very great. OF all the branches of natural history, none, I think, is so little cultivated in the United States as mineralogy. This is the more remarkable, not merely by reason of the great utility of this branch of the science, but because its sister science, I mean chemistry, is ardently cultivated in dif- ferent parts of the country, particularly in Philadelphia. Mineralogy, however, is not entirely neglected in the United States. It possesses, among other votaries, an ingenious cultivator in Dr. Adam Seybert, to whom we are indebted for the discovery of a mineral which is supposed to be co- rundum or adamantine spar. This is found to be abundant in the neighbourhood of Philadelphia. -Mineralogy arid chemistry, and [ may add the other branches of natural history, have lately sustained a loss, not perhaps easily to be repaired, in the death of Mr. Thomas P. Smith, a young man of the most capacious mind, and of the warmest en- thusiasm for the attainment and promotion of science. Vol. 22, No. 87, August 1805. O ~ Mines 210 On the Natural History of North America. Mines of various kinds are very abundant in the United States. We are extremely rich in iron, copper, and lead. The iron mines of Pennsylvania are, perhaps, inexhaustible. Prodigious quantities of copper, nearly in a native state, have been discovered near Lake Superior. A bed of cin- nabar has been discovered in Virginia; and several veins of plumbago have been detected in Pennsylvania and other parts of the Union. As to gold and silver, these, as-yet, are principally to be found in the fields that are cultivated by the virtuous hand of agriculture. Our country is ex- tremely rich in coal. This useful article has hitherto been found in the greatest abundance in the western parts of the United States, beyond the Alleghaney mountains. It is in this same part of the continent that the principal salt springs, ’ and mines of sal-gem or rock-salt, are found. In a few years we shall, in all probability, be able to do without the salt of Europe. Hitherto very little sal-gem has been detected within the limits of the United States. I am not, indeed, certain that any has been detected. It must, however, abound at no great distance from the immense salt springs, which are now found in so many parts of our country. Of sal-gem, however, prodigious quantities have been disco- vered in the country that 1s watered by some of the branches of the Missouri, west of the Mississippi *. I have lately returned from a three months tour (which had been principally undertaken for the recovery of my ’ health) through the western parts of Virginia. I have visited many of the most interesting natural objects in that part of the United States, and have brought home a very considera- ble collection of vegetables. Jn travelling over some of the principal ranges of our mountains, particularly the Blue Ridge and the North Mountain, I have not observed that any of them are purely granitical. The stone composing these mountains is, indeed, various; but I think the pre- dominant species is a petro-silex, of different degrees of. hardness. Veins of schistus are sometimes found upon some parts of these mountains$ but such veins are princi- pally abundant about their bases. I have paid particular attention to the declivities of the mountains. These I find to be much less regular than Mr. Kirwan’s ingenious ob- servations (concerning mountains in general) would lead us * Since writing the above, I have learned that very large quantities of sul- phate of magnesia, or Epsom salt, have been discovered in some of the cal- careous caves in the western parts of Virginia. It is also said that the borate of soda, or common borax, has been found in others of these caves. But this last report requires further confirmation. to On the Natural History of North America. 211 to suppose. The general range of these American moun- tains is north-east and south-west. In some places the north-west and in others the south-east sides are the steepest. The valley which is comprehended between the North Mountains and the Blue Ridge is principally calca- reous, Very generally the veins of limestone run parallel with the mountains, that is, north-east and south-west. When the nearest mountain varies from this direction, I observed that the adjacent strata in the valley do the same. These strata are sometimes perpendicular in their position, but never horizontal. It is remarkable, however, that most of the strata in the country west of the great Alleghaney mountains (which are to the west of the North Mountains) are arranged horizontally. This observation applies to the strata of limestone, schistus, freestone, and even to the stone coal and iron ore. This difference in the disposition of the strata east and west of the Alleghaney mountains is well entitled to the attention of naturalists. I have made it the subject of an express memoir. It has long been conjectured that the calcareous valley which I have mentioned was once an arm: of the ocean. This opinion has been maintained by Mr. Jefferson in his Notes on the State of Virginia. I entertain no doubt as to the antient covering of this valley by the sea, especially since my late researches have convinced me that the calca- reous strata abound with marine exuviz of various kinds. It is a circumstance very remarkable, that marine vestiges are much less abundant in the calcareous strata that are nearest to the present ocean, than in those which are at a much greater distance from it. Thus, although immense quarries of marble have been opened in the neighbourhood of Philadelphia, I have never yet been able to discover, though I have for several years been in search of them, the most distant semblance of a shell, or any thing of the kind, in hundreds of masses of this marble that I have exa- mined. I do not, however, assert that such vestiges do not exist in the eastern Pennsylvania marble. This very long letter was written principally for the amusement of my learned friend, who, following the foot- » steps of the immortal French Pliny, cannot but be interested in hearing any thing that relates to the progress of the great science of natural history. The letter is at your free dis- posal. Iam, with very great respect, my dear sir, Your friend and humble servant, &c. To M. Lacepede. BENJAMIN SMITH BarTON. Philadelphia, October 31, 1802. Oe XXXII. On XXXII. On feeding Cattle with green Food; together with other ingenious and valuable Observations in Agri- culture. By Mr. Epwarp Powys*. I conceive the principal. object respecting agriculture in the present state of this country, is to procure the greatest possible supply of the necessaries of life within the kingdom itself, and one principal means of doing this 1s, Lo raise the ereatest produce from a given quantity of land, To effect this, every encouragement should be given by land-owners to the cultivation of grain and turnips; be- cause I look upon the produce of an acre of grain to be, to the produce of an acre of grass, in the proportion of at least fifteen to two, in furnishing the necessaries of life. I sup- pose the grain made into bread, and the grass digested by a feeding beast, and changed into an increase of weight. One great means of increasing the growth of grain and turnips, [ think, would be to encourage the farmer to make as much manure as possible. This would be effected by allowing him to sell all his wheat and rye straw, with the restriction of laying out the whole price in manure; and by gentlemen, who have land in their hands, trying the expe- riment of keeping their cattle and horses in the house upon green food great part of the summer. For these last six years I have sold all the wheat straw I did not want for thatching and the beds of certain kinds of horses, and can assure you that the same farm has pro- duced for some years back one-third more grain, and keeps double the live stock it did six years ago. As a proof that what I say of keeping cattle in the house in summer upon green food is not matter of theory oniy, but of practice, I shall mention my own experience. For these last five years I have kept eight or ten wag- gon horses in the stable upon clover, cut and carried for them once a day; the small waste that they made was thrown into a low cratch (or receptacle, with staves on each side) for my pigs, which have generally been from 25 to 40. My horses and pigs, thus fed, have eaten, between the beginning of May and corn harvest, from 24 to 34 acres, according to the goodness of the clover. My horses have been, by this means, in much better condition than if turned into a field; there has been a saving of at least eight or ten acres of clover for other stock; a great deal of the richest * From General View of the Agriculture af Shropshire. ; manure On feeding Catile with green Food. 213 manure has been made (much more, and richer, than in the same time in winter), and the additional daily expense has been, one man less than half his time, in cutting, raking, and carrying with a horse and cart, one load each day. Ex ‘periment . . Dr. fi. 5 d. Cr. LEONG 6 One man half a day for 13 Fight acres of clover saved weeks, at 4s. per week 212 O by this experiment, at One horse 13 weeks, at 6s. 318 O 50s. per acre - 20 0 0 Manure, at least, - 1010 O 6 10 G6 Profit - - - 2400 30 10 O 30 10 O The first year I tried the experiment the manure made was estimated by a good farmer at 20l.; but I wish to make allowance for the value of the straw, and the manure that would have been made by the horses standing in the stable the usual hours in summer. I must endeavour to remove an objection that may per- haps be made to this experiment, by observing, that I can- not think Jand injured any more by the green food being eut by the scythe, than by cattle or horses ; and as to the dung that is dropped in summer, it breeds ‘Hies, and does more harm than ¢ good. T have ever thought land exhausted infinitely more by its produce being suffered to ripen and seed, than by its being cut in a green state. The advan- tage ] had derived from this experiment, induced me last summer to try whether cattle might not be treated in sp same way. I began with putting into stalls 19; I afterwards abe my stock fed in this manner to 50, consisting of horses, feeding cattle, milking cows and colts, besides a Tage quan- tity of pigs. The horses, as usual, answered well. The feeding cattle came on much faster than I ever saw them in summer. The milking cows fed very much, and _milked very well. The colts did well, and lived chiefly upon the refuse of the cattle. The pigs, as usual, ate the refuse of the horses. The quantity of land run over with the scythe for hia purpose was: Fourteen acres of trefoil, very moderate, on account of the clover root having died in winter. Two acres of vetches, very moderate, on account of the severe winter, Five acres of very good grass. QO3 The 214 On feeding Cattle with green Food. The cattle were turned out late at night for about six or seven hours. The trefoil caused some trouble, on account of the cattle sometimes swelling, but brought them on very well, though they throve best upon the winter vetch or tares, and upon the grass. The daily expense was one old man of more than 70, to feed and clean them, another young man to cut, rake, and carry the food with a single horse cart. If this stock had been turned out I should suppose they would have run over at least 60 acres, if the crop had been goods, and much more, if the indifferent trefoil is consi-: ered. Experiment. Dr. , Seas Cr. fare a: Two men 13 weeks, at 14s. 9 2 O Twenty-nine acres saved, One horseditto - me, * 41-0 at 50s. - - 97 10 Q, bis Jat hs peas 6) Profit - RE 83 17° 0 97 20) -O 9710 0 Any person that intends to practise this method should begin to cut his green food so early in spring that he may be able again to mow the same ground from hay to corn harvest. I have before observed, that I never saw cattle in summer come on so fast. I speak this, not only from my own ob- servation, but from that also of seyeral farmers and but- chers, who came through curiosity or business frequently to visit them. The’ most feeding green food is winter vetches ; and the most advantageous mode of cultivating them, I think, is to plough up a clean stubble (that is in- tended for turnips), manure it, and sow it with” vetches soon after corn harvest, When the vetches are all cut in May and June, or rather in the latter month, the field may be ploughed and sown with turnips for a winter crop. From corn harvest till September 22, my cattle were all out in the fields at grass. I then took up thirty into stalls, and fed them with turnips which had been sown early in May, and which had arrived at a very good size. My first field of turnips has been carried off, ploughed and sown with wheat, which has been above the ground some time, and looks very promising. I have practised this scheme of. sowing turnips in May, carrying them off before the beginning or end of the fol- lowing November, and then sowing the piece with wheat, for these last three years, And Ihave found this wheat 7 ~ much On feeding Cattle with green Food. 215 much more productive than any sown after any other crop or fallow. I am speaking of dry sown land. One year I got up all.the turnips of a field, topped and butted them (throwing the tops and butts in heaps by them- selves), carried the tops immediately as they were cut to a bare stubble for my cattle and sheep, and laid the butts up in large heaps either under cover or in my stack-yard, with straw over them. Where there was no straw in layers be- tween them, they kept for two or three months; some that had layers of straw every foot or half yard perpendicular, soon began to decay near the straw, which was made to heat by the moisture from the turnips. : From these experiments upon turnips, and from observ- ing that dry land of my own, though it produced crops of grain or turnips for many years together, with the change of clover (mown twice in the same year) only once in five years, did not lose any of its power, I have conceived that much more grain might be produced upon well cultivated farms. Wet land that is well cultivated might bear, in regular succession, crops of turnips, wheat, and barley or oats. Dry sound land may also bear the same succession when an early crop of turnips is wanted ; and when turnips are wanted to stand the winter, a succession of turnips, barley, and wheat. I think it is much more advantageous to carry all the turnips to cattle in stalls (except a very few left for sheep) than to eat them on the land, because they furnish much more food and manure. I am aware that many gentlemen of landed property will object to this constant tillage: in answer to which I shall only observe, that it has been my opinion and practice never to have any grass land that is not worth 40s. an acre; never to plough my grass land,, but to till the rest constantly, with the intermission now and then of turnips and clover, the latter only for one year. The farm I have above alluded to is about 240 acres, of which I have in grass land about 90 acres; in tillage for grain and turnips about 120 acres. The rest is ‘generally clover, unless I have a single fallow for wheat upon a field of wet land. I repeat it once more, that the interests of the public, of the landlord, and tenant, (for I know of no distinction when many years are taken into consideration) are united in the hire produce of the necessaries of life ; and that if arable and is kept clean and full of manure, it receives no injury from producing the greatest quantity of grain. The in- O4 creased 216 On feeding Cattle with green Food. creased produce of Jand benefits the public in too obvious 4 manner to enlarge upon. It benefits the landlord, by his being able, at the « expiration of certain fair intervals, to raise the rent of his farm; and the tenant or occupier, by getting more profit from a given 1 quantity of Jand, and with nearly a given capital. ‘I have recommended turnips once in three years, because I think Jand requires cleaning once in that time, and be-— cause it is thus effected without Josing the benefit of a crop in any year. Much has heen lately said about the superior advantage of cattle over horses in farmers’ teams. I think some horses must be kept for the farmer to take his grain to market, and to carry his coal and lime. If he is so near a large town that he can draw at least two load of dung in a day, he will also want them for that purpose. Other team-work may very well be done by cattle. But I think cows are much more useful and Beneneial than oxen, and that it would be an advantage to the kingdom if few or no oxen were reared. The uses of cattle are to work, milk, and feed. I have seen barren cows work as well as oxen; they require less keep, and walk faster. Oxen are of no use to the dairy, and they will not feed so fast as cows. When first I commenced farmer I followed the example of my predecessor, in feeding chiefly oxen; but I soon found that cows fed much faster and on less meat, and for some years past have carefully avoided haying any oxen in my stalls. J Meadows. i It should be considered as a great object of every Jand~- lord, or his steward, to procure watered or flooded mea- Bo 3 f - The best means of doing this is, to place the farm-+yard on such an eminence of the farm that a stream can be pro- cured to run through it, and afterwards over the greatest quantity of meadow ‘ind: ~ Common meadows ought to be well manured once in three years, and will then produce one ton and a half of hay per acre, and a pasture from the middle of September to Christmas. Good watered meadows will bear to be grazed from the beginning or middle of August till May following, and will, between that time and hay harvest, produce ae -fourth of hay more than the other, The —— On feeding Cattle with green Food. 217 The difference of the profit of watered meadows over common, I think, is annually as underneath : One-third of 51. (the expense of manuring an acre of land) ab, ASS = - 1. Aso One-half ton of hay additional - 121 ,5ia@ Difference of the value of grazing - OF. VReLs oe BiB: 30 But besides the produce and profit, there are two other “yery great advantages in watered meadows. The one, saving manure for arable land, the other keeping the pastures free from stock the beginning of spring. I have hitherto only mentioned a stream that runs through a farm-yard, but I have frequently observed very great ad- vantages derived from nothing but clear spring water being turned over grass land. If a farmer has a greater command of water than he wants for his meadows and pasture land, he may occasion- ally till some of them for two or three years, and they will produce great crops without manure. I saw this practised with great success, this last summer, by the late Mr. Bake- © well, of Dishley, Leicestershire. Size of Farms. Much has been lately said upon the size of farms, from the high price of grain being supposed to arise from the opulence of the farmer, and his being able’ to keep back his grain from the market. I might combat this assertion by the well known fact, that at the harvest of 1794 there was not a fortnight’s consumption of wheat in the king- dom, and yet the price was moderate. I might also add, that there never was so much wheat brought to market be- fore Christmas as has been for these last two years, and that it has only been when wheat was plentiful that any of the stock remained in stacks at harvest; but I think the high ° price is known by sensible thinking people to arise from other causes. I shall therefore proceed to observe, that farms of from 2001. to 800]. per annum, and upwards, are much more beneficial to the public, the landlord, and te- nant, than farms of from 501. to 1001. per annum. The public are benefited by fewer people and horses being kept upon bne farm of 3001. per annum, than upon six of 50l. each to do the same work, and therefore by a greater pro- duce being left, after the supply of the familtes, for the consumption of the kingdom at large. The 218 New Process for decomposing The landlord is benefited by having fewer buildings to erect and repair, and by having more opulent tenants. The benefit of a large farm to the occupier I need not enlarge upon. The misery of the small farmer, under 50]. per an- num, is extreme. He has not constant employment for himself and family (if at all large) upon his farm; he is in general aboye working day labour, 1s unable to exert him- self and improve his small tract of land, and sits by the fire-side with his family great part of the winter, lamenting that his farm and his capital are not larger, and brooding nothing but discontent and indolence. But while I am making these observations upon the ad- vantage of large over small farms, let me notice the great benefit and comfort that the common workman, in any line, derives from sufficient grass land being attached to his dwelling to keep a cow in summer and winter. The landlord will also receive benefit, as well as self-satisfaction, from being the cause of the plenty that the produce of a cow makes in.a large and poor family. I can from experience assert, that the cottager can afford to give his landlord one-third, if not one-half, more for that small quantity of land than a farmer. The value of the cow is generally more than one year’s rent, and the addition of a small cow-house is a trifling expense. : I cannot help recommending this the more strongly, be- cause I know well, from experience, the astonishing com- fort and advantage that a poor family receives from the pro- duce of its cow, and that it is also for the interest as well as inward satisfaction of the landlord. ) XXXII. New Process for decomposing Sulphate of Barytes in order to prepare the Muriate of that Earth; witha Method of preparing the Murtate, By M.GortTT.Linc*. Monrrare of barytes is now so generally used, that every improvement in the mode of preparing it must be fayoura- bly received. M. Goettling’s new method_is as follows : The decomposition of sulphate of barytes by means of charcoal requires a strong fire continued a long time, and never succeeds completely. This is owing, on the one hand, to the strongly oxygenated quality of the acidifying principle in the sulphuric acid, so that in its translation to the * From Taschen-luch fur Scheidkunstler. Sulphate of Barytes. 219 the charcoal it gives out but little caloric ; and on the other hand, to the ditliculty of imparting a certain degree of heat to a mixture into which a large quantity of a body that is so _ bad a conductor of heat as charcoal enters. To remedy the first of these defects, I had already proposed to increase the proportion of charcoal a little, and to incorporate with the mixture of charcoal and sulphate of barytes a twentieth of nitrate of potash. To remedy the second, Mr. Goettling advises to add muriate of soda to the mixture, which serves at the same time as a conductor of heat and a flux. The following is his method: Four parts of native sulphate of barytes in fine powder are to be mixed with one part of muriate of soda and half a part of charcoal powder. This mixture is to be pressed hard into a Hessian crucible, and exposed for an hour and half to a red heat in a good wind-furnace.. After it has grown cold, the mass is to be reduced to a coarse powder, and boiled for a moment with sixteen parts of water. The li- quor is then to be filtered, and kept in well stopped bottles. The time of exposure to heat may be shortened to one half, if the quantity of muriate of soda be doubled, and the matter occasionally stirred. ‘ In this case, too, double the quantity of water should be used to lixiviate the mass. To prepare muriate of barytes with this lixivium of sul- phuret of barytes, which at the same time holds in solution muriate of soda, muriatic acid is to be added in separate portions till sulphurated hydrogen gas is no longer extri- cated. The liquor is then to be filtered, a little hot water is to be poured on. the residuum, and the liquor is to be evaporated to a pellicle. The lixivium being then filtered afresh, is to be set to crystallize ; the muriate of soda, which is much more soluble in water than the muriate of barytes, and not more soluble with heat than without, is not depo- sited by cooling, and the muriate of barytes crystallizes alone. The remaining lixivium is to be evaporated and set to crystallize again, and this is to be repeated till no more crystals of muriate of barytes.are formed. The barytic salt thus obtained, if care be taken not to employ an excess of muriatic acid, is perfectly white, on account of the hydro-sulphuret, by which the iron and other metallic substances are precipitated. To be more certain that it contains no muriate of soda, the different products of the crystallization should be mixed together, dissolved, and re-crystallized. XXXIV. Re- ‘ [ 920 ] XXXIV, Report on the. Means of measuring the initial Velocity of Projectiles thrown from Cannon, both in an inclined and a horizontal Direction. . Read in the Phy- sical and Mathematical Class of the French National Institute in the Month of December 1804 *. se class charged Messrs. Bossut, Monge, and myself, to give in a report on the means for measuring the initial velocity of projectiles thrown from cannon, proposed by - colonel Grobert, who constructed an apparatus of such di- mensions that we could employ it for our preliminary ex- periments. This apparatus was as follows: A horizontal revolving axis, of about 34 decimetres in Jength, has at each of its extremities a disk or circle of pasteboard placed perpendicular to the axis, the centres of which are in the same axis, to which it is fastened in such a manner that the whole system can turn rapidly without the respective positions of 1 its different parts being deranged. The rotary motion is communicated to the axis and to the disks by means of a weight suspended at the extremity of a rope, which, after passing over a pulley raised ten or twelve yards above the ground, rolls itself round the arbor of a wheel and axle fixed at the same level as the disks. An endless chain, which passes round on the one side the wheel of the axle, and on the other a pulley fixed on the axis of the disks, transmit to that axis the motion which the weight cominunicates to the wheel and axle during its fall. This,apparatus, as is seen, has the merit “of being simples and without entering into further details it may be readily conceived how it can be employed for measuring hori- ental velocities. Let us suppose that the two aisks are. at rest, and that a ball traverses them in a direction pa- tal'el to the axis or the line passing through their centres ; it 's manifest that this axis wil] be in the same plane with the holes made in the disks; but if the disks turm around their axis while the ball passes from the one to the other, the plane containmg the axis of rotation and the first hole wil not coincide with the second hole; and if a second plane be made to pass through the second hole and the axis, the angle formed by these “two planes will be the measure of the are described by any point of the disks, while the ball or bullet. passes over the interval by which they are sepa- raved. * From the Journal des Mines, Floreal, an 12, no. 92, The Velocity of Projectiles thrown from Cannon. 271 * The question then is, to measure the velocity of the bullet. . : Ist, To impress an angular, uniform, and known velo- city to the system of the axis and the two disks. 2d, To measure the are comprehended between the two planes passing through the axis, and each of the holes or passages which the bullet has opened through the disks. In the experiments which were made, the motion became sensibly uniform when the weight had arrived nearly at the half of the vertical space which it traversed : this was ascer- tained by measuring at two pericds the time elapsed during the third and fourth quarters of the fall, and then comparing these times with the corresponding spaces passed over. For these measures we employed two excellent time-pieces that beat seconds; one by Louis Berthoud, and the other by Breguet. In almost the whole of the experiments we substituted for the measure of the vertical space passed over by the weight, that of the number of turns and fractions of turns made by the arbor of the wheel and: axle during a given number of seconds, which in every respect was much more precise and convenient. Then, to measure the arc passed over by the disks while the ball went from the one to the other, we placed before each of these disks a screen or fixed piece of pasteboard, which was at a very small distance from it; so that the balf during its passage first traversed the first screen, then the first disks then the second screen, and afterwards the se- cond disk. When the piece was discharged the hole ef the first disk was brought opposite to that of the first screen, and these two holes were in the same straight line with that made in the second screen; a wire, directed horizontally through the centre of the latter hole, pierced the second disk; and the arc, having its centre in the axis of rotation comprehended between the extremity of that wire and the centre of the hole made by the bal! in the second disk, gave the measure of the angle described by the system of the two disks, while the ball had passed over the length of the axis. : It may be readily seen that the fixed sereens, which give the absolute direction of the ball in space, furnish the means of making an allowance for the want of parallelism, if there be any between that direction and the axis of rotation of the disks. The cannon employed for throwing the projectile was placed horizontally and parallel to the arbor.of the disks, at a sufficient 299 Means of measuring the initial Velocity a sufficient distance from the first disk, that the motion given to the air by the explosion of the powder should not hurt the motion of that disk. An apparatus exactly similar to the above was established by colonel Grobert in a place belonging to the School of Bridges and Causeways, where, with the commissioners, he made, a few years ago, a great number of experiments, at which were present several officers of the engineers and artillery, among whom were general Marescot and the se- nator La Martilliere. This apparatus was far from having those dimensions and that perfection of which it was susceptible, and which the author proposes to give it. The object of the commis- sioners, therefore, was not so much to furnish results useful to the artillery, as to ascertain what advantage might be de- tived from it when constructed as it ought to be. It is proper, before we speak of our experiments, that we should resolve a difficulty which naturally occurs to all men who are in the least acquainted with this subject, and which arises from the enormous difference supposed to exist be- tween the velocity of a projectile thrown from a cannon and the angular velocity that may be given to the disks. It is concluded, indeed, from the experiments already known in regard to artillery, that the time employed by the ball or bullet in passing over the distance of three or four metres between the disks must be smaller than the hundredth part of a second, and it can hardiy be conceived that during so short a time the disks can describe a sensible are. The solution of this difficulty is as follows :—When the motion has become uniform, the wheel and axis make ge- nerally 0°833 turns per second, and the axis of the disks 7°875 turns, which thus made 6°56 turns per second, cor- respond to each turn of that wheel : therefore a point placed on one disk at the distance of a metre from the axis passed over about 41 metres per second, which gives for 1-100dth second 41 centimetres, a length more than sufficient to furnish very exact measures. The experiments were made with a common infantry musket and a horse musketoon, the barrels of which were resspectively 1°137 metre and 0°765 of interior length. They were charged with cartridges furnished from the arse- nal. The first series of experiments having been more re- gular than was presumed, they were encouraged to employ more precision in the charges and more care in the proofs. The balls were weighed exactly: their mean weight was 24°7 grammes, of Projectiles thrown from Cannon. 223 94*7 grammes, and each of them was projected with half its weight of powder. The following is the formula employed to calculate the velocity of the balls. The semi-circumference, which has unity for radius s - - - =r= 3141 The ratio between the respective numbers of the turns made at the same time by the wheel of the axle and the pulley of the axis of the disks - - - =f The time employed by the wheel of the axle to make z number of turns Sart The distance of the hole made by the ball in the second disk from the axis of the disks =r The arc passed over by that hole, while the disk goes from the one to the other - =@ The distance between the two disks - =b Velocity of the ball between the disks =V We have then the following equation : 241m =f Vis pet b. As it may be of some use to add to this formula a table of some experiments, we shall give the six following, made with the musketoon. i oo aaRTEEEn TEERERRGRTRTEEE Number of the n t a Vv Experiments Seconds. Metres. Metres. 1 8 10 0°3510 |) 402°3 2 8 10 0°3800 371°7 3 8 10 0°368 362°5 4 15 22 0°296 384°1 5 15 22 0° 264 430°7 6 10 18 0:268 345°7 ff 15 16 0°392 398°8 8 15 16 0°392 398.8 9 15 16 0°416 375°8 (0) 15 16 0:360 434°3 Teme Mean velocity = 390°45. Constant value of k = 7 a ; _ All the values of a are referred to that of ry = 1 metre. 5 The 224 Means-of measuring the initial Velocity _ The mean velocity deduced from the ten preceding expe- riments is 390°47 metres, nearly the same which results from the whole of the experiments. The mean value found for the velocity per second of balls thrown from the infantry musket was 428 metres, the ratio of which to the preceding is us 11to.l0. These experiments seem to indicate that the infantry musket might be shortened without much lessening its range ; but besides that the commissioners had no inten- tion of deducing from. these first trials any conclusions ap- plicable to artillery, it is proper to observe, that some mili- tary considerations, besides those of range; are in favour of Jeneth in an-infantry musket. If we wished to select from the accurate experiments hi- therto published in regard to the projectiles of artillery some proper for being nearly an object of comparison with those mentioned above, we might take from the work of doctor Hutton those which he made with a cannon of the smallest dimensions, and which he marks No. 1, the bore of it being 7 decimetres in length and about 51 millimetres in diameter. The general results consigned to a table formed from the whole of the experiments, give for the case, when the weight of the charge of powder is, as above, one-half that of the bullet, an initial velocity of 435 metres per se- cond, which differs very little from the velocity found with the infantry musket. Dr. Hutton’s pieces numbered 2, 3, and 4, and which were longer, gave mean velocities more considerable. The commissioners made some trials with half charges, that is to say, expelled the ball with the fourth part of its weight of powder: the mean value of the velocity of the ball thus projected was found for the infantry musket to be 254 metres, and)for the musketoon 252. These two velo- cities are sensibly equal, and exceed the halves 214 and 195 of those given by whole charges. There is reason to presume that these circumstances de- pend chiefly on the complete inflammation of the powder which takes place when there is only half a charge. In the last place, the commissioners, to multiply their trials on the application of colonel Grobert’s apparatus to horizontal firing, wished to obtain some data in regard to the resistance offered by the air to the motion of the ball, the diameter of which was 15 or 16 millimetres. The mouth of the barrel, which was first at the distance of 2°35 metres from the first fixed screen, was removed to that of 18°44 metres, by means of which its distance from the first fixed screen was 20°79 metres. In this position the velocity i ‘ ~ with of Projectiles thrown from Cannon. - 9285 With which the ball thrown from the infantry musket passed over the interval between the one disk and the other, was found at a mean value to be 345 metres per second instead of 428. The diminution is in the ratio of 42 to 34. The experiments of the last kind are few in number, and we shall deduce from them no conclusion: we shall not say any thing either of some trials which were made to deter- mine the loss of velocity which the ball experiences in - traversing the two first leaves of the pasteboard; as the principal object of our trials was not, a3 already said, to employ this first apparatus for the advancement of the science of artillery, but to acquire some idea of the advan- tage which this science might derive from it when con- structed with that pertection of which it is susceptible. One, of the most important changes which the author proposes is, to increase the diameter of the disks and the length of their axis in such a manner as to render them proper for determining the initial velocities of cannon balls of different calibres. It would be difficult to assign previ- ously, and without preliminary trials, the term of this aug- mentation compatible with the possibility and exactness of experiments ; but there is no doubt that the apparatus we used might be made of much greater dimensions, and such as might render it fit to be employed for trials with cannon. Colonei Grobert proposes another change, which derives its principal utility from that already mentioned. The ob- ject of it is to afford the means of traversing the disks by throwing balls in different directions, from the horizontal to that which forms half a right angle with the vertical line. To accomplish this end he has invented the follow- ing mechanism, which is simple and easily constructed :— He does not make the disks revolve around a common axis, but gives to each of them a particular horizontal axis, to which a pulley is affixed. The axis of the windlass has two equal wheels corresponding to two pulleys, and two endless chains, each of which passes round a wheel and a pulley. The rotary motion which the windlass receives from the descending weight is thus communicated to the disks, and the dimensions of the wheels and pulleys must be well re- gulated to make the disks turn together and to perform ex- actly the same number of revolutions in the same period. This condition being fulfilled, the supporter of one of the disks (that which is furthest from the cannon) is disposed in such a manner that it can rise vertically and fix itself at different heights, for each of which there are added some links to the chain corresponding to that disk, jn order to Vol. 22. No. 87. August 1805, P \ give ‘ 226 Means of measuring the initial Velocity give it sufficient length ; and by lowering the cannon it is thus possible to traverse the disks in different directions in- clined to the horizon. It may be remarked that the pro- jection of the surface of the disks on the plane perpendi- culat to the line of firing decreases more and more in pro- portion as that line inclines; but this is a very small in- convenience, as the greatest decrease which takes place in the ratio of about 7 to 5, leaves still a sufficient field for pointing with all the precision requisite. It will not, perhaps, be so easy as might at first be be- lieved to adjust the wheels, the pulleys, and the engage- ment, in such a manner as that the two disks may turn ex- actly together; we are, however, of opinion that there is nothing in this part of the apparatus which may not be made by any careful ingenious workman. Besides, if the machine be strong, and the parts well executed, there are means of avoiding the errors resulting from the want of co- ‘incidence which might exist in the motion of the disks. These means consist in counting the turns of ithe wheels made from the moment when the piece is fired till that when the machine stops, and causing these wheels to make the same number of turns in a contrary direction, and in such a manner that the wheels shall be brought to the . same respective positions in which they were when the piece was fired. We shall suppress several details relating both to the in- ‘clined range and to different pieccs of mechanism invented by colonel Grobert for supplying the attention and hand of man in the experiments. By means of these pieces of me- chanism the moving power, when it arrives at that point of its course where its motion becomes uniform, rests on two triggers, one of which causes a pendulum that swings se- conds to oscillate in order to count the time, while the other establishes a communication between the motion of the windlass and that of a system of toothed wheels and _pinions, furnished with an index to count the revolutions of the wheels. The weight, when it arrives at the lower extremity of its course, presses on other triggers which serve to set fire to the cannon, and to stop the counter of time and that of the number of turns. These different means may be useful, but it is sometimes attended’ with inconvenience to add too many parts to a piece of mecha- nism, and to make it so complex that it becomes liable to be deranged. Po8n As the above explanation will be sufficient to give an idea of the utility that may be derived from the apparatus of e ) Jone of Projectiles thrown from Cannon. 297 lone! Grobert, we shall now add a short account of the me- thods hitherto employed in researches of the same kind. It is only about sixty years ago that mathematicians be- gan to apply to the theory of projectiles. Benjamin Robins appears to us to have opened the way, or at least to have published the first experiments worthy the attention of phi- a ic and to have employed, for determining the iniual velocity of musket bullets, a pendulum, against which he threw his projectiles, and the sought-for velocity was de- duced from the amplitude of the oscillation: the same ma- thematician, when about to make particular experiments on gunpowder, deduced his results from the recoil of a small cannon attached to the lower part of the same pendulum *. The chevalier d’Arcy, of the Academy of Sciences, about eight or ten years after Robins’s work appeared, published, in the Memoirs of the Academy for 1751, a paper on the theory of artillery, containing a series of experiments made with great skill and care, and for which he employed, nearly in the same circumstances, two pendulums; against one of these he fired the ball, while the other, from which the small cannon was suspended, served to measure the recoil. In this manner he made those important experiments re- Jated in Exsais d’une Théorie de l Artillerie, published by the same author in 1760. Fifteen years after, Dr. Hutton, of the Royal Academy, Woolwich, made new experiments with the pendulum and projectiles, much heavier than those employed by Robins. An account of them may be seen in the Philosophical Transactions for 1778. About the same year count Rumford resumed and im- proved the method of making such experiments by means of a pendulum. He discovered a very simple way of sus- pending the cannon, in such a manner that the recoil took place without the axis ceasing to be horizontal. Dr. Hutton bestows great praise on these experiments, which are de- tailed in the Philosophical Transactions for 1781, and which have since been printed with considerable additions in a col- Jection entitled Philosophical Papers, &c. London 1802. In the last place, Dr. Huttan was employed during the years 1783, 1784, 1785, and 1786, on a numergus series of experiments, made with great care and expense, in regard to both kinds of pendulum. The collection of his memoirs, inserted in the Philosophical Transactions, and lately trans- ® Sce his Principles of Gunnery. ‘ Po lated \ 228 Means of measuring the initial Velocity tated mto French by colonel Villantroys, may be considered as the most complete and most instructive treatise on ba- listic experiments that ever appeared. The apparatus proposed by colonel Grobert, as may be seen, is very different from those employed by the authors above mentioned ; and whatever merit may be due to expe- timents made with pendulums, it must no doubt be allowed that it may be of some utility to make new ones by a very ingenious method, in which simplicity and ceconomy are united, and which leads to the propased end in the most direct manner, as the velocities sought for are deduced merely from the observation of the time employed by a moving body to make a certain number of revolutions around a fixed axis: an observation free from those dynamic calculations which are required by the method of Robins. We have said nothing of the labours of Antomi in regard to the object of this report, and yet we cannot omit men- tioning a machine which he speaks of in his Essai sur la Poudre, a French translation of which was published by M. de. Flavigni in 1773. This machine, which Antoni says was invented by a mechanician named Mathey, consists of a horizontal circle supported by its centre on the upper extremity of a vertical axis, and serving as a base to a hollow cylinder of paper. A rotary motion is given to this cy- linder by means of a weight affixed to a cord which passes over a pulley, and the projectile, thrown in a horizontal di- rection, when the angular velocity has become constant in the vertical plane of that axis, traverses the paper cylinder in two points. The distance of the second point from the diameter passing through the first, serves to measure the arc described by the system during the passage of the projectile in the interior of the hollow cylinder. It is incontestable, after this description, that the funda- mental idea of the process, by which a circular is compared with a rectilinear motion, belongs to Mathey ; but without entering into any detail on the inconveniences of this ma- chine, which no doubt have been the cause of its being little used, we shall content ourselves with observing that the apparatus of colonel Grobert differs from it ‘essentially. ist, By the horizontal position of its axis of rotation. The result of this difference is, that the axis can never be met by the projectile ; which makes it easy to ascertain the solidity and regularity of the position and motion: of the disks. | 2d, The projectile does not traverse a cylindric surface, but ‘ twa ef Projectiles thrown from Cannon. ' 229 two vertical planes, the extent and distance of which may be considerable, and which therefore may give very accu- rate measures. _ 3d, By the advantage it affords, not to be found in any other kind of apparatus yet known, of measuring the velu~ city of bullets of different sizes thrown in directions in- clined to the horizon. It remains fer us to give an account of some experiments made to ascertain that the ball underwent no sensible devia- tion in traversing the disks. It is manifest from the first principles of dynamics, that the moment when the ball is in the plane of one disk in motion, it receives perpendicu- Jarly to its direction an impulse which, according to certain mathematical hypotheses, would give it parallel to the plane of the disk a velocity almost equal to that of the point where it meets (the mass of the ball being very small in regard to those of the different moving. parts of the ma- chine) ; aud then the velocity of the ball, calculated accord- ing to the formula before given, would be infinite. The effective phenomena differ considerably from those deduced from similar hypotheses, considering the compressibility of the disks, their little hardness, and the prodigious rapidity with which they are penetrated* (the duration of the pas- sage of the semi-diameter through the disk not being the 40,000dth part of a second); but it is no less important to determine exactly the influence which they have on the re- sults. One of the commissioners is employed in analysing a dynamic problem, from which this determination may be concluded a priert; but as such a conclusion would not rest on physical data sufficiently certain, he preferred verifying by experiment whether the deviation was appreciable or not. For this purpose he placed three fixed screens at equal di- stances from each oiher ; the second and third being placed respectively betore the first and the second moveable disks. * It is here proper to give the reasoning on which these assertions are founded, Every body in nature being more or less compressible, the state of final motion, resulting from the action of two bodies on each other, is not acquired even at the moment of contact, but after a fixed term, which is very short; and bodies during their contact pass through all the interme- diate states ef motion between initial and final. From these incontestable facts, if one of the bodies escapes the action of the other before the moment when by the natural consequence of the shock they would have ceased to press each other mutually, the state of motion at which that body will really arrive in that case will differ so much less from its initial state, and so much more from that in which it would have been had the shock been consum- mated, as the contact has been of less duration, and this duration may be so short that the initial state is not sensibly modified. This is the case of the experiments mentioned in the text. P3 Tt 230 =—- Feilocity of Projectiles thrown from Cannon. It may be readily conceived that in the hypothesis of devia~ tion the hole made by the ball in the third fixed screen ought not to be in the same vertical plane with those made in the first and second screens; and thus this deviation be- comes easy to be ascertained and measured. Several balls were fired, the apparatus being arranged as here described. Each time a plumb-line was placed betore the centre of the hole made in the first sercen ; and taking in a line this thread and the centre of the hole made in the gecond screen, it was very easy to see whether the centre of the third hole was in the vertical plane containing the other two centres. These observations were made with care and precision, and yet it was not possible to perceive the devia- tion estimable in the direction of the line passing through the centres of the three holes: thus the motion of the bali through the moveable disks is sensibly the same as if these disks were at rest. We are of opinion, however, that it will be useful to employ always three screens, disposed as above, in the experiments made in future on this subject : by these means we may either ascertain whether there be any deviation, or discover whether it be sensible; and there can be no doubt that it will be so, either in the case when small velocities are communicated to the projectile, or, in general, in those where the ratio between that velocity and the resistance which the bullet experiences in traversing the disks shall exceed certain limits. It is proper to add, that the distance of the cannon from the furthest distant screen was about twelve metres, and that there was no reason to apprehend the inflections ob- served by Robins in distances of about a hundred metres, which according to him render rigorously the trajectory a curve of a double curvature. What we have said on the insensible effect which the action of the disk has upon the ball to make it deviate, proves that the re-action of the ball on the disk cannot di- minish its velocity by a sensible qnantity: this conclusion might be deduced, besides, from other facts, relative both to the mechanism of the apparatus and to the data furnished by the experiments, and particularly by the measure of time before and after the discharge of the piece :—but it 1s need- less to enter into further details. , To conclude: we are of opinion that the means to mea- sure the. jnitial velocity of projectiles thrown by fire-arms in directions both horizontal and inclined, proposed by co- lonel Grobert, and conformable to the summary description found in the above report, merit the approbation of the ; pit class. ] On the Buds and Ramifications of Plants. 23) class. We shall add, that a series of experiments made with an apparatus of Jarger dimensions, and executed with more care than that employed by the commissioners, might fur- nish results useful to artillery. XXXV. On the Buds and Ramifications of Plants; the Birth of these Organs, and the organic Relation between the Trunk and the Branches: in a Letter from G. L. Koeter, M.D. Professor of Botany and the Materia Medica in the Provisional School of Medicine at Mentz, to M. Ventenat, Memler of the French National In- stitute *, : MY DEAR FRIEND, ATURE seems to have thrown an impenetrable veil over the development of vegetable parts. In vain have botanists made efforts to surprise her; in vain'do they watch her ; she eludes their efforts, and laughs at their indefatigable patience. If it has been impossible, however, to accom- plish by observations this end, which was the object of so much care and labour, their researches have still conducted them to a multitude of other valuable discoveries, which have assisted us in the study of the structure and interior ceconomy of plants, and have shown to us the causes of several phenomena before considered as inexplicable. The opinions of those who have endeavoured to discover in what manner nature develops one vegetable organ from another may be ranged into two classes. Some have imagined that it is the pith, which makes its way through even the hardest wood to produce the ramifi- cations of plants, and that it lengthens itself still to form the most essential parts of the vegetable body, Others, and those the most recent, rejecting this opinion, have ascribed to the bark and cortical strata what their pre- decessors gave as the product of the pith. They ‘have thought also that the increase in length and thickness de- pends on the same organs. Placed between these two opinions, and though each of them was supported by great names, yet being unwilling jurare in verba magistri, 1 resolved to examine both with- out prejudice, and to give an opinion supported by my own observations. I did so; and discovered that Linnzeus and Hales, who had maintained the former opinion, were * From the Journal de Physique, Floreal, an 13. ; P4 ; not 232 On the Buds and Ramifications of Plants, not far from the truth ; that their error was very excusable, for they might easily take for pith the reproducing organ, which will be mentioned in the course of this letter, and the herbaceous substance of. which has a resemblance to that of this spongy organ. It may be said further in their favour, that they had not before them the experiments of Desfontaines, Coulomb, Hedwig, Mirbel, and Medicus, and so many other philosophers who have thrown light on a great number of points hitherto inexplicable in regard to the interior economy of vegetables. The observations which this study gave me an opportu- nity of making, have conducted me to results so unex~- pected, that [ did not think proper at first to trust to my own eyes. Convinced without being persuaded, and dis- trusting my own senses, especially in an experiment the results of which were in open contradiction to what we are taught by the greatest masters, I resolved to submit to you these observations, and to give them at the same time pub- licity, in order to call the attention of the most enlightened botanists to the new phznomenon which I think I have perceived, I must, however, say, that it is the force of con- viction, the desire of instruction, and not a vain spirit of controversy so unworthy of a real naturalist, which induce me to think differently from several celebrated men superior to envy, and to whom I readily pay the tribute of my gra- titude for the benefit I have received from their works, _ Before I give my observations on the origin of buds, I shall first rectify some ideas generally adopted in regard to these organs. ‘¢ The name of Jud is given in botany to small bodies more or less round or pe and covered with scales hol- Jowed out like a spoon, or with a down more or less thick. These organs are formed gradually in the spring season in the eyes of the leaves of most trees, shrubs, and plants of the dicotyledons, especially in climates where the winters are pretty severe. They contain and conceal the rudiments destined to be developed the following year into branches, leaves, and flowers. They have received trom nature the faculty of resisting cold and humidity: several of them may be preserved, hike a great many seeds, during one or more years, by remaining in a state of torpor until the develop- ment of their parts 1s excited by favourable circumstances.” These are the principles commonly received in regard to buds in genera}; but it appears to me that they are suited properly but to one species, that of most trees and shrubs in countries where the winter is pretty severe. 6 I shalt On the Buds and Ramifications of Plants. 233 I'shall now explain what, in my opinion, ought to be comprehended under the denomination of the luds of pha- negoram plants. 1 give this name to all the organs of these plants which contain the rudiments or germs of stems, branches, leaves, flowers, and even roots: each of these parts separately, or several of them united; or, im a word, the whole together. This name belongs to them whatever be their size; their number; that of the different parts of which they are composed ; the time of their appearance ; their property of being preserved ; the species which pro- duces them, and the place of their insertion: modifications and peculiarities which depend on the different structure of the plants as well as the circumstances under which they are placed. The definition I have given seems to me to unite several advantages: it embraces not only the whole of the organs together, even in regard to their origin; it dispenses also with the inconvenience of admitting a great number of ex- ceptions in the uniform progress of nature; exceptions which no doubt prove that they have not been sufficiently examined. It is pretended that shrubs are distinguished from bushes or trees by their ramifications not being the result of buds. This distinction is merely arbitrary, since these plants really produce them; but their buds are very small, exceedingly thin, destitute of dry scales, and some- times almost entirely concealed till the spring under the bark of the branches. Admitting the definition I have proposed, it will be ob- served that buds differ from each other by a great number of characters in the various species of plants. I shall here mention only those traits which are indispensably necessary to support my definition. In the igneous monocotyledon plants the whole course of life is confined to the development of the first bud, arising from the neck of the root or place where it is joined to the stem. This bud contains the germs of all the organs which appear above the earth, and the end of its development is the term also of the life of the same plant. These plants, however, generally live one, and even several, centuries. The propagation of plants by scions, by bulbs, and by other similar organs, which is very common to the herba- ceous monocotyledons, 1s not essentially different from that by buds, as has been completely proved by M. Mirbel and several other botanists. Scions and buibs are real buds; they are organs which contain the principles of new stems, branches, leaves, flowers, and roots. The part of the plant which 234 On the Buds and Ramifications of Plants. which produced them, and some modifications in/-tlicir structure, make them, however, be considered as species different from every other. Tt In the dicotyledon plants and the herlaceous monocot yle- dons the summit of the root bears during the carly age of the plant a single bud, named then plumula. This bud differs from that of the monocotyledon trees, as its deve- lopment is ended before the death of the individual, and ts ‘followed by other buds, in consequence of the development of which the plant raimifies. The monocotyledon trees produce also secondary buds, but with this difference, that these buds are pushed out by the primitive bud itself, and that they fade much sooner than that from which they pro- ceeded. In annual plants the development of all the buds of the individual is completed in the space of a year. In the i- ennial plants itis terminated at the end of two years.at most. Plants with a vivacious root but annual stem push.out every year another bud from the neck of the root: from the de- veloped parts of this principal bud other buds then issue, which make the ramifications of the vegetable appear. The buds of the three sorts of plants here mentioned are not all, or very rarely are, covered with other organs to pro+ tect the germs against the intemperance of the weather. Here nature, in general, may dispense with them, because these buds develop themselves in the course of a very short time, and almost always in the best seasons; and the plants, or at least the stems, to which they are indebted for their birth, perish im the winter, or even sooner. In most of these plants, as well as in bushes‘and some shrubs, the buds are-small, thin, and pointed, as in the vt- lurnum, the rhamnus (buckthorn), the heliotrupe, the cor- nel tree, the gramineous plants, the artemisia, &c. The ligneous dicotyledon plants ‘in general push forth their buds only in spring. Their buds im winter remain in- ' a state of inaction, and do not open till the return of spring. From this rule, however, are excluded all trees and bushes called evergreens, a great number of which perpe- tually send forth buds, so that the development of the leaves, branches, and even sometimes the flowers, never ceases during the life of these plants. Jn almost all the dicotyledon trecs and shrubs of the cold and temperate climates, the buds are formed in the eyes of the leaves, and always before the approach of winter. Bo- tanists consider the most exterior folioles of these buds as atorted folioles, because they are dry and even somctrmes : sonorous On the Buds and Ramifications of Plants. 235 sonorous under the fingers. They are called scales, on ac- count of their usual form. These organs are almost always covered with a resinous matter, which cements them very closely to each other, and which contributes not a little to «lefend the tender germs contained in the buds from the cold and moisture of the severe seasons. Ina great number of bushes and shrubs these scales are entirely wanting; but their, place is supplied in. several species by a down, which sometimes is pretty thick, and which affords sufficient protection to the buds against the rigour of the winter, as in the vidurnum and the pelea. In other buds of similar plants the parts still herbaceous and tender have neither down, nor scales, nor resinous matter, nor any other kind of covering, and they nevertheless with- stand the intemperance of the seasons, unless it be exces- sive. Among the latter there are some the folioles of which cover each otber firmly, as in the common lilac, the hazle, &c.; and there are some also in which the exterior folioles are neither so thick nor so firmly applied to each other as to be able to oppose the entrance of humidity, as 1s the case in the cornel tree. The luds of several ligneous dicotyledon plants remain, in regard to their base and a great. part of their body, con- cealed during winter under the bark, and their summit does not entirely open a passage for itsclf till the following spring. Here the bark serves as bandages to the tender elements of the new ramifications, as we see in a great tfumber of shrubs. ; Nature incloses the buds in several shrubs, as in the ler- Leris vulgaris, with petioles very close to each other ; it co- vers them also on one side by the branch from which they have proceeded, and on the other by the flat base of the prickles. In the last place, there are some ligneous dicotyledon ve- getables the buds of which are concealed and sheltered from the pernicious influence of the weather in a manner as sin- gular as wonderful. The buds, unprovided with scales, but covered with a fine and thick down, form themselves under. the concave base of the supporters of the leaves. During winter these supporters remain in their place in several plants; but when the sap ascends, the eye, becoming larger, rejects the tutor, of which it has no longer need. Some+ times shocks, and other accidents, make them fall earlier : in this case, the bud, being still secured by its natural pe- Jisse, escapes generally the severe cold of winter. ; I have observed that the supporter in question differs ac- cording 236 On the Buds and Ramifications of Plants. cording to its nature. In several plants it is a real petiole, as in the seringa, &c.; in others it is, as it were, an inter= mediate organ between the branches and the petioles, because it is not hollowed out in grooves at its upper surface, but entirely round ; because its substance is more ligneous than herbaceous, though it falls annually; and because it forms internally a canal containing real pith, and closed towards the base of the petiole, so that the pith does not commu- nicate with that of the part to which this supporter is at- tached. Similar supporters are found in the rhus coriaria, the acer negundo, the rebinta, &c. About three years ago I made this observation on the shumac ; and I have reason to believe that no one ever made it before.me, since [ in vain consulted on this subject all my books on botany. I proposed to make a series of researches on this subject ; and, indeed, they convinced me that nature covers in this manner the buds of several hig~ neous dicotyledons considered hitherto as not bearing any. It was my intention not to publish my observations until I had sufficiently repeated them, which could not be done till I had fk ee much greater number of vegetables. But a little while ago I found in the Mémoires pour servir & ? Anatomie et a la Physiologie Végéiales, par M. Medicus*, that this celebrated botanist had made the same observation on plane-trees. {immediately had recourse to other works, such as your excellent Tableax du Regne Végétal; and, though I found nothing in the first volume under the arti- cles relating to that subject, I found in the third ¢ that this peculiarity of the plane-tree had not escaped you. I then consulted the Traité des Arbres et Arbustes, by Duhamel, where, under the article Platanus, this great observer makes mention of the same phenomenon, without pointing out, however, whether it was known before; but as it has been known since that trme, how comes it that no botanist, in treating specially of buds, has rectified his definition ac- cording to this observation ? Shumac furnished me also with an opportunity of ob- serving several. phenomena in regard to the dirth and deve- lopment of buds. 1 shall give you an account of them as briefly as possible. Almost all botanists have adopted the opinion, that the leaves in-the eyes of which the buds shoot forth approach, towards the end of their life, to the ligneous state by the * Beytrage zur Pflanzen anatomie und Pfanxen physiologie, haft i. p. 24, + Page 572. influence On the Buds and Ramifications of Plants. 937 influence of the rays of the sun and of the air, and that they then no longer afford a free passage to the ascending sap. It is supposed that the fluids stop, and are accumulated at the base of these leaves, and that they thereby give birth to cambium, which occasions the ring or swelling there ob- served. It is pretended also that this camliwm produces new vessels, which, obeying the impulse they daily receive from the ascending sap, become lengthened towards the surface of the bark, and force themselves to pierce it; after which they give birth to the bud. This explanation, though ingenious, appears to me to be only a bold hypothesis, supported by facts which have not been examined with sufficient care. Instead of begin- ning by an explanation, it would have been better to discover first all the facts and all the circumstances by which this phenomenon is accompanied. And still we shall succeed ‘as little in penetrating into this operation as we have done in regard to all the rest, the secret of which nature seems ‘to have reserved to herself: the formation of the individuals and of their organs will be always inexplicable to us. Na- ture; however, far from precluding us from researches, ex- cites us rather to watch her; and it is then that, by attend- ing with assiduity and without prejudice, we often discover facts which form one step towards the truth. It may be objected to this explanation, that there are, indeed, buds which do not pierce the bark in the eyes of the leaves, and that the eye shows itself already at the time when the leaves ‘have Jost none of their vigour. to. ‘J shall now return to my own observations. In exa- mining with attention the ligneous dicotyledon plants at ‘the different seasons, it will be observed that a body almost always soft, kerbaceous, and green, when it issues from the wood, enters into the bud destined to develop flowers or a branch, and that this body forms in reality the centre or axis of the bud. The same observation will be made when the wood of the branch which throws out the bud is already formed of several annual zones. [twill be perccived also that this herbaceous body is rarely alone ; that it has, for the most part, on each side, and at.a very small distance from it, another ledy, and sometimes two, but of the same sub- Stance as itself: these lateral herbaceous lodies are smaller than it, and never penetrate into the substance of a bud which produces branches or flowers: they enter into those only of the leaves; that is to say, into those a petiole or jeaf of which is destined to develop itself, which we observe at the base of a twig in several shrubs and bushes. There is 238 On the Buds and Ramifications of Plants. is sometimes also at the base, and very near the largest herbaceous body, a similar body, which penetrates on it into the same bud. All these herbaceous bodies are produced each separately in a medullary sheath, and never in the bark, the liber, or the alburnum, nor in the annual zones of the wood, They are indeed the prolongations of the bundles of tubes of the medullary sheath*. The herbaceous bodies of which I here speak, in passing into the wood are not always in a horizontal direction: f mean, that they do not form in all the plants which I have examined a right angle with the medullary sheath: in se- veral trees and shrubs they Jeave it much lower than the place where the bud issues from the bark, as is the case m the shumac, plane-tree, willows, &c. When the bark, with the bud, has been removed, these herbaceous prolongations present themselves under different forms, according to the species to which they belong, the age of the branch, the place even where they are, and the angle at which they have traversed the wood. This is the reason why the figure of their section in the exterior zone of the wood varies from the form of a line or stroke to that of a point entirely round; sometimes there are several of them united, so that altogether they form scarcely a single line or oblong point. At the place where these herbaceous - bodies traverse the wood, the ligneous fibres are separated from each other; and though they press them more or less, they still leave them a sufficient passage. This separation . of the tubes and fibres of the wood is more apparent in the zones near to the medullary case, than in those which are more distant, and consequently nearer to the bark. The thickness of these bodies differs also in the different species of plants. In those the wood of which is hard and compact they are smaller, and at the same time less cylin- dric than in those the wood of which is light. Those de- stined to push forth buds for twigs and flowers haye more volume than those which produce leat-buds. They do not always remain green: they lose that colour as they change into wood. But they are found herbaceous, and filled with green substance, at least, until the bud has expanded into a flower-bud; and I have observed that they are still green and-herbaceous, even in the twigs and young branches, if the wood of the species from which they have proceeded be white and light. * These vessels are porous tubes, large simple tubes, trachex, and false trachex. See Tirairé d’ Anatomie et de Physioiogie végétules, par Brisseau Mirlel, vol. i- p, 186, et seq.; and the same in Dict. des Sciences Naturelles, vol. ii. P- 369. ~ 5 | SBhe On the Buds and Ramifications of Plants. 939° *'The same prolongations are found in herbaceous plants with a ramified stem: for example, in the adult stems of the common cabbage, &c., where one may be convinced that the branches have no other origin there than that of the medullary sheath, and that they issue from real buds. It seems to result, from what I have here said, that the reproducing, organ of buds in the dicotyledon plants, is effectively and exclusively the case or sheath which contains the pith: it is even in the herbaceous monocotyledon plants, the spaces between the knots of which form empty tubes: nature, to produce branches, has formed m these plants solid knots or articulations, the structure of which is almost the same as that of the stems of plants the canal of which contains pith. The opinion that the medullary case is the only organ which gives rise to buds, and consequently to branches, is confirmed by the observations which J made on the inser- tion of old branches even in trunks entirely dry. For this purpose I carefully examined the branches of the pine fiz and prunus~ spinosa (sloe-tree), shumac, oak, apple-tree, &e., and every where I observed the same result. It is true, that in the old branches the prolongations are more herbaceous, and on that account are difficult to be distin- guished, because the one which has penctrated into the. principal substance of the bud, from which the branch has proceeded, has become ligneous : the small lateral ones are not even dried, and are still entirely covered and concealed both by the base of the branch, and by the annual strata of the wood, which had been formed after these prolongations had thrown out petioles or leaves. The perpendicular sec- tion of a branched trunk always shows, whatever be the number of the concentric strata of the ligneous body, that the medullary sheath of the branch proceeds from the medullary sheath of the trunk ; that the branch never forms in the trunk an inverted cone, the summit of which is con- cealed by the strata of that part; and that the branch of a tree can never be compared, as has been done, to @ plant the roots of which are ina ligneous soil. The different an- ual strata of a branch never cover each other, in any case, at their respective bases ; and they are never separated from those of the trunk. These strata are in immediate com- munication with those of the trunk, in such a manner that the strata of the branch seem to have arisen from a pro- Jongation of those of the trunk. © Itis very difficult to di- stinguish whether the medullary sheath takes its tt TOU, 240 On the Buds and Ramifications of Plants. from that of the trunk, when the medullary canal of that part is filled with ligneous strata, which is the case in se- veral bushes and shrubs where an interior liber is formed annually of the pith, until the canal which contains it has altogether disappeared, as in the ash, the oak, shumac, &c. ; but it is principally in the latter that we may be con- vinced that it is never by the medullary sheath, nor by the interior cambium, that these internal zones are produced. The increase in length of buds and twigs is ascribed to an erection of the yo of the liber, If the bark of a "young branch be separated as far as the terminal bud in a young poplar, for example, and particularly before winter, — or in the following spring, it will be found that the inner. bark has never become lengthened. The upper part of a branch and a flower-bnd is formed only by the pith, the medullary sheath, and the bark. I think I may conclude from this observation, that the increase of the stems or trunks, and the ramifications, depends merely on the elongation of the vessels of the medullary sheath. The allurnum, the tubes of which have a direction perfectly straight, presents itself at the upper part of a branch under the form of separate fibres, which Jose themselves at the surface of the medullary sheath. his observation explains to us also why the zones of the upper part of a branch are in number inferior to those of the base. It confirms also what I have said in regard to the birth of buds ; for, if we examine the bud of a small branch in any tree whatever, we shall be convinced that it is the medullary sheath with- — out exception that composes alone the interior of that organ. Explanation of the figures belonging to the above article. See Plate III. Fig. 1, A vertical section of a piece of a branch of shumac. A, The bark. B, Ligneous zone of one year. C, The medullary sheath. D, A bud. . E, The swelled-up part of the bark at the base of the ud. F, Herbaceous prolongation of the medullary sheath, «which has traversed the wood and given birth to the bud. G, The pith. Fig..2, On the Buds and Ramifications of Plants. 241 Fig. 2, A siinilar, cut obliquely at the place where the prolongation passes through the wood, A; Abud. . B, The bark. C, Ligneous zone of the year. D, Herbaceous prolongation of the medullary sheath passing through the wood and entering the bud. E, The swelled part of the bark at the sides of the bud. F, The pith. G, The medullary sheath. Fig. 3, The same piece seen in profile, to show, the angle of the section. Fig. 4, Vertical section of a piece of shumac of two years old, bearing a bud. . A, The bud produced from an herbaceous prolongation of the medullary sheath, which prolongation has passed through the two ligneous strata. Fig. 5, Vertical section of a branched piece of shumac. A, The bark. B, Ligneous stratum of the second year. C, Ligneous stratum of the first year. } D, Stratum arising from the lignification of the exterior part of the pith. E, Medullary sheath of a branch. F, Medullary sheath of a twig. G, Pith, H, Prolongation of the medullary sheath, become lig- neous, and confounded with the wood produced by the pith. Fig. 6, Vertical section of a branched piece of the pla- tanus occidentalis. A, Pith. B, Medullary sheaths. C, Ligneous stratum of the first year. _ D, Ligneous stratum of the second year. -E, Lignified prolongations of the medullary sheath. Fig. 7, Vertical section of a piece of hazle, bearing a twig with false wood, which has only_one lyneous zone, and which has arisen from a prolongation of the medullary sheath, which prolongation, in order to produce the bud from which the twig resulted, has passed through seven zones of wood, and at length become ligneous. (To be concluded in our next.) Vol. 22. No. 87. August 1805. @Q XXXVI. Method { 242 Jo KXXVI. Method of obviating the Necessity of lifting Ships. By Mr. Rovert Sepeines, of Chatham Yard*. Tus following is 2 description of an invention by Mr. Robert Seppings, late master shipwright assistant in his majesty’s yard at Plymouth (now master shipwright at his majesty’s yard, Chatham), for suspending, instead of lifting, ships, for the purpose of clearing them from their blocks, by which a very great saying wil! accrue to the pub- lic, and also two-thirds of the time formerly used in this operation. From the saving of time another very important advan- tage is derived, namely, that of enabling large ships to be docked, suspended, and undocked, the same spring tides. Without enumerating the inconveniencies arising, and, perhaps, injuries, which ships are liable to sustain, from the former practice of lifting them, and which are removed by the present plan ;. that which relates to manual labour de- serves particular attention ; twenty men being sufficient to suspend a first-rate, whereas it would require upwards of 500 to lift her. The situation which Mr. Seppings held in Plymouth-yard, attached to him, in a great degree, the ‘shoring and lifting of ships, as well asthe other practical part of the profession of a shipwright. Here he bad an opportunity Of observing, and indeed it was a subject of general regret, how much time, expense, and labour, were required in lifting a ship, particularly ships of the line. This induced him to consider whether some contrivance could not be adopted to obviate these evils. And it occurred to’ him, that if he could so construct the blocks on which the ship rests, that the weight of the ship might be applied to assist in the operation, he should accomplish this very de- sirable end. In September 1800, the shoring and lifting the San Josef, a large Spanish first-rate, then in dock at Plymouth, was committed to his directions ; to perform which, the assistance of the principal part of the artificers of the yard was requisite. In conducting this business, the plan, which will be hereafter described, oceurred to his mind; and from that time, he, by various experiments, proved his theory to be correct: the blocks, constructed by him, upon which the ship rests, being so contrived, that the facility in removing them, is proportionate to the quan- tity of pressure; and this circumstance is always absolutely * From thé Transactions of the Socicty of Ants, who voted him the gold medal, 1804. 8 - under On obviating the Necessity of lifting Ships. 243 tinder command, by increasing or diminishing the angle of three wedges, which constitute one of the blocks; two of which are horizontal, and one vertical. By enlarging the angle of the horizontal wedges, the vertical wedge becomes of consequence more acute} and its power may be so in- creased, that it shall have a great tendency to displace the horizontal wedges, as was proved by a model, which ac- companied the statement to the society ; where the power of the screw is used as a substitute for the pressure of the ship. Mr. Seppings caused three blocks to be made of hard wood agreeable to his invention, and the wedges of various angles. The horizontal wedges of the first block were nine decrees ; of the second, seven; and of the third, five ; of course, the angle of the vertical wedge of the first block was 162 degrees; of the second, 166; and of the third, 170. These blocks, or wedges, were well executed, and rubbed over with soft soap for the purpose of experiment. They were then placed in a dock, in his majesty’s yard, at Ply- mouth, in which a sloop of war was to be docked: on exa- mining them after the vessel was in, and the water gone, they were all found to have kept their situations, as placed before the ship rested upon them. | Shores in their wake were then erected to sustain the ship, prior to the said blocks being*taken from under the keel. The process of clearing them was, by applying the power of battering- rams to the sides of the outer ends of the horizontal wedges} alternate blows being given fore and aft; by which means they immediately receded, and the vertical wedges were disengaged. It was observed, even in this small ship, that the block which was formed of horizontal wedges of nine degrees, came away much easier than those of seven, and the one of seven than that of five. In removing the afore- said biocks by the power of the battering-rams, which were suspended in the hands of the men employed, by. their holding ropes passed through holes for that purpose, it was remarked by Mr. Seppings, that the operation was very la- borious to the people; they having to support the weight of the battering-rams, as well as to set. them in motion. He then conceived an idea of afixing wheels near the ex- tremity of that part of the rams which strikes the wedges. This was done before the blocks were again placed ; and it has since béen found fully to answer the purpose intended, particularly in returning, the horizontal wedges to. their original situations, when the work is performed for which they were displaced ; the wheelsalso giving a great increase of O2 power 244 ; Method of obviating power to the rams, and decrease of labour to the artificers ; besides which, the blows are given with much more exact- ness. The same blocks were again Jaid in another dock, in which a two-decked ship of the line was docked. On exa- mination they were found to be very severely pressed, but were removed with great ease. They were again placed in another dock in which a three-decked ship of the line was docked. This ship having in her foremast and bowsprit, the blocks were put quite forward, that being the part which . presses them with the greatest force. As.soon as the water was out of the dock, it was observed that the horizontal wedges of nine and seven degrees had receded some feet from their original situations. This afforded Mr. Seppings a satisfactory proof, which experience has since demon- strated (though many persons before would not admit of, and others could not understand, the principle), that the facility of removing the blocks or wedges, was proportionate ,to the quantity of pressure upon them. The block of five degrees kept its place, but was immediately cleared, by ap- plying the power of the battering-rams to the sides of the outer ends of the horizontal wedges. The above experi- ménts being communicated to the Navy Board, Mr. Sep- pings was directed to attend them, and explain the prin- ciple of his invention; which explanation, further corro-. borated by the testimonials of his then superior officers, was so satisfactory, that a dock was ordered to be fitted at Plymouth under bis immediate directions. The horizontal wedges in this, and in the other docks, that were afterwards fitted by him, are of cast iron, with an angle of about five degrees and a half, which, from repeated trials, are found equal to any pressure, having in no instance receded, and, when required, were easily removed. The vertical wedee is of wood, lined with a plate of wrought iron, half an inch thick. On the bottom of the dock, in the wake of each block, is a plate of iron of three quarters of an inch thick, sO that i iron at all times acts in contact with iron. The placing the sustaining shores, the form and sizes of the wedges, and battering-rams, &c. ; also the process of taking away, and again replacing, the wedges of which the block is composed, “are also exemplified by a model. The dock being prepared at Plymouth, in August 1801 the Canopus, a large French 80-gun ship, was “taken in, and rested upon the blocks; and the complete succeds of the experiment was such, that other docks were ordered to be fitted at Sheerness and Portsmouth dock-yards, under Mr. Seppings’s divections. At the former place a Sig see an the Necessity of lifting Ships. 245 and at the latter a three-decked ship, were suspended in like manner. This happened. in December 1802, and - January 1803; and the reports were so favourable, as to cause directions to be given for the general adoption of these blocks in his majesty’s yards. This invention being thought of national consequence, with respect to ships, but particularly those of the navy, government has been pleased to notice and reward Mr. Seppings for it. The time required to disengage each block is from one to three minutes after the shores are placed: and a first-rate sits on about fifty blocks. Various are the causes for which a ship may be required to be cleared from her blocks, viz. to shift the main keel; to add additional fasle keel; to repair defects; to caulk the garboard seams, scarples of the keel, &c. Imperfections in the false keel, which are so very injurious to the cables, can, in the largest ship, be remedied in a few hours by this invention, without adding an additional shore, by taking away blocks forward, amid- ships, and abaft, at the same time; and, when the keel is repaired in the wake of those blocks, by returning them into their places, and then by taking out the next, and so on in succession. The blocks can be replaced in their ori- ginal situations, by the application of the wheel battering- rams to the wedges, the power of which is so very great, that the weight of the ship can be taken from the shores that were placed to sustain her. There were one hundred and six ships of different classes, lifted at Plymouth dock- yard, from the 1st of Jannary 1798 to the 31st of Decem- ber 1800; and, had the operation of lifting taken less time, the number would have been very considerably increased ; for the saving of a day is very frequently the cause of saving . a spring tide, which makes the difference of a fortnight. The importance of this expedition, in time of war, cannot be sufficiently estimated. This invention may be applied with great advaniage, whenever it is necessary to erect shores, to support any great weights, as, for instance, to prop up a building during the repair of its foundation, &c. © Captain Wells, of his majesty’s ship Glory, of 98 guns, used wedges of Mr. Sep- pings’s invention for a fid of a top-gallant mast of that ship. In 1803, the top-gallant masts of the Defence, of 74 guns, were fitted on this principle by Mr. Seppings : ‘and, from repeated trials, since she has been cruiziug in the North Sea, the wedge fids have been found in every respect to answer. But itis Mr, Seppings’s wish that it should be under~ 3 stood, 246 Method of obviating stood, that the idea of applying this invention to the fid of a top-gallant mast origmated with captain Wells, who well understood the principle, and had received from him a model of the invention. When it is required to strike a top-gallant mast, the top ropes are hove tight, and the pin which keeps the horizontal wedges in their place i is taken out, by one man going aloft for that purpose; the other horizontal wedge is worked in the fid, as shown in the drawing and model that accompany this statement. The upper part of the fid hole is cut to form the vertical wedge. The advantage derived from fid- ding top-gallant masts in this way is, that they can be struck at the shortest notice, and without slacking the rig- | ging, which is frequently the cause of springing and carry= ing them aw ay, particularly those with long pole heads. The angle of the horizontal wedges for the fids of masts should be about tw enty degrees. The above account was accompanied with certificates from sir John Henslow, surveyor of the navy; Mr. M, Didram, master-shipwright of Portsmouth- yard; and Mr. Jobn Carpenter, foreman of Sheerness dock-yard, con-_ firming Mr. Seppings’s statement. Reference to the Engraving of Mr. Seppings’s method of obviating the necessity of lifting ships. Plate IV. This plan and section of a seventy-four gun ship de~ scribes the method of obviating the necessity of lifting ships, when there may be occasion to put ‘additional false keels to them, or to make good the imperfections of those already on; also, when it may be necessary, to caulk the garboard seams, scarples, the keel, &c.; by which means a very con- siderable part of the expense will be saved, and much time gained. The blocks are cleared, and again returned by the following process. A sufficient number of shores are placed under the ship to sustain her weight, and set taught, sta- tioned as near the keel as the working of the battering- rams fore and aft will admit. Avoid placing any opposite the blocks, as they would in that case hinder the return of the wede'es with the battering-rams. A blow must then be given “forward on the outer end of the iron wedges with the bat tering-rams in a fore and aft direction, which will cause them to slide aft, as shown in the plan. The batter~ ing rams abaft then return the blow, and the wedges again come forward; ‘by the repetition of this operation, “the wedges will be with great ease cleared, and the angular block the Necessity of lifting Ships. 247 , block on the top will drop down. When the work is per- formed, the block must be replaced under the keel, and the wedges driven back bw working the rams athwart-ships, as described in the section. N.B. In returning.the iron wedges, to avoid straining the angular blocks, it is proposed to leave a few of them out forward and aft, and stop the ship up, by laying one iron wedge on the other, as shown at Fig. 1, Plate IV. To facilitate the business, blocks may be cleared forward and aft at the same time, sufficient to get in place one length of false keel. If the false keel should want repairing, it may bedone without any additional shores, by clearing one block at a time; and when the keel is repaired in the wake of that block, return the wedges, as above directed, and clear the next, &c, ' Section and Plan, Plate IV. Fic. 2, A, Keelson. B, Ceiling. C, Floor timber. D, Dead or rising wood. E, Plank of the bottom. F, Keel ard false keel. G, Angular blocks with a half-inch iron-plate bolted to them. H, Cast-iron wedges. I, Irén-plate of three-fourths of an inch thick on the bottom of the dock. die) : K, Batteting-rams, with wheels, and ropes for the hands. L, Cast-iron wedges, having received a blow from for- Ward. . M, Shores under the ship to sustain her weight. Fig. 3. represents part of a top-gallant mast fitted with a wedge fid. a, Top-gallant mast. , Fid, with one horizontal wedge worked on it. ¢, Moveable wedge, with the iron strap and pin over it, to keep it in its situation, d, Trussel trees, 04 XXXVII. On [248 «J XXXAVIT. On the Variations ie Terrestrial Magnetism in different Latitudes. By Messteurs HumBoupr and Biot. Read ly M. Bior, jn the Mathematical and Physical Class of the French National Institute agi Frimaire, An 13*. (17th December 1804.) As i inquiry into the laws of terrestrial magnetism is no doubt_one of the most important questions that philoso- phers can propose. The observations already made on this subject have discovered phenomena so curious, that one cannot help endeavouring to solve the difficulties they pre- sent; but notwithstanding the efforts hitherto employ ed, it must be confessed that we are absolutely unacquainted with the causes of them. It was difficult to obtain on this point any precise know- ledge at a time when the construction of - the compass was still imperfect; and so little time has elapsed since the discoveries of M. Coulomb have taught us to render them completely exact, it needs excite no astonishment that so few facts in the HG | ee of traveliers haye been found worthy of confidence The expedition which M. Humboldt has terminated has procured for this part of philosophy a collection no less valuable than those, with which he has enriched the other branches of human knowledge. Furnished with an excel = lent dipping-needle, constructed by Le Noir on the princi- ples of Berda, M. Humboldt has made more than three hundred observations on the inclination of the m agnet, and on the intensity of the magnetie force in that part of Ame- rica which he traversed. By adding to these results those which he had already obtained in “Europe before his de-» parture, we shall have for the first time a sertes of correct facts on the variation of the magnetic forces in the northern part of the globe, and. in some points of its, southern part. . The friendship which M. Humboldt has. testified for me since his return having given me an opportunity of commu- nicating to him some experiments on this subject, which I made this year in the Alps, he immediately offered to unite his to mine ina memoir. But if friendship and a desire of making known new facts induced me to accept this offer of M. tlumboldt, justice forbids me to take ad- vantage of it to his prejudice ; and J must here declare, that a very smal] part of it elongs to me. * From the Journal de Physique, Frimaire, An 13. | To On the Variations of the Terrestrial Magnétism. 249 To place in order the facts and consequences which may be deduced from them, it is necessary to consider the ac- tion of terrestrial magnetism under different points of view, corresponding to the different classes of the phenomena which it produces. If we consider it first.in general, we find that it acts on the whole surface of the globe, and that it extends beyond it. This last fact, which was doubted, has been lately proved by one of us, and particularly by our friend M. Gay- Lussac, during his two aérostatic voyages. And if these observations, made with all the care possible, have not shown the least sensible diminution in the intensity of the magnetic force, at the greatest height to which man can attain, we have a right to conclude that this force extends to an irae 6 distance from the earth, where it decreases, perhaps, in a very rapid manner, but which at present is_ unknown to us. If we now consider magnetism at the surface even of the earth, we shall find three grand classes of phznomena, which it is necessary to study separately, in order to have a complete knowledge of its mode of action. "These pheno- mena are; the declination of the magnetic needle, its incli- nation, and the intensity of the m aunetic force, considered either comparatively in different places or in ‘themselves, paying attention to the variations which they experiences {tis thus that, after having discovered the action of gravity as a central force, its variation, resulting from the figure of the earth, was afterwards astemtaindd in. different lati- tudes. The declination of the magnetic needle appears to be that phenomenon which hitherto has, more _ particularly fixed the attention of philosophers, on account, no doubt, of the assistance which they hoped to derive from it in de- termining the longitude ; but when it was known that the declination changes i in os same place, in the course of time, when its “diurnal variations were remark ed, and its irregular traversing, occasioned by different meteors ; in a word, the difficulty y of observing it at sea, within one de- gree nearly, it was necessary to ~abandon that hope, and to consider the cause of these: phenomena as much more com- plex and abstruse than had been at first imagined, In regard tothe intensity of the magnetic force in diffe- rent parts of the earth, it has never yet been measured in a comparative manner. ‘The observations of M. Humboldt on this subject have discovered a very remarkable pheno- menon ; it is the variation of the intensity in different lati 1 tudes, 250 Variations of the Terrestrial Magnetism tudes, and its increase proceeding from the equator to the oles. The compass, indeed, which at the departure of M. Humboldt gave at Paris 245 oscillations in 10 minutes, gave no more in Peru than 211, and it constantly varied in the same direction ; that is to say, the number of the oscil- Jations always decreased. in approaching the equator, and always increased in advancing towards the north. These differences cannot be ascribed to a diminution of force in the magnetism of the compass, nor can we sup- pose that it is weakened by the effect of time and of heat; for, after three years” residence in the warmest countries of the earth, the same compass gave again in Mexico oscilla- tions as rapid as at Paris. - There is no reason, either, to doubt the justness of M. Humboldt’s observations, for he often observed the oscilla- tions in the vertical plane perpendicular to that meridian ; but by decomposing the magnetic force in the latter plane, and comparing it with its total action, which is exercised in the former, we may from these data calculate its direction, and consequently the direction of the needle*. This in- clination, thus calculated, is found always conformable to that which M. Humboldt observed directly. When he made his experiments, however, he could not foresee that they would be subjected to this proof by which M. La Place verified them. As the justness of these observations cannot be contested, we must allow also the truth of the result which they indi- * Let HOC (plate V. fig. 1.) be the plane of the magnetic meridian pass- ing through the vertical O C;let OL be the direction of the needle situated in that plane, and OH ahorizontal. The angle LOH willbe the inclination of the needle, which we shall denote by I. If F represent the total mag- netic force which acts in the direction OL, the part of this force, which acts according to OC, will be F sine of I: but the magnetic forces which deter- mine the oscillations of the néedle in any plane, are to each other as the squares of the oscillations madé in the same time. If we denotethen by M, the number of the oscillations made in 10’ of time in the magnetic meridian, and by P, the number of oscillations made also in 10’,in the perpendicular plane, we shall have the following proportion. F sin. I omy Pp sh hae Taga from which we deduce PF sin. I = — in Me The inclination then may be calculated by this formula, when we have oscillations made in the two planes. : In like manner, by making a needle oscillate successively in several vertical planes,,we might determine the direction of the magnetic meridian. _ cates in different Latitudes. 25) cate, and which is the increase of the magnetic force pro- ceeding from the equator to the poles. ‘ To tollow these results with more facility it will be proper to set out from a fixed term, and it appears natural to make choice for that purpose of the points where the inclination of the magnetic needle is null, becatise they scem to indi- cate the places where the opposite action of the two terres+ trial hemispheres is equal. The series of these points forms on the surface of the earth a curved line which differs very sensibly from the terrestrial equator, from which it deviates to the south in the Atlantic : a and to the north in the South Sea. This curve has been called the magnetic equa- ior, from its analogy to the terrestrial equator, though it 1s not yet known whether it forms exactly a great circle of the earth. We shall examine this question hereafter; at pre- sent it will be sufficient to say, that M. Humboldt found this equator in Peru about 7°7963° (7° 1’) of south latitude, which places it, for that part of the earth, nearly in the spot where Wilke and Lemonnier had fixed it. Fhe places situated to the north of that point may be di- vided into four zones; the three first of which, being nearer the equator, are about 4°5° (4°) of breadth in latitude; while the latter, more extensive and more variable, is 16° (14°). So that the system of these zones extends in Ame- rica from the magnetic equator to 25°5556° (23°) of north latitude, and comprehends in Jongitude an interval of about 56° (50°). The first zone extends from 7°7963° (7° 1”) of south latitude to 3°22° (2° 54’). The mean number of the oscillations of the needle in the magnetic meridian in 10’ of time is there, 211°9: no observation gives less than 211, or more than 214. From M. Humboldt’s observations one might form a similar zone on the south side of the magnetic equator, which would give the same results. The second zone extends from 2°4630° (2° 13’) of south Jatitude to 3°61° (3° 15’) of north latitude. The mean term of the oscillations is there, 217°9: they are never below 220, or above 226. , The fourth zone, broader than the other two, extends from 10°2778° (9° 15’) to 25*7037° (23° 8’) of north lati- tude. Its mean term is 237: it never’ presents any ob- servation below 229, or above 240. We are unacquainted, in reyard to this part of the earth, with the intensity of the magnetic force beyond the latitude of 26° (23°) north; and on the other hand, in Europe, where we have observations made in high viuaceeiar: we avi 252 Variations of the Terrestrial Magnetism have none in the neighbourhood of the equator: but we will not venture to compare these two classes of observa- tions, which may belong to different systems of forces, as will hé- ‘mentioned hereafter. However, the only comparison of seanlisk collected in America by M. Humboldt, appears to us to establish with -ceriainty the increase of the magnetic force from the equa- tor to the poles; and, without wishing to connect them too closely with the experiments made in Europe, we must romark, that the latter accord so far also with the preceding as to indicaie the phenomenon. If we have thus divided the observations into zones pa- ralle! to the equator, it is in order that we may more easily siiow the truth of the fact which results from them, and in. pariicular to render the demonstration independent of: those small anomalies which are inevitably mixed, with these results. Though these anomalies are very trifling, they are, how- ever, so sepsible, and so frequently oceur, that they cannot e aseribed entirely to errors mm the observations. It ap- pears more natural to ascribe them to the influence of local circumstances, and the particular attractions exercised by collections of ferrngineous matters, chains of mountains, or by the large masses of the continents. One of us, indeed, having this summer carried to the: Alps the magnetic needle employed in one of his late aérial excursions, he found that. its tendency to return to) the magnetic meridian was constantly stronger in these moun- tains than it was at Paris before his departure, and than it has been found since his return. This needle, which made at Paris §3°9° in 10 minutes of time, has varied in:the fol- lowing manner in the different placcs to which it was car ried: Number of oscillations in, Places of observation. ten minutes of time. Paris before his departure - 83°9 Turn - - - 87°2 On Mount Genéyre - 83°2 Grenoble ~ _- - 87°4 Lyons - - > 87'3 Geneva - - - 86°5.. Dijon 7 PS = $4°5 Paris, on his return , - 83°9 These experiments were made with the greatest care, con- Jointly with excellent observers, and always employing the saine watch verified by small pendulums, and taking the s : mean in different Latitudes. 233 mean tetms between several serieses*of observations, which always differed very little: from each other. It appears thence to result that the action of the Alps has a sensible influence on the intensity of the magnetic force. M..Hum- boldt observed analogous effects at the bottom of the F»- renecs; for example, at Perpignan. It is not improbable that they arose from the mass of these mountains, or the ferrugineous matters contained in them ; but whatever may be the cause, it is seen by these examples that the general action of terrestrial magnetism is ‘sensibly modified by local circumstances, the differences of which may be perceived in places very little distant from each other. This truth will be further confirmed by the rest of this memoir. It is to causes of this kind, no doubt, that we must ascribe the diminution of the magnetic forces observed in ' some mountains ; a diminution which, on the first view, might appear contrary to the results obtained during the fast aénial voyages. This conjecture is supported by several ob- servations of M, Humboldt. Bymaking his needle to oscil- Jate on the mountain of Guadaloupe, which rises 676 metres (338 toiscs) above Santa-Fé, he found it in 10 minutes of time give two oscillations less than in the plain. At Silla, near Caracas, at the height of 2632 metres (1316 toises) above the coast, the diminution went so far as five oscillations ; and, on the other hand, on the voleano of Antisana, at the height of 4934 metres (2467 toises), the number of oscilla- tions in 10 minutes was 230; though at Quito it was only 218: which indicates. an imcrease of Intensity. I observed, indeed, a similar effect on the summit of Mount Genévre, at the height of 1600 or 1800 metres (8 or 900 toises), as may be seen by the numbers which I have already given; and it was on this mountain that I found the greatest in- tensity of the magnetic force. T saw on the hill of La Su- perga, inthe neighbourhood of Turin, an example of these variations equally striking. Observing, with Vassali, on this hill, at the elevation of about 600 metres (300 toises), we found 87 oscillations in 10 minutes of time. On the side of the hill we had 88-8 oscillations; and at the bot- tom, on the hank of the Po, we obtained 67-3. Though these results approach very ncar to each other, their differ- ence is, however, sensible, and fully shows that their small variations must be considered as slight anomalies produced by local circumstances. This examination leads us to consider the intensity of magnetism on the different points of the surface of the globe, as subject to two sorts of differences, Ont kind ame gencral : 54 Variations of the Terrestrial Magnetism general: they depend merely on the situation of the places in regard to the magnetic equator, and belong to a general phenomenon, which is the increase of the intensity of the magnetic forces in proportion as we remove from the equa- ter: the other kind of variations, which are much smaller and altogether irregular, seemto dependentirely on local cir- cumstances, and modify either more or less the general results. If we consider terrestrial magnetism as the effect of an attractive force inherent in all the material particles of the globe, or only in some of these particles, which we are far from determining, the general law will be, the total result of the system of attraction of all the particles, and the small anomalies will be produced by the particular attractions of the partial systems of the magnetic molecule diffused irre- gularly around each point; attractions rendered more sen- sible by the diminution of distance. It now remains to consider the inclination of the mags netic needle in regard to the horizontal plane. It has long been known that this mclination 1s not every where the same: in the northern hemisphere the needle inclines to- wards thenorth; in the southern towards the south ; the places where it becomes horizontal form the magnetic equator; and those where the inclination is equal, but not null, form on each side of that equator curved lines, to which the name of magnetic parallels has been given from their analogy to the terrestrial parallels. One may see in several works, and particularly in that of Lemonnier, entitled Lois du Mag- netism, the figure of these parallels and their disposition on the face of the earth. It evidently results from this disposition that the inclina- tion increases in proportion as we recede from the magnetic equator; but the law which it follows in its increase has hot yet, as far as appears to us, been given. To ascertain this law, however, would be of great utility; for the in- clination seems to be the niost constant of all the magnetic phenomena, and it exhibits much fewer anomalies than the. intensity. Besides, if anyrule, well confirmed, could be dis- covered on this subject, it might be employed with advan- tage at sea to determine the latitude when the weather does not admit an observation of the sun; which is the case in various places during the greater part of the year. We have some reason to expect this application when we see the delicacy of that indication in the observations of . M. Humboldt, where we find 0-65° (35’ 6”) of difference between two towns so near each other as Nismes and Mont- pellier. These motives have induced us to study with great . interest in different Latitudes. a55_ interest the series of observations made by M. Humboldt in regard to the inclination; and it appears to us that they may be represented very exactly by a mathematical hypo- thesis; to which we are far from attaching any reality in itself, but which we offer merely as a commodious and sure mode of connecting the results. To discover this law, we must first exactly determine the position of the magnetic equator, which is as an interme- diate line between the northern and the southern inclina- tions. For this purpose we have the advantage of being able to compare two direct observations; one of Lapey- rouse, and the other of M. Humboldt. The tormer found the magnetic equator on the coasts of Brasil at 12-1666? (10° 57’) of south latitude, and 28°2407° (25° 25’) of west longitude, counted from the meridian of Paris. The latter found the same equator in Peru at 7*7963° (7° 1’) of south latitude, and 89°6481° (80° 41’) of west longitude, also reckoned from the same meridian. These data are sufi~ cient to calculate the position of the magnetic equator, sup- posing it to be a great circle of the terrestrial Sphere; an hypothesis which appears to be conformable to observa- tions. The inclination of this plane to the terrestrial equator is thus found to be equal to 11-0247° (10° 58’ 56”), and its occidental node on that equator is at 133°3719° (120° 2’ 5”) west from Paris, which places it a little beyond the continent of America, near the Gallipagos, in the South Sea; the other node is at 66°-6281° (59° 57’ 55”) to the east of Paris, which places it im the Indian;Seas*. We * To calculate this position let NEE (Plate V. fic. 2.) be the terrestrial equator; NHL the magnetic equator, supposed also to bea great circle; and HL the two points of that equator, observed by Messrs. Humboldt and Lapeyrouse. Thelatitudes HE, LE’, and the arc EE’, which is the diffe- rence of longitude of these two points, is known: consequently, if we sup- pose HE =U, LE! =U’, EE/ =v, EN-= 2, and the angle ENH =y, we shall have two spherical triangles NEH, NE’L, which will give the twe following equations: ‘ tang. l cot y tang. 4! cot. y Sin. @ = sin. (2@ + v) = Gir) 5 from which we deduce (a + v) tang. LU ) 4 Mae. tangad and developing tang. Df cos. v cot. 2. = 2 tang. & sin. v sin. vu Let us now take an auxiliary angle p, so that we may have Pe tang. & sin. v ng. ¢ = ———_——-—. &? tang. L/ 256 Variations of the Terrestrial Magnetism We do not give this determination as rigorously exact : some corrections might no doubt be made to it, had we a greater. number of observations equally precise; but we are of opinion that these corrections would be very small; and it will be seen hereafter that, independently of the confidence which the two observations we have em- ployed deserve, we have other reasons for entertaining this opinion *. Bib? It is very remarkable that this determination of the mag- netic equator agrees almost perfectly with that given long avo by Wilke and Lemonnier. The Jatter in particular, who for want of direct observations had discusséd a great number of corresponding observations, indicates the mag- netic equator in Peru towards 7°3 of south latitude; and M. Humboldt found it in the same place at 7:7963° (7° 1’); besides, Lemonnier’s chart, as well as that of M. Wilke, indicates for the inclination of the magnetic meridian 12°22° (about 11°), and they place the node about 155° 56’ (140% of west longitude, reckoned from the meridian of Paris. Can it be by chance, then, that these elements, found more than 40 years ago, should accord so well with ours founded on recent observations? or does the inclination of the magnetic equator experience only very small variations, while all the other symptoms of terrestrial magnetism change so rapidly? We should not be far from admitting the latter opinion, when we consider that the inclination of ‘the magnetic needle has changed at Paris 3° during 60 years since it has been observed; and that at London, according to the observations of Mr. Graham, it has not changed 2° in 200 years; while the declination bas varied more than 20° in the same interval, and has passed from east to west : but, on the other hand, the observation of the inclination is so difficult to be made with exactness, and it is so short a time since the art of measuring it with precision was known, and we shall have ie ; sin. ? sin. > tang. 2 = ————_— , sin. (v — By these equations we may find a, and then y, by any of the first two. * Since this memoir was read, we have collected new information which. - confirms these first results. Lapeyrouse, after having doubled Cape Horn, fell in a second time with the magnetic equator in 18’ north lat. and 119° 7 of longitude west from Paris. He was therefore very near the node of the magnetic equator, such as we have deduced it from observations. ‘This fact establishes in a positive manner two important eonsequences: first, that the preceding determinations require only very slight corrections ; and the second, that the magnetic equator is really a great circle of the earth, if not exactly at least very nearly —ote of the Autiors, that Account of a Case of Hydrophobia. 257. that it is perhaps more prudent to abstain from any prema~ ture opinion on pbsenomena the cause of which is totally unknown to us. To employ the other observations of M. Humboldt in re- gard to the inclination, I first reduced the terrestrial latitudes and longitudes reckoned from the magnetic equator. ‘The latter, being reckoned from the node of that equator in the South Sea, I could first perceive by these calculations that the position of that plane determined by our preceding re- searches was pretty exact; for some of the places, such as Santa-Fé and Javita, where M. Humboldt observed incli- nations almost equal, were found nearly on the magnetic parallel, though distant from each other more than 6-6666° (6°) in longitude *. When these reductions were made, I endeavoured to re- present the signs of the inclinations observed, and to leave as little to chance as possible. I first tried a mathematical hypothesis conformable enough to the idea which has hie therto been entertained in regard to terrestrial magnetism. I have supposed in the axis of the magnetic equator, and at an equal distance from the centre of the earth, two cen- tres of attractive forces, the one austral and the other boreal, in such a manner as to represent the two opposite magnetic poles of the earth: [ then calculated the effect which ought to result from the action of these centres in any point of the surface of the carth, making their attractive force recipro- cally vary as the square of the distance; and in this manner I obtained the direction of the result of their forces, which ought to be that also of the magnetic needle in that latitude. - [To be continued.] XXXVIIL. Account of a Case of Hydrophobia successfully treated by copious Bleeding and Mercury. In two Let- ters from Dr. Rogert Burton, of Bent, in the State of Virginia, to Dr. Bensamin Rusu, of Philadelphiat. SO. llr Beuivine that you are always disposed. to, encourage any thing which may throw light upon the treatment of diseases, I take the liberty of addressing to, you the follow- * ‘This confirms what we have already said, that the magnetic equator i3 sensibly a great circle of the earth.—Note of the Authors, + From the American Medical Repository. Vol. 22. No. 87. dugust 1805. R jog _ ; ; 258 Accotint of a Case of Hydrophobia. ing case of hydrophobia, requesting a line or two, if you think it deserving your attention. On July 4, 1803, at nine o’clock in the evening, Iwas desired to visit Thomas Brothers, aged 28 years. I was informed by the person who came for me, that he had been bitten by a dog, which his friends suspected to be mad. 1 found him in the hands of four young men, who were en- deavouring to confine him, and thereby prevent him from injuring himself or friends. He recognised me, and re- quested me to give him my hand, which he made a violent effort to draw within his mouth. Conscious of his inclina- tion to bite, he advised his friends to keep at a distance, mentioning that a mad dog had bitten him. . His symptoms were as follow: viz. a dull pam in his head, watery eyes, dull aspect, stricture and heaviness at the breast, and a high fever. : Believing, as you do, that there is but one fever, I de- termined to treat this case as an inflammatory fever. I therefore drew twenty ounces of blood; and, as he refused to take any thing aqueous, I had him drenched with a large dose of calomel and jalap. ; July 5th, four a.m. Finding the symptoms worse, T took away sixteen ounces of blood, and applied two large epi- spastic plasters to his legs, hoping thereby to relieve the op- pression of the pracordia and other symptoms. Twelve m. Was informed that one of his friends had permitted him to take a stick in his mouth, which he bit so as to loosen several of his teeth. As he craved some- thing to bite, I desired his friend to give him a piece of lead, which he bit until he almost exhausted his strength. One p.m. Finding but little alteration, I drew eighteen ounces of blood, and had him drenched with the antimo- nial powders. Two p.m. He slept until half after three, when he awoke, with the disposition to bite, oppression, &c., but not so violent. July 6th, eight a.m. Found him biting the bed-clothes; his countenance maniacal, bis pulse synocha, with a stric- ture of the breast, difficult deglutition, laborious breathing, and a discharge of saliva. I took away twenty-four ounces of blood, gave him’ a dose of calomel and jalap, and con- tinued the powders. Twelve m. Drew sixteen ounces of blood, and gaye him landanum. Five Account of a Case of Hydrophobia. 259 Five p.m. Found him in a slumber ; his skin moist, and his fever and other symptoms much abated. July 7th, eight a.m. Was informed that he had only two paroxysms during my absence, and that he had lost sixteen ounces of blood agreeably to directions. Notwith- standing the favourable aspect which the disease wore, I tesolved to bleed him twice more, and then to induce an artificial fever by mercury, which would predominate over the hydrophobic. I therefore drew ten ounces of blood, and requested his friend to take eighteen ounces at night ; to rub in a small quantity of mercurial omtment, and to give a mercurial pill every four hours. : July sth, nine a.m. Found bim convalescent, but con- tinued the mercurial unction and pills. July 9th, ten a.m. Found his gums sore, and discon- tinued the mercury, July 15th, one p.m. Found him well, but with a con- siderable degree of debility. It would be doing injustice to you not to mention that T was indebted to your lectures for the successful treatment of this disease. August 21, 1803. —— To Dr. Burton. DEAR STR, Accept of my congratulations upon your rare triumph over a case of hydrophobia.. I give you great credit for the holdness of your practice. You have deserved well of the profession of medicine. In order to render your communication more satisfac- tory, permit me to request your answer to the following questions: 1. On what part of the body of your patient was the wound inflicted ; and how long was the interval: between the time of his being bitten and the attack of his fever ? 2. Did he discover any aversion from the sight of water? and did he refuse to swallow liquids of all kinds? 3. What were the appearances of the blood drawn? Did it differ in the different stages of the disease? Your answer to the above questions will much oblige your sincere friend, Philadelphia, ; y* BENJAMIN Rusu. Angust 29, 1809. 260 ~ Speedy) Decomposition of Water. To Dr. Benjamin Rush. SIR, ., | | T regret that business of an indispensable nature pre+ vented me from being more particular in my communica- tion. I drew it up ina hurry, intending to, transcribe at, and insert such other notes as would: throw light on the case; but being called out a few hours before the post set out from this place, I was, obliged to forward the commu- nication in the manner in which you receivedit.. 6. bos The part of the body of my patient on which.the wound was inflicted was a little above the union of the solzeus and gastrocnemius muscles, which form the tendo-achillis. The interval between the time of his being \yitten and the attack of the fever was twenty-four days. He was, I was told, dull and solitary a few days previous to the attack., A few minutes, before it, his friends tound him two hundred yards from the house, apparently.in a deep study. He has informed me, since his recovery, that he had a slight pain in the wound, attended with itching, and an uneasiness in the inguinal gland, several days before the fever. . He refused to swallow liquids, and the sight of water” threw him into a convulsive agitation. With regard to the appearances of the blood-drawn, I am sorry to inform you, that after it became cold I did not examine it, rah Tam, sir, yours, &c. Bent Creek, Virginia, *"RoBERT BuRTON. September 18, 1803. I XXXIX.: Hints respecting a speedy Decomposition of Water by Means of Galuanism. _ By Mr. Witu1am Witsony To Mr. Tulloch. is SIR, segue London, August 22, 1805. Ay a time like the present, when there is every appear- ance of some importatt discoveries in chemistry being madé by the ‘help‘of Galvanism, “any-experimént connected with this subject that is not generally known {atid especially. such as relate to the décomposition of water, and that4n amore rapid manner than is usually done by Galyanism) must be - acceptable to persons engaged in this branch of seience. I therefore take the liberty of troubling you with the follow- , I si ng - “by means of Galvanism. 261 ini¢ accéunt of some experiments T made, about a year and a half ago, with a Galvanic frough containing fifty pair of plates four inches square. If yout think it worthy of.a place m your Philosophical Magazine, you will insert it therein. Being desirous of ascertaining whether water would be decomposed or no, if the wires, which were connected with the ends of the trough, were at a considerable distance from one another, I inserted two short silver wires through corks mto the ends of a class tube 36 inches long, and w hich was filled with water: the ends of the wires were about 34 inches asunder, which distance was too great for any visible de- composition of the water to take place ; yet that wire which was connected with the zine end of the trough, gave a very faint whitish cloud which descended *. Witha shor ter tube the decomposition of the water eames when the ends of the wires were at the distance of 18 inches. It then struck me, that if a wire was interposed between the two end wires.of the long tube a decomposition might possibly be effected at two places i in the tube at the same time, and that the quantity of as evolved would be greater than if it was evolved at only one place. I therefore introduced a piece of iron wire between the end wires, in such a manner that its ends came within an inch of them. When acom- munication was made with the trough there was a very copious evolution of gas at both ends of the interposed wire, and at that end wire that was connected with the copper end of the trough 5 : and a red oxide of iron was ferme at one end of the iron wire, while a black oxide was formed at the other. To try if any increased effect would take place if there was a greater surface of the wires o pposed to one another, I pushed the end wires further into “the tube till their ends passed about an inch beyond the ends of the interposed wire: when a communication was made between them and the ends of the trough, a very rapid evolution of gas took place throughout the whole éxtent of the parts of the wires that were opposed. ~ Finding the quantity of gas much increased by this ma- nagement, [introduced a wire into each end of a tube about 16 inches long. Each of these wires passed nearly the whole length of the take without touching one another, so that the length of the opposed parts was 14inches, When these were connected with the trough, there was a very co- * Witha battery of troughs containing 490 pair of plates 4 inches square, the decomposition took place when the wires were withdrawn to the ends of the tube, Ra pious 262 Observations on Volcanoes and their Lava. pious evolution of gas through the whole length of the tube, The wires used in this were iron, and the red and black oxides were formed in considerable quantity. Seeing the quantity of gas evolved with a given power is in proportion to the quantity of surface of the wires oppo- sed, many contrivances might be used to increase the effect to a considerable degree. If thin plates of metal were used instead of wires, a greater surface would be opposed, and in all probability the effect would be increased. Several wires or plates might be arranged im the same tube, and alternately connected with the ends of the trough; or, if wire cloth was used instead of plates, probably the effect would be still further increased. T am, sir, your obedient humble servant, WiILLiAM WILson; . XL. New Observations on Volcanoes and their Lava. By G.. A. DELUc*. V otcanozs have been so numerous on the surface of our continents, when they were under the waters of the antient sea; and as this class of mountains, raised by sub- terranean fires, manifest themselves still on the shores of the present sea, and in the middle of its waters, it is of importance to geology and the philosophy of the earth to obtain as just ideas of them as possible. I have attended a great deal to this subject from my own, observations; and 1 have shown, at different times, the errors into which several geologists and naturalists, in ireating of it, have fallen, NAY | This class of mountains, in particular, requires that we should see them, that we should behold them during their eruptions, that we should have traced the progress of their lava, and have observed closely their explosions ; that we should have made a numerous collection of ‘the matters. which they throw up under their different circumstances, that we might afterwards bé able to study them in the ca- binet, and to judge of their composition according to the phenomena which have been observed on the spot. This study is highly necessary when we apply to geology and the philosophy of the earth, in order that we may avoid falling into those mistakes which make us ascribe to sub- terranean fires what does not belong to them, or which leads us to refuse them what really belongs to them. : * From Journal de Mines, Vhermidor, An. xii, No. 95. We / Observations on Volcanoes and their Lava. 263 We read in the Journal de Physique for January, 1804, » under the title, On the cause of Volcanoes, the following assertions : «© What: is the nature of the matters which maintain these subterranean fires?) We have seen that Chimboraco, all these enormous volcanoes of Peru, and the Peak of Teneriffe, are composed of porphyry. ‘ traveller; written’ from Mexico, on his return from Peru, where, speaking of the voleanoes, of Popayan, Pasto, Quito, and the other parts of the Andés, he says, ‘*/Great masses of this fossil (obsidian) have issued fron» the craters ; and the sides of these gulphs, which we closely examined, consist of porphyry, the base of which holds a mean between obsidian and pitch-stone (pechstein).”” M. Humboldt therefore considers obsidian, or black compact glass, as a natural fossil or rock, and not as volcanic glass. Father dela Torre; who resided at Naples, and has written on, Vesuvius, believed also that the interior of its: mouth §vas composed of natural rocks. and strata like, every other : No. 17, . " mountain: 270 Olservations on Volcanoes and their Lava. mountain: he calls them strati naturali, sassi naturali, though every thing there be the work of fire. If M. Humboldt had been a witness to the birth and formation of the craters of which he speaks, he would soon have given them up entirely to the volcanic empire. The violence of the fire; the explosions and burning lava with which that empire would have reclaimed them, would soon have silenced all Neptuntan pretension, and confirmed that these masses, which he calls porphyry, and their bases, holding a medium between obsidian and pitch-stone, are lava and vitrifications belonging to Vulcan. M. Humboldt derives his objection against the opinion that obsidian is yolcanic glass, from its swelling up and becoming spongy and fibrous by the least deerce of heat of a furnace, whence he concludes that if cannot be the production of fire. An attentive examination of volcanic productions shows that their state and appearance depend on the nature of the matters which have been subjected to the action of the fires, on the degree of heat, the time and place where it has been exercised. Therefore a degree of heat which has been able to reduce any substance to compact glass, would not. be sufficient to put it into a state of ebullition, and at that moment could not be carried to a degree capable of pro- ducing that effect: to this the want of free air may contri- bute. But there are some circumstances, even pretty fre- quent, of volcanic fires giving fibrous and puffed-up glass. I possess a vitrification from Lipari, the centre of which is compact vlass, and the inside im lamina, bubbles, and threads, like pumice-stone. I have in my possession an- other, part of which is glass nearly compact, and part glass very much puffed up. I found on the sea-shore, near Messina, two pieces of four or five inches in diameter, formed merely of vitreous lamine, elongated, undulated, and full of puffed up places. I have two fragments. of obsidian, or black compact glass of Ischia, one of the en- tire faces of which evidently shows by the circular undula- tions of the one, and the rounded inequalities of the other, that they have been in a state of fusion. I saw at Vuleano a vitreous mass, from which I broke a large fragment, the glass of which is compact in some parts, and full of puffed up places, some of them latge and others small. Of this kind is the black compact glass of the volcanoes of Iceland. Another objection of M. Humboldt is, that obsidian is found in’such large masses that it may be compared to a quarry. But why should this be an objection? Vitreous lava does not differ from any other lava, but by more perfect Wdinkd vitrification ; Royal Society of London. $71 Vitrification ; and in regard to the size of the masses, it may be said that it has no bounds, since Aitna, a volcano much less considerable than those of Peru, throws up lava several leagues in extent, and of a very great thickness. Obsidian, therefore, or the black glass of the volcanoes of Peru, is as certainly a production of their fires as the lava which is seen to issue from the bottom of every crater. [To be continued.]} XLI. Proceedings of Learned Societies. ROYAL SOCIETY OF LONDON, Tx the sitting of 25th April last there was read an inte- resting paper on an artificial substance possessing the prin- cipal characteristic properties of tannin, by Charles Hat- chett, Esq. a member of the society. «| The author, after mentioning the labours of Mr. Deyeux and Mr. Seguin, the former of whom first separated this substance from galls, the characteristic property of which, to precipitate gelatin from water, was ascertained by the latter; and after phair) experiments of Mr. Big- gin, Mr. Proust, and Mr. Davy, remarks that no one had hitherto supposed that it could be produced by art, uniess the fact mentioned by Mr. Chenevix, that ‘* a decoction of coffee berries did not precipitate gelatine, unless they had been previously roasted,’’ might be considered as an indi- cation of it. Recent experiments have, however, shown him that tannin may be formed by very simple means, not only from vegetable, but from mineral and animal sub- stances. In the course of his experiments on lac and resins, he observed the powerful effects of nitric acid on these sub- stances, and has since observed that by long digestion almost every species of resin is dissolved, and so completely altered that water does not cause any precipitation, and that by evaporation a deep yellow viscid substance is obtained, equally soluble in water and in alcohol. In his experi- ments afterwards, on the bitumens, he observed a material difference between their solutions and those of resins. With bitumens, nitric acid, by long digestion, formed a dark brown solution ; a deep yellow coloured mass _ was se- parated, which, by subsequent digestion in another portion of nitric acid, was completely dissolyed, and, by evapora- tion, ‘ ‘ 2 - Royal Society of London. tion, was converted into a yellow viscid substance similar to that obtained from the resins. Mr. Hatchett therefore concluded that the dark brown solution was formed by the action of the nitric acid on the uncombined carbon. of the bitumens; that the deep yellow portion constituted the essential part of the bitumens; and therefore that the dark solution was in fact dissolved coal. He accordingly tried pit coal, and, by a similar treatment, obtained the same dark brown solution in great abundance, but not when he used coals which contained little or no bitumen. Having by means of nitric. acid obtained solutions from asphaltum, from jet, pit coals, and charcoal, he evaporated each to dryness, very slowly, to expel the remaining acid without burning the restduum, which in each was a glossy brown substance, exhibiting a resinous fracture, soluble in water and-in alcohol, and highly astringent. Exposed to heat, they smoked but little, swelled, and yielded a bulky coal. Their solutions reddened litmus paper, and precipi- tated various metallic and earthy, salts, and also glue or isinglass, yielding a precipitate msoluble in water, cither hot. or cold—and consequently possessing all the properties of tannin, uncontaminated with gallic acid. Mr. Hatchett then reduced some animal substances to the state of charcoal, and, by a treatment similar to the above obtained from them tannin. -— Some kinds of coal, which in their natural state yielded little or no tannin, on being brought to a red heat in a close vessel, and then digested with nitric acid, were almost _wholly converted into that substance... The result was the same with various kinds. of wood ;—when charred they yielded a great quantity of tannin, though before under- going that process they would yield none. This ingenious paper contains other interesting details on matters connected with this subject, all tending to show that different substances yielded tannin in proportion to the quantity of their original carbon, and that substances re- duced into coal in the humid way (as by the action of sulphuric acid) in like maner yield the tanning substance by nitric acid; but we shall not enter more into this detail till the paper itself be published. On the 4th of July was read, a paper by W. Hyde Wol- laston, M.D. on the discovery of palladium; with ob- servations on other substances found with platina. The author, having purified a great quantity of platina by precipitation, had an opportunity of examining the various impurities usually) mixed with. the eres his ae F Royal Society of London. 273 This led him to the discovery of the new metal which he named rhodium, and also to the discovery which forms the principal subject of this paper. He mentions also having found blended with platina the ore of another metal, which has hitherto passed unobserved from its great resemblance to the grains of that metal. These grains he considers as the ore of iridium, the new metal discovered by Mr. Ten- nant. They are insoluble in nitro-muriatic acid, are harder than platina, brittle under the hammer, and break with a laminated fracture. Mr. Tennant has undertaken the ana- lysis of a portion of this ore. The author mentions having separated from the ore of platina, by a current of water, some very minute red cry- stals, the quantity of which was too small to admit of ana- lysis; but from such an examination as he could give them he conciudes them to be hyacinths. Having separated these and other impurities from the ere of platina, as far as practicable by mechanical means, dissolved the ore, and obtained, in the form of a yellow triple salt, all the platina that could be precipitated by sal- ammoniac, clean bars of iron were used to separate the re- maining platina. This precipitate, consisting of various metals, was subjected again to exactly the same treatment, when the precipitate obtained by sal-ammoniac was found to be not of so pale a yellow as before: bars of iron were also again used to precipitate what remained suspended. A repetition of the same process on this second precipitate led to the discovery of palladium ; tor Dr, Wollaston found that a portion of if resisted the action of the nitro-muriatic acid, though this powder had been twice completely dis- solved before. The solution was very dark in colour, yielded by sal-ammoniac only a small quantity of precipitate, and, instead of becoming pale by the precipitation of the platina, retained the dark colour which it had acquired from the other metals held in solution. The second metallic preci- pitate, therefore, became the subject of investigation. Lead, iron, and copper, were detected iu it by muriatic acid. Di- Jute nitrous acid separated a further portion of copper, form- ing, as usual, a blue solution; but when a stronger acid was used for the purpose of separating the remaining cop- per, the dark brown colour of the solution gave evidence that some other metal had been dissolved. A small portion of the solution was put on a surface of platina; and on ap- ies a clean plateyof copper a black precipitate was “4 tained, soluble in nitric acid, and consequently neither gold nor platina. The solution in that acid was red, therefore the metal was neither silver nor mercury; and having been Vol. 22, No. 87. dugust 1805. S$ precipitated 274 French National Institute. precipitated by copper, it was none of the other knowtf metals. Mercury, agitated in a warm nitrous solution of this metal, acquired the consistence of an amalgam, which when exposed to a red heat left a white metal—palladium ; which gave a red solution, as before, with nitrous acid, could not be precipitated by sal-ammoniac or by nitre, but yielded a yellow precipitate with prussiate of potash, and in the order of its affinities was precipitated by mercury, but not by silver. The author, however, adopted afterwards another process for obtaining palladium, depending on one of its most distinguishing properties, by means of which it may be obtained with the utmost facility. To a solution of crude platina, whether neutralized by evaporation of the redundant acid, or saturated by any of the alkalies, by lime or by magnesia, by mercury, copper, or iron, and also whe- ther the platina has or has not been precipitated from it by sal-ammoniac, it is only necessary for the separation of the palladium that prussiate of mercury be added to the solu- tion. Ina short time it beeomes turbid, and a flocculent precipitate is gradually formed of a pale yellowish white colour. The prussiate of palladium thus obtained, when heated, yields that metal in a pure state. FRENCH NATIONALE INSTITUTE. On the 23d of June the first class of the French Nationa! Institute, that of the Mathematical and Physical Sciences, held a public sitting, when the following papers were read : Ist, Chaptal’s report on the prize question respecting the winter sleep of animals, 2d, Delambre’s eulogy of P. F. A. Mechain. 3d, Memoir of Pinel on the treatment of lunatics in & large hospital, and on the result of three years’ experience at the Salpetriere. 4th, Memoir on the terrestrial magnetism, by Biot. 5th, Jussieu’s account respecting the last voyage of dis- covery. 6th, Cuvier’s eulogy on Dr. Priestley. The prizes also were adjudged for the papers on the last prize questions. An Account of the Labours of the Class of the Mathema- tical and Physical Sciences of the French National Insti- tute from the 20th of June 1804 to the same Dey 1805. By M. Cuvier, perpetual Secretary. {Continued fram p. 178.} We have in commerce three kinds of strong glue, those ef England, Flanders, and Paris. The first, is the best, and: 8 the French National Institute. o75 the third the worst. M. Seguin, having accurately com- pared their degrees of goodness, that is to say, of tenacity, has examined the difference of their chemical principles. He has always found in the glue of Paris an insoluble mix- ture of gelatine and calcareous soap, which 1s deposited when the glue is dissolved: in that of Flanders, a coagu- lated albumen, which deposits itself also: that of England alone is free from this mixture and deposit. Nothing re- mained but to discovera sure method of making glue si- milar to that of England. M. Seguin first saw, that of all the animal parts capable of giving glue, skins furnish the best, aad particularly the skins of adult animals killed by the butchers. He then saw that every thing depends on the method of freeing them from the hair. The worst glue is produced by skins freed from the hair by lime; that of skins freed from the hair by alkalies is a little better ; but the most tenacious is obtained from skins freed from the hair by gallin, and particularly by the successive action of gallin and diluted sulphuric acid. But gallin is rare, and too dear for such an application. M. Seguin, therefore, did not obtain a complete solution of the problem which he proposed, but by finding out a substitute for gallin, which is moistened malt. The name of degras is given to a matter employed for currying leather, and which is obtained in the preparation of shammy leather. There are twe kinds of it} that of the country and that of Niort, which is better and dearer than the former. The degras of the country, according to Seguin, is composed of oxygenated oil, soap, and gelatin in particular states. The two latter principles hurt its ef+ fect. The degras of Niort contains none of these sub- stances, and is only oil im a certain state. M. Seguin imi- tates it, the colour excepted, by treating oils with nitric acid; and the product he obtains proves a substitute, at less expense, for the degras of Niort. M. Sage has shown us some singular products of the chemieal art in foreign countries. The Chinese make fur- naces which are as light as pasteboard, and which are in- combustible, because they are made of amianthus. The same nation employ zinc for coin, a semi-metal which did not seem proper for such a purpose. The same chemist continues, with indefatigable ardour, to describe those ob- jects interesting to geology which are contained im his col4 lection. He has showty us this year several euttious fossils belonging, for the most part, to the class of shé}ls, such as terebratuls, orthoceratites, nummiularia, &e. — Se The 276 French National Institute. The voyage of M. Peron, among the infinite number of interesting objects it has procured, has furnished us with two proper for throwing light on the history of these fossils. The shell called by naturalists nawéilus spirula was among those still found alive the nearest to the cornua ammonis, the spiral camerines,-and nummularia. M. Peron brought home the animal, and we have seen that it is not contained in the shell, but, on the contrary, that it contains the shell, as the cuttle-fish contains its bone. This animal belongs, therefore, to the genus of the cuttle-fish. It gives us reason to believe that the cornwza ammonis and nummularia belong to it also, and he explains every thing that remained em- barrassing on this subject. The same traveller has brought back also an animal near a-kin to the medusz, which con- tains in its inside a cartilaginous disk entirely analogous in its structure to the concentric nummularia. M. Sage ob- served in a piece of coal the impression of a disk, which must have resembled that of this medusa still more than these nummiularia themselves. M. Cuvier, who has made known to the class these two results of M. Peron’s collections, presented to it also two facts interesting to geology, discovered by himself. The first is, that among the numerous animals of un- known genera with the remains of which the plaster quar- ries in the neighbourhood of Paris are filled, there is found a kind of opossum, a genus still existing, but only in the new continent: the other is, that the remains of a hyena, very similar to that of the Cape of Good Hope, are scattered throughout the earth in different parts of France and Ger- many. : M. Desmarets has contributed also to extend this curious part of the natural history of animals known only by their remains. He has presented to us two sorte of fossi! shells of Angoumois hitherto unknown to naturalists : he has read to us also.a treatise on the different sorts of vegetable earth, their characters, and their origm. We have had like- wise in mineralogy a Description of Guadaloupe by M. l’Escalier. This island is in part volcanic and in part madreporic. M. Humboldt has given us ayview of the geologic com- position of the heights of the Cordilleras. M. Ramond has added new observations to those. which he before made on the Pyrenees. M. Lelievre has taught us that the kind of mineral called pinite has been discovered in France by Cordier, who found It in minerals collected in the environs of Clermont in Au- ; vergne, ~ _* French National Institute. 277 vergne, by M. Lecoq, commissioner of gunpowder. Hi- therto it has been found only in Saxony. ; Botany continues to be enriched with an increasing num- ber of new species. The superb work on the Jardin de Mal- maison, by M. Ventenat; the Flora of the Oware of Benin, by M. de Beauvois; that of the Isles de France et dé Bour- lon, by M. du Petit Thouars; that of New Holland, by M. de Bellardiere, are prosecuted with saccess. Messrs. de Humboldt and Bonpland haye published the first number of that of South America. M. Desfontaines has published a catalogue of all the ve- getables in the Jardin des Plantes; a valuable work, not only for those who frequent that celebrated school, but also for all botanists. M. Broussonet has also given that of the Jardin de Montpellier. Botany for a long time has been accustomed to honour those who cultivate and patronize it, by giving their names to the new genera it discovers ; and experience has proved that such monuments are the most durable of all. No person deserved this honour more than the empress, who takes so much pleasure in that agreeable science, and who promotes its progress so much. The Spanish bota- mists, Messrs. Ruiz and Pavon, had already paid her this honour by giving the name of her family to a beautiful plant of South America. M. Ventenat, charged by her majesty with making known to the pubiic all the new species of the garden of Malmaison, has consecrated to her a second, the Josephina, originally from New Holland, and near a-kin to the digi- talia and the pedalia. The elevation of its stem and the beauty of its Howers will make it be cultivated in pleasure- gardens. M. de Beauvois has dedicated to the emperor Napoleon a tree of the country of Oware, in Africa, distinguished by its splendour, and the size and singularity of its flower. M. de Humboldt during his travels enriched the natural history of plants with general and very new considerations: he has traced out a sort of geography of them, in which he determines the limits of each species in latitude and in ver- tical height: it is the temperature which stops them in both directions ; but as the degrees which suit each are different, they extend more in breadth, or rise higher, on the moun- tains, according to this difference; which may serve as a sure guide to agriculture in the choice of the plants which it destines to each position. This indefatigable traveller has enriched no less the his- S3 tory 278 French National Institute. tory of animals. He has described several new species, among which we have to remark in particular one of the fish thrown up sometimes by the volcanoes in South Ame- rica. Do they live in subterranean lakes which have a communication with the sea? M. Peron has communicated to us two observations ex- ceedingly valuable in regard to the natural history of man. The first relates to the celebrated apron of the Hottentot wo- men; denied by some, and differently described by others. M. Peron proves that it is a natural excrescence, which: forms one of the characters of a particular race known under the name of the Boschmen. ‘The other observation relates to the strength of the savages. A number of expe- riments, made by Regnier’s dynamometer, has shown that they are sensibly weaker, c@ieris paribus, than the people of civilized nations. We long ago announced the celebrated work of Berthollet entitled Stateque Chimique. M. Pinel bas written another, the title of which is Statique Anatomique. We have an- other of the same kind written in the century before last by the celebrated Borelli; but mechanics and anatomy have both since that period made so much progress, that Borelli’s work, excellent for its time, is at present superannuated. A particular object of anatomy, namely, the teeth, has been long studied by M. Tenon. This profound anatomist _ has made so many discoveries on this subject,that it is more indebted to him than to any person who preceded him. He > has Jately read to us a memoir on a substance peculiar to the teeth of certain herbivorous animals, such as the horse and elephant, which envelops the enamel. The same physician has communicated to us a great work on diseases of the eyes, which he will soon publish, and another on the diseases peculiar to hatters. The latter arise ehiefly from the use which hatters make of mercury to ren- der common hair fit to be manufactured into felt, since we were deprived of beaver skins by the loss of Canada. These diseases cannot be prevented but by weakening as much as possible the mercurial liquor employed, or by endeavouring to discover some other kind of hair which may be converted into fe't without that liquor. M. Tenon has read to us also several memoirs on surgery, concerning the different methods hitherto used to prevent or correct those accidents which are inseparable from our nature. Of this kind are instruments proper for extirpating polypes of the nose; and a method, by compression, of stopping hemorrhages of the mouth. [To be continued. ] Vaccine Inoculation. 279 MEDICAL AND CHIRURGICAL SOCIETY OF LONDON. An institution has been lately established in London for the purpose of promoung a liberal and useful intercourse among the different branches o of affording a centre for f the medical profession, and the reception of communications, and for the formation of 2 select and extensive professional library. London, professional men of the first It is called the Medical and Chirurgical Society of and it comprises in it a considerable number of character. The meetings (which will commence in October) will be held at the So- ciety’s apartments, Verulam Buildings, Gray’s Inn, where any communications, or donations of books, are requested to be sent, directed to the Secretaries. The following is a list of the officers and council for the present year: President—W™m. Saunners, M.D. F.RS. John Abernethy, esq. F.R.S. vice-pres. Charles Rochemont Aikin, esq. sec. Wm. Babington, M.D. F.R.S. vice-pres. Mattthew Baillie, M.D. F.R.S. Thos. Bateman, M.D. F.LS. Gilbert Blane, M.D. F.R.S. Sir Wm. Blizard, F.R.S. vice-pres. John Cooke, M.D. F.A.S. vice-pres. Astley Cooper, esq. F.R.S. treas. James Curry, M.D. F.A.S. Sir Walter Farquhar, bart. M.D. Thompson Forster, esq. Algernon Frampton, M.D. John Heaviside, esq. F.R.S. Alex. Marcet, M.D. foreign secretary Dav. Pitcairne, M.D. F.R.S. Hen. Revell Reynolds, M.D. F.R.S. H. Leigh Thomas, esq. James Wilson, esq. F.R.S. John Yelloly, M.D. secre- tary. Se ee ee XLII, Intelligence and Miscellaneous Articles. VACCINE INOCULATION. Tur Aligemeine Literatur-Zeitung, of 24th of July, re- marks that it has been shown in some of the German publications on the cow-pock, jJation was known in German y that this method of inocu- before it was recommended by Dr. Jenner; and the case appears to be the same in France. M. Audouard of Castres, now at Paris, secretary to the society of the practice of medicine at Montpellier, has discovered that the method of vaccine inoculation was $4 practised 280 Vaccine Inoculation. practised in some of the departments of France long before the attempts of Dr. Jenner. M.Audouard will publish a work on this subject, in which it is expected he will give proofs that this method belon; gs originally to France.”” On this we may observe, that we have no doubt of the fact, for it was also practised in Beata by solitary individuals ; but this does not lessen at all the merit due to Dr. Jenner, who was the first to point out the proper use that might be made of the fact; nor of Drs. Pearson, Woodville, and others, who seconded his views, and have laboured with such in- cessant zeal to promote its general adoption, not only in this country, but in every part of the world—and with so much success, that at no very distant period we may expect to see the small-pox, the most dreadful scourge with which the human race were ever afflicted, banished from the face of the earth. . Ragusa, June 30th, The vaccine has at length been adopted at this place, owing to the exertions of that indefatigable physician Stulli, and the repeated instigations of Dr. de Carro of Vi- enna, to whom we are indebted for this benefit. Dr. de Carro’s Catechism on the Vaccine, translated into the Iilyric Janguage, and distributed in the town, and by the country clergymen, has contributed greatly to dispose the inhabi- tants for receiving it, The vaccine matter of Vienna has succeeded very well: in the course of a few weeks Stull has vaccinated a hundred children; a great many for this country, which in some late years, and particularly in 1802, lost a great many children by the natural small-pox. ‘This happy discovery is making great progress among the Dal- matians and Turks. Manheim, July 28th. According to the last accounts received by Dr. de Carro, at Vienna, respecting the progress of vaccination in the East Indies, the governor, by a public notice, dated Janu- ary 19, 1803, requested the F-uropeans and natives belonging to the presidency of Fort St. George to take advantage of this salutary discovery. It results from the official reports of the board of medicine, that from the 1st of September 1802 to the 30th of April 1804, there were inoculated with success 145,840 persons, namely 165 Europeans, 4,141 Bramins, 41,806 Malabarese, 40,022 Gentoos, 10,926 Ma- hometans, 444 of mixed casts, 1,092 Portuguese, 35,975 Parias, 440 Mahrattas, 10,367 Canaputes, 462 aa The Proposal for encouraging Vaccination. 281 The raja of Tanjore encourages vaccination as much as pos- sible, and the dewar of Travancore has himself submitted to it. PROPOSAL FOR ENCOURAGING THE PRACTICE OF VAC= CINATION. The great number of persons who have taken the small- pox in the present year shows plainly that so many have not been vaccinated as hath been represented. Indeed, we have long more than suspected that accounts given by many practitioners to the public of the number inoculated by each of them was not exact. A practitioner is too apt to assume consequence from the long list he produces, and this it is makes him apt to plume himself upon the credit given to him for the number rather than for the accu- raey and novelty of his observations; or itinduces him to strive to swell his list of number, rather than to bestow the labour of observation. Hence too it has happened that many persons have taken the smail-pox subsequently to the practice of such inexact inoculators for the cow-pock. It is decisive that the numbers given to the public are ex- ageerated, not only for the reason just set forth, but be- cause the total united sum from the different lists exceeds the sum en any reasonable calculation which the population affords to be inoculated. If we remove a cypher from the figures containing the numbers asserted, the sum remain- ing will be less remote from the most accurate calculation of the real number vaccinated : for instance, in some state- ments, instead of 10,000 say 1,000; tor 5,000 say 500, and sO in proportion. The late prevalence of the small-pox has not only Jed to the above remarks, but to the consideration of the means of rendering vaccination effectual for extinguishing the small-pox. Supposing that when the cow-pock is duly excited, a person has as great a chance of security as after due inoculation for the small-pox, it was announced at a public meeting—the annual one of the original Vaccine Pock Institution, Broad Street, on the 7th February 1803,— that a plan would be brought forward to show the necessity of laws for the inoculation of every subject within a cer- tain period after birth, as well as for the immediate prohi- bition of the inoculation of the small-pox. It was con- tended that the prohibition of the small-pox inoculation alone would be inadequate to the purpose of extinguishing the small-pox ; and it was maintained that it was not more "an infringement of the liberty of the subject to render the cow-pock 482 Proposal for encouraging Vaccination: eow-pock inoculation universal, than to prohibit, as already proposed, the small-pox inoculation*. The same gentle- man (Dr. Pearson) who made these observations, has lately explained to the Vaccine Tnstitution that he had been dis- couraged and induced to lay aside his plan, from the opi- nion of a great number of friends, who almost universally disapproved it as impracticable in the execution, and im- prudent for the author. He has accordingly lately pro- posed two things, by way of rendering vaccination less liable to failures, and more extensively practised. 1. That each person Inoculated at the Institution shall havea ticket signed by three members of the medical esta- blishment, attesting that the vaccination ‘has been duly un- dergone; and that if the person so attested shall subsequent- ly take the small-pox, such person shall be entitled to ten guineas from the Institution. g. It is proposed that the medical establishment shall erant certificates, which may have the effect of diplomas to qualify pupils, by attending the practice and lectures at the Institution. It is remarkable, and indeed singular, that notwithstand- ing the Institution has been established near six years, not a single authenticated case of small-pox subsequently to the cow-pock has occurred in the practice. Of the invculation of persons who have undergone the cow- pock 30 to 50 years ago; with some anecdoles of Farmer Jesty, ihe Vaccinator of his family in 1774. Mr. Benjamin Jesty, farmer, of Downshay, accompanied by his son Mr. Robert Jesty, lately visited the Vaccine Institution in Broad Street, where he proved, by authen~ tic evidence of various kinds— 1. That he took the cow-pock from his own cows about 50 years ago, and although he had been often in the way of the small-pox, he had remamed unsusceptible. He has a scar on one hand from the cow-pock. 2. That knowing many instances besides himself of persons never taking the small-pox who had taken the cow-pock in dairy farms; and that it was a harmless com- plaint; also being of opinion that he should avoid ingraft- mg diseases of human subjects, such as evil, lues, mad- . * See Philosophical Magazine, vol. xv, No. 57, p. 81. + The medical establishment consists of—Doctors Pearson, Nihell, and Nelson; Surgeons .extraordmary, Thomas Keate, Thomas Payne, and Thompson Foster, esquires; Surgeons in ordinary, John Gunning, J. C. Carpue, and J, Doratt, esquires; Visiting apothecaties, Francis Rivers, Augustus Brande, and P.de Bruyn, squires. ' nessy Proposal for encouraging Vaccination. 283 ness, &c., by inoculating from the cow, he determined to prefer vaccination in his own family. Accordingly, when the small-pox prevailed in the town and neighbourhood of Yetminster, in 1774, where he then lived, he inoculated his wife, Mrs. Jesty, and his two sons Robert and Benja- min, with matter from his cows. Benjamin showed a Jarge cicatrix, on the middle of the upper arm, left by this inoculation 31 years ago. The two sons were inoculated for the small-pox, without effect, 15 years ago; and they, as well as Mr. Jesty, have been often in contact with per- sons in the smail-pox in the course of 31 years. To give further satisfaction, Mr. Robert Jesty, without hesitation, agreed to the proposal of being again inoculated while in town for the small-pox. Accordingly variolous limpid matter was very carefully inserted by four punctured places in the left arm, immediately from a child in the 6th day of the erup- tion. Red pimples appeared in the punctured parts the day after inoculation, which continued for two or three days, and then died away without any attending pain of the arm or arm-pit, or any constitutional disorder. Mr. Jesty’s aversion to the small-pox “ humour,” as he called it, occasioned him to prefer being tested with vaccine matter. Accordingly he was inoculated in four places in one arm with matter immediately from a subject in the gth day of vaccination. The farmer described how much he was censured by his neighbours for inoculating his family from ‘‘a beest—a brute creature without any soul ;” and he was called ‘a hard-hearted man :”’ but he answered that the brutes were free from many disorders of men ; and he saw that “ there were many Christians who were greater brutes than the cows.” It_is worthy of notice, all the four parties in the cow- ock inoculation have enjoyed an uncommonly good state of health, and are all athletic subjects. Mr. Jesty, who is 70 years old, is a fresh-looking man, and has the usual ap- pearance of a man of five-and-fifty, or at the most of sixty. The indistinctness of his speech is from the lossrof all his teeth. To gratify the public, and to preserve for posterity this jnteresting part of the history of cow-pock inoculation, the Vaccine Institution have had a whole length picture of farmer Jesty painted by Mr. Sharp of Suftolk-street. It has been executed in a capitally successful manner ; but it must be owned that the manly figure and fine countenance’ of the subject were in favour of the ingenious artist. : BOTANY. 3 284 ‘ Botany. BOTANY. A private individual in the government of Asiracan, has semt to the Russian minister of the interior the roots and Jeaves of a plant which grows therein great abundance, to- gether with meal and bread prepared from these roots. The accompanying memoir states that these roots have been long used by the Calmucs as food; that the bread made ffom them is wholesome and well tasted ; that in case of a scarcity, occasioned by a bad crop, it might be employed as a good substitute for common bread, and that the plant is easily propagated by seed. Further examination has shown that this plant is nothing else than the dutomus umbellatus, Linn,; in English the flowering rush or water gladiole; in French butome a om- belle jonce fleuri; in Tartaric sussatok; in Ostiak russ; in Russian sussac, sotschnoj koren. It grows in every part of Europe, in Siberia, and in the neighbourhood of Peters- burgh, and particularly in marshes and rivers. The Cal- mucs roast the roots or dry them, and use them in that manner as food. According to the elder Gmelin, they are used aJso for the same purpose by the Ostiaks and neigh- bouring people. In former times a healing power was ascribed to this plant. Meal has been prepared at Petersburgh from the roots, and bread baked of ijt, Weare informed that the meal in kneading has all the properties of common meal, The dough rises very easily when leaven is added to it; and the bread is very little inferior in colour, taste, or smell, to wheaten bread; the only difference is, that it is not so tough, and readily breaks, in consequence of the fine fibres of the roots which’remain in it, and it has also a little bit- terness. From all these facts it appears that this plant may become. a substitute for corn; and if the bread be as wholesome as is asserted, this discovery deserves the utmost attention, and particularly in places which do not produce corn, and where this, vegetable production can be cultivated. The minister of the interior has announced this discovery . to the emperor, who was greatly pleased with it, and order- ed a present to be given to the person who transmitted the roots to Petersburgh. Mr. Andrews’s Work on Roses. —It is not unworthy of remark, that the Rose, though it has ever been celebrated as the queen of flowers, has been yery little an object a: of Lectures. 285 ef the attention of botanists. It is hoped that this un- accountable defect, which has frequently been objected to the science of botany, will be in some degree removed by the new work lately announced by Mr. H. C. Andrews of Knightsbridge, the merits of whose Botanist’s Reposi- tory, and Engravings of Heaths, are well known. It is to be a complete Monograph of the Genus Rosa, and will con- tain coloured figures of all the known species of Roses, and their numerous and beautiiul varieties, drawn, engraved, described, and coloured, from the living plants, by Mr. Andrews. LECTURES. At the Theatre of Anatomy, Blenheim-strect, Great Marlborough-street, the Autumnal Course of Lectures on Anatomy, Physiology, and Surgery, will commence on Tuesday, the first of October, at two o’clock in the after- noon, hy Mr. Brookes. . In these Lectures the structure of the human body will be demonstrated on recent subjects, and further illustrated by preparations, and the functions of the different organs will be explained. The surgical operations are performed, and every part of surgery so elucidated, as may best tend to complete the ope- rating surgeon, ? The art of injecting, and of making anatomical prepara- tions, will be taught practically. Gentlemen zealous in the pursuit of zoology will mect with uncommon opportunities of prosecuting their re- searches in comparative anatomy. Surgeons in the army and navy may be assisted in re- newing their anatomical knowledge, and every possible at- tention will be paid to their accommodation as well as in- struction. Anatomical Converzationes will be held weckly, when the different subjects treated of will be discussed familiarly, and the students’ views forwarded.—To these none but pupils can be admitted. . Spacious apartments, thoroughly ventilated, and replete with every convenience, will be open in the morning’ for the purposes of dissecting and injecting ; where Mr. Brookes attends to direct the students, and demonstrate the various parts as they appear on dissection. An extensive Museum, containing preparations illustra- tive of every part of the human body, and its diseases, ap- ertains to the Theatre, to which students will have occa- sional admittance.—Gentlemen inclined to support this school 286 Lectures. school by contributing preternatural or morbid parts, subs jects in natural history, &c. (individually of Jittle value to the possessors,) may have the pleasure of seeing them pre- served, arranved, and registered, with the names of the donors. The inconveniences usually attending anatomical inves- tigations are counteracted by an antiseptic process, the re- sult of experiments made by Mr. Brookes on human sub- jects at Paris in the year 1782; the account of which was delivered to the Royal Society, and read on the 17th of June 1784. This method has since been so far improved, that the florid colour of the muscles is preserved, and even heightened.—Pupils may be accommodated in the house.— Gentlemen established in practice, desirous of renewing their anatomical knowledge, may be accommodated with an apartment to dissect in privately. The first Monday in October next will commence 4 Course of Lectures on Physic and Cheinistry at the Labo- ratory in Whitcomb-street, at the usual marning hours, viz. on Therapeutics at a quarter before eight, on the Practice of Physic at half after eight, and on Chemistry at a quarter after nine o’clock. _These Lectures are delivered every morning, except on Saturdays, when at nine o’clock a Clinical Lecture is given on ihe cases of Dr. Pearson’s patients in St. George’s Hospital. By George Pearson, M.D. F.R.S. of the College of Phy- sicians, and Senior Physician to St. George’s Hospital, &c. &c. N. B. Proposals may be had at St. George’s Hospital, and at No. 52, Leicester-square. The following Courses of Lectures will be delivered at the Medical Theatre, St. Bartholomew’s Hospital, during the ensuing winter: - On the Theory and Practice of Medicine, by Dr. Roberts and Dr. Powell. . ) On Anatomy and Physiology, by Mr. Abernethy. On the Theory and Practice of Surgery, by Mr. Aber- nethy. ; On Comparative Anatomy and Physiology, by Mr. Ma- cartney. : On Chemistry, by Dr. Edwards. On the Materia Medica, by Dr. Powell. ; _ On Midwifery and the Diseases of Women and Chil- dren, by Dr. Thynne. Anatomical List of Patents. —Tiavels in Africa. es7 Anatomical Demonstrations and Practical Anatomy, by Mr. Lawrence. The Anatomical Lectures will begin on Tuesday, October the first, at two o’clock, and the other Lectures on the suc- ceeding days of the same week. Further particulars may be learned by applying to Mr. Nicholson, at the Apothecary’s Shop, St. Bartholomew’s Hospital. LIST OF PATENTS FOR NEW INVENTIONS. Malcolm Cowan, of Gloucester-place, Portman-square, in the county of Middlesex, commander in the royal navy ; for improvements in the construction of sails for ships and vessels of all descriptions. Robert Bazber, of Billborough, in the county of Notting- ham, gentleman ; for new and improved modes of making and shaping stockings and pieces, and also some new and improved kinds of stocking-stitch and warp-work. Thomas James Plucknett, of Butt-lane, Deptford, in the county of Kent, gentleman ; tor a method of mowing corn, grass, and other things, by means of a machine moving on wheels, which may be worked either by men or horses. William Collins, lieutenant in the royal navy; for a ventilator, upon a new or improved construction, for the pur- pose of ventilating tents and marquees of every description. TRAVELS IN AFRICA. By letters received, we learn that the celebrated traveller Mungo Parke, with bis companions Messrs. Anderson and Scott, who sailed from Portsmouth in the Crescent trans- port, about six months ago, having touched at the islands of St. Jago and Goree, arrived at Kayay, on the river Gam- bia, on the 14th of April, whence they were to proceed in a few days into the interior of Africa, to effect the business on which they were dispatched, and which we believe to be. of a very important and extensive nature. The heat was at that time so excessive, that the thermometer was constantly at 100 degrees and upwards in the shade, and for two or three hours after sunset continued at from 82 to 92 de- grees. -We are happy, however, to hear that notwith- standing this excess of heat the whole party had enjoyed perfect health: they had only lost one of the fifty men they had received from the African corps at Goree, though they had been above fourteen days in the river; and this man had been unwell before they left the island. Mr. Seetzen, another traveller, arrived on the 4th of March at Aleppo; but intended in fourteen days to set out for Damascus, whence he was to proceed through Egypt to the interior parts. of Africa. METEORO- Meteorology. METEOROLOGICAL TABLE By Mr. Carey, OF THE STRAND; For August 1805. Thermometer. hee tas Vigidee 4 Oia S eh Pa Heighr of | 5 4 2 3 gl 8 10 ms the Barom.| % 2 ¢ Weather. x 3 ue Inches. Es : 3 =) “ Oak 29°68 54° |Fair ‘68 26 |\Showery 68 35 |Showery 78 39 |Fair 68 25 \Showery 58 290 «|Showery 44 38 |Stormy “77 21 |Showery “90 33 |Cloudy 64 63 |Fair, with strong wind = A 74 |Fair 86 4g {Fair "87 51 \Fair "89 30 \Cloudy 30°02 53 |Fair ‘00 52 \Fair 29°78 52. |Fair ‘00 64 |Fair “95 57. \Showery 30°00 65 |Fair 29°90 44 |Fair "99 52 |Fair “86 35 |Cloudy, and heavy rain at night “52 0 |Showery 62 25 |Showery "95 15 |Cloudy 30°12 35 {Fair 18 39 (| Fair 15 51 |Fair 02 35 |Fair 29°95 94 |Cloudy N. B. The barometer’s height is taken at noon. —_— re [ 289 ] XLII. Extract from a Memoir entitled ‘ Considerations on Colours, and several of their singular Appearances.” Read in the Mathematical and Physical Class of the French National Institute, Ventose 13, dn 13. By C. A. Prizur*. ‘Pus author of this memoir endeavours to account for several phenomena which appear to him not to have been before properly explained: or, rather, his object is to give a general theory, by the help of which all the cases of co- Icured appearances, and even the most singular, may be referred to certain principles. He sets out from known opinions in regard to the diffe- rent kinds of luminous rays; on the mixture resulting from several of these rays taken at different places of the solar spectrum, and among others on that very remarkable case when the rays are so chosen that their union produces on the organ of sight the sensation of whiteness, even if two kinds of rays only be employed. For these ideas we are indebted to the discoveries of the immortal Newton; and they flow immediately from the method which he proposed for determining what colour will be obtained from the mixture of any given quantities of other colours. If we are desirous of comprehending fully what takes place in the vision of colours, it is first indispensably ne- ecssary that we should be familiarised with knowing the shades composed of different simple rays, and with forming correct ideas of black and white, and the complication which they produce in coloured appearances ; and in particular to make ourselyes acquainted with the correspondence of co- lours, which, taken two and two in a certain order, are sus- ceptible of forming, by their union, white or any other complex shade at pleasure. Two colours which have this kind of relation are called complementary colours ; one of them being given, the de- termination of the other may be made, with more or less precision, by experience, calculation, or mere reasoning ; and the consideration of them may be applied with much utility to a great number of cases, as will be seen hereatter. Several details are here given, which those versed in optics, or habitually acquainted with the mixture of co- lours, may readily supply: besides, the rest of the me- * From the Jeurnal de Chimie,. No. 160. Vor. 22. No. 88. Sept. 1805. Ag moir, 290 Considerations on Colours, moir, of which we have undertaken to give an account, will afford us an opportunity of mentioning what will be most necessary for understanding the subject. These preliminary observations are followed by some re- marks on contrasts. The author employs this word to characterize the effect of the simultaneous vision of two substances of different colours when brought together under certain circumstances. The contrast here, then, is a comparison, from which there results a sensation of some difference, great or small. It is very generally known, and painters know it well, that a coloured matter which occupies a pretty extensive space, and brought near to, or surrounded by, some other colour, has not the same appear- ance as when it has near it other colours. But whence does this differermce arise ? Before we answer this question, let us make an essential distinction. It either relates to homogeneous colours, that is to say, formed of one kind of rays, or to complex colours, arising from a mixture-of heterogencous rays, that is to say, composed of different sorts. . In regard to the first case, it must be confessed that we are ignorant whether the bringing together different simple colours would produce any alteration in their respective appearance. As one can rarely enjoy the sight of. such colorations, and as it is not easy to dispose of them to our wish, no experiments have yet been made on their contrasts. ‘This subject, however, deserves to be studied. Jn regard to the cases of compound colours, (which is that of almost all the natural or artificial bodies, as the au- thor shows in the sequel of his memoir,) the new colours manifested by the contrast are always conformable to the - shade which would be obtained by suppressing from the colour proper to one of the bodies, the rays analogous to the colour of the other body. Thus, if we place on red paper a small slip of paper painted of an orange colour, it will appear almost yellow. Removed then to yellow pancr, the same orange slip will become almost red. After this, if it be put upon violet pa- per, it will resume a yellowish shade, but different from the preceding; and, in the last place, applied to green paper it will assume a new deeree of a red colour. The explanation of these examples according to the pro- posed rule is easy, 1f we suppose that the orange colour of the small slip observed arises (as 1s commonly the case) from an union of all the kinds of rays except the blues. A multitude of combiiations of colours placed thus aboye and several of their singular Appearances. 291 above each other produce the colour of contrast indicated by the rule here given; but there are several circumstances. which render the effect of it more striking, or modify the result. It sometimes depends on the degree of the brightness with which the observed bodies are affected: they may be uniformly illuminated, or one of them more than the rest. The quantity of Jight which has entered simultaneously into the eye by the whole field of vision has also an influence. If the bodies consist of several rows, like a series of decreas- ing circles placed one within the other, the colours of each will re-act respectively on each other. At each junction there will be on both sides a border coloured by the con- trast of the neighbouring body : these borders will extend more or less according to the splendour of the objects. The effect of one may become dull, or extinguish all the rest. The colours of contrast show themselves also with more vivacity after some moments of observation, or if the ob- jects have been agitated a little, as if to make them move slowly over the retina. It would appear that a certain fa- tigue of the eye, either instantaneous in regard to the inten- sity of the light, or more slowly by prolonged vision, con-~ curs to produce the appearances in question. But exces- sive fatigue of that organ would occasion a degeneration of the colours belonging to another mode. We ought not, then, to refer to contrasts those impres- sions mentioned by Epinus, which are propagated in the eye with acertain duration and a particular period of shades, when one has looked with intensity at a very brillant light, such as that of the sun. But the colours called by Buffon accidental, and respect- ing which Scherfer has given an interesting memoir, belong to the class of contrasts, or at least constantly follow the same law. Coloured shadows are also a phenomenon of the same kind. Count Rumford has placed this truth beyond all doubt in two memoirs, in which he has treated this subject in an interesting manner*. The author of that which we here analyse is of opinion, that we must ascribe also to contrasts those appearances of the solar light received through a hole ina coloured cur- tain, which general Meusnier remarked in consequence of their singularity. He assimilates to this also several cases of colours exhibited by opals, or more generally by bodies * Philosophical Essays, vol. i, p. $19 et seq. 1802, London edit. » 2 containing 292 Considerations on Colours, containing sensibly opake parts disseminated throughout 2 pellucid substance. By the: same reasons he explains the colours under which the grayish dust collected by age on old paper or coloured stuffs shows itself, and deduces the same consequences in regard to the blueish appearance of the veins of the human body. He proposes, likewise, a new method of rendering very sensible the colours of contrasts more lively even than by the known process of accidental colours, and yet without eccasioning extraordinary fatigue to the eye. The latter condition 1s of importance, for it is known that it is dan- gerous to expose to forced exercise an organ so delicate as the eye. This method consists simply (w nies one is in an apart- ment and in the open light) in placing before the window the painted pieces of paper on which you intend to observe the coutrasts, as in the example before mentioned. As the eoloured paper , then, which serves asa field has a semi- transparency, and by these means is more illuminated, while the small band of another colour placed over it is, on aecount of the double thickness, more opake and in the shade ; the colour arising from the contrast becomes thus more striking. It is this di isposition which produces the singularly strik- ing effect of the contrast of a small piece of white card ap- plied successively to paper, glass, or stuff of any colour whatever. When the transparent body is red, the opake white appears of a blueish green ; it is then seen decidedly ae if the ground be orange; then of a sort of violet on a ellow ground, or green on crimson, &c.; always accord- ip to the exact correspondence of the complementary cc- lours. It is here to be observed, that according to the rule in- dicated, if from the white which is formed by the union of all the coloured rays we suppress, for example, the red rays, the remaining bundle ought to be seen under the co- Jour of a very pale blueish green ; but as the sinall white piece in the preceding experiment 1s in the shade, the black which results from 1t may be of the degree proper for de- stroying the eflect of the white, and then the Ulueish green appears of a bright shade. The same reasoning is appli- cable to the cases of all the other colours. To produce well the effects here announced, in repeating these expe; uments, it is necessary, when the op portunity of elear weather has been obtained, to guard acsiust Hic reflec- tions of neighbouring bodies, and against deuble confrasts. ‘ a Thus, and several of their singular Appearances. 293 Thus, when the bright light conveyed through a window surrounds'the transparent paper, it may increase very sensibly the splendour of the colour of contrast, or injure it by pro= ducing another shade according to the colours of the bodies subjected to observation. In a word, one may always re- move this inconvenience by concealing the troublesome objects by a piece of black pasteboard or stuff, or by look= ing through a blackened tube which confines the field of sight to the extent necessary. ) This knowledge of contrasts may be applied-with great advantaye to those arts which have a relation to colours. The painter knows that one cannot be placed indifferently in the neighbourhoed of another. But when one knows the law to which their re-action is subject, one knows bet- ter what must be avoided or done to increase the splendour of the colour which it is necessary to heighten : asuccessive comparison of them furnishes also yaluable indications in regard to their nature or their composition. . This is what the author himself put in practice with advantage in his manufactory of colours and paper-hangings. These cousiderations,in regard to contrasts led him to the examination of a very singular case proposed and treated of by Monge witb his usual sagacity* ; namely, the white appearance under which a coloured body is sometimes seen when viewed through a piece of vlass of the same colour; some uncertainty remained in regard to the cireumstances really necessary for producing this effect. The author de- termines them by the help of his particular,experiments, and enumerates those which have a favourable influence, or the contrary.. He concludes that, when one experiences the sensation of whiteness in. these cases, it arises merely from the action cf contrasts, by which the impression of the colour is lessened or annulled, while that of a certain bright- ness still exists, and. is. remarked by the opposition of a greater degree of obscurity. This manner of considering the subject leads to a new definition of whiteness, in which there is certainly nothing repugnant: white to us is the sens sation of light when no particular colour predominates or is percewed. In the subsequent part of his memoir the author employs himself in particular with the coloration, of different opake or transparent bodies ; that is to say, he endeavours to dis- cover what are those luminous rays which any coloured body is really susceptible of reflecting ar transmitting, * Annales de Chimie, tom, iii. i my Tis 294 Considerations on Colours, His means of making experiments are simple. If the body be opake, it is placed on a piece of black stuff in order to be observed with the prism. He endeavours to give it a rectangular form ; or, if it is not susceptible of being cut, it is covered with a piece of black pasteboard pierced with a hole of that form. The coloured fringes, then, manifested on the two opposite edges indicate the kind of rays which are reflected, and consequently those which are absorbed when the nature of the illuminating bundle is known; on which it is still to be remarked that, as the fringes them- selves are of complex shades, we must separate the simple kinds. When a person has had some practice, a bare in- spection will be sufficient. He may be formed to this habit, and the want of it may be supplied by guiding himself by cards representing each kind of rays placed over each other in order, removing them gradually agreeably to the different © refrangibility ; or he may employ a plate or board, con- structed according to Newton’s method, for determining - the shades composed of different elementary colours. If the body subjected to examination be diaphanous, it will be proper to view it through the aperture of the card before spoken of, in order to exclude extraneous light, in such a manner that the prism may show the fringes. Also, by placing yourself in the dark, a flame such as that of a wax taper will show through the transparent body, and, by the help of the prism, a series of coloured images corre- sponding to the rays transmitted. By proceeding in this manner, the author found that many opake bodies which he had at hand of different kinds and of all colours, either yellow, orange, or red; or green, blue, or violet, were indebted for their coloured appearance to the following conditions : Ist, Each of the bodies always absorbs rays of the com- plementary kind of the prevailing colour. ad, The absorption, in regard to some of them, compre- hends, besides the complementary kind, other rays colla- teral to that species, and more or less numerous. 3d, The darker the same colour is, the fewer kinds of reflected rays it presents. It must here be understood that we do not allude to mixed colours, but only to those which form a homoge- neous compound or a real combination, according to the meaning attached by chemists to that word. It is also to be remarked, that we must not confound the colour reflected from the interior of the molecule susceptible of bright or dark shades with the light sent back from the anterior sur- 2 face and several of their singutar Appearances. 295 face of the body. Though the latter overcharges more or Jess the proper colour, it is, however, easy to lessen the effects of it, and to distinguish them in experiments. Another remark proper to be made is, that the expression predominating colour ought not to signify that the rays of that colour are more abundant than the rest: this would be an error. Several kinds of rays may co-exist in the bundle which produces the colour, without any kind being, on that account, more abundant. Strictly speaking, all the elements of the bundle are dissimilar, and consequently none of them is in greater quantity. But the general tone of the colour remains analogous to that of the rays distin- guished by the name of predominating. Hence it is proper to retain this expression, provided an exaggerated significa- tion be not given to it. The author observed also transparent bodies, such as glass of different colours, and liquors contained in a flask having two broad paralle] faces. By these he found a law of absorption similar to ihat of opake bedies, but still more stiking, and without any ambiguity. This law is constantly regular. {t depends on the pecu- liar nature of the body which receives the light, and on its density and thickness. It is also determined by the hght of the illuminating body, either in regard to its force, or to the two kinds of rays which compose it. The absorption always begins with the rays most opposite to the predominating colour of the itluminated body. It continues by those which are next in the order imdicated by the spectrum. It thus extends gradually, and never by jumps, to the last kind: consequently the body becomes more and more obscure, and always terminates by being black. Sometimes it extends from one side only of the first rays absorbed ; sometimes un both sides at the same time; and it there proceeds either by an equal progress from the right and left, or by advancing more rapidly on one of the sides. If each element be separately varied, there will be in the effects a peculiar progression. That depending on the densi- ties is not always similar to that arising from the changes of thickness. By reeeiving also on the same body different kinds of light, the progress of the absorption is differently modified, and consequently the colours changed. The author quotes examples of all these eases. He de- tives them from the numerous experiments which he made with coloured glass, with acid or alkaline metallic solu- tions, with the Nquid tinctures of infusions or vegetable cecoctions. 296 Considerations on Colours, decoctions.. They exhibited curious peculiaritics ; but we shall not detail them, both for the sake of brevity, aud be- cause they may be easily tried. In short, very important consequences in regard to the reciprocal action of bodies and light arise from the whole of these observations, and perhaps they will throw some light on the grand question of the cause to which their per- manent colours ought to be ascribed. After these researches the author concludes with an exa- mination of different phenomena of various kinds. He indicates the modifications experienced in their coloration by burning coals at different degrees of incandescence. His remarks are applicable also to other bodies, such as iron in a state of ignition, or a long series of reverberated lamps seen during foggy weather, or a white light seen through a piece of glass blackened by progressive strata of smoke. In all these cases, the colours necessarily pass through a series of shades, which proceed from white to yellow, to orange and to red, more and more dark ; the reason of which he explains. Metallic oxides have also a gradation of shades according to the proportion of oxygen. A certain continued altera- tion in vegetation produces one in some of the parts of plants. The arts or chemical processes present one also under a multitude of circumstances. The manufacturer may, with advantage, derive from them indications either in regard to the progress of combinations, or to enable him to judge of the moment proper for per- forming certain operations of his labours. The author then dwells more particularly on the appear- ance of the coloured clouds, and especially those seen near the time of the rising and setting of the sun. This phe- nomenon, so generally known, bad hitherto never been ex- plained, though the ablest philosophers had made it an ob- ject of their research, It does not arise from the refraction of the ravs of the sun, but the successive absorption of these rays when they strike the lower parts of the atmosphere and those most eharged with vapours. This absorption follows laws analogous to those already mentioned. As the quantity of the vapours, and even their nature, are not similar for tsvo days in-succession, this irre- gularity produces corresponding differences in their effects. In general, the first rays attacked. by these vapours. are blue approaching to violet. Soon after they absorb the contiguous rays, gaining with more rapidity the blues pro- ys perly and several of their singular Appearances. 297 perly so called, then the greens and yellows, and continuing thus to the sels hence the yellowish, orange, and red co- lours, under which the clouds appear. “This period of shades, namely, the evening, manifests itself gradually in proportion as the sun approaches the horizon. Terrestrial objects, the part of the air near the sur, and even that Ju- muinary itself, are tinged with the same shades. When his rays can be received ona prism, it is seen that the rays really absorbed correspond to the general coloration of the moment. In consequence of the successive increase and density of the vapours traversed by the livht, clouds differently placed must at the same instant be tinged of different colours. The highest may be white, while the rest, at a less clevation, will be yellow, and aries still lower will be proportionally redder. At an equal eleva ation, the most distant from the point where the sun sets will incline to red, and the nearest to yellow. One may then sce on bodies naturally white, blue or green shadows, as Buffou and other philosophers have re- marked, They are only, as bas been already said, the effect of the contrast of ithe actual colour of the sds heak and the obscure part. Contrasts may also render complex the colour of the clouds; for example, when a ereat portion of the heavens shows a blue colour. There are some the colour of which arises merely from this cause, and some are observed some- times during the day by fliase who are on a high mountain, or in any Bihce situation which secures the eye >from the too strong direct or reverberated action of the solar light; but in this case the clouds have only a yellowssh shade, exactly of the complementary colour of the sky-blue. It is under a similar colour that the moon is sometimes seen, when she is very high, a little before or after the sua bas passed the horizon. It seems, also, that she appears thus, or even altogether white, when there exist at the same time in the atmosphere clouds variously coloured by the vapours of the east or the west. By this concourse of cir- cumstances we have a new proof of the difference of tie causes to which these colorations are owing. We must remark, in the last place, that by the irregu- larity of terrestrial localities, and the state of ‘the atmo- sphere, these phenomena may be concealed, or subject te different interruptions. In our climates, the coloration of the clouds tor the most. part docs not attain to its utmost term. Qn certain evenings, however, 1f the sky is very se- . rene 298 Considerations on Colours, &e. rene towards the part corresponding to the sun, and if there be over our heads any of those light clouds which are ex- ceedingly high, they will be seen at a later period clothed with a brilliant red, beightened by the diminution of the light on the earth, soon after darkened, and at length ex~ tinguished in the shade. CONCLUSION. Notwithstanding the many fine discoveries already made in regard to light, the theory of the production of colours has not yet acquired that generality which renders it appli- cable to all cases, and to that simplicity of principles to which we are always conducted when we discover the real laws of nature. Many phenomena have never been ex- plained; and the explanation given to several necessarily requires to be rectified. The author proposes to establish changes in theory, the want of which he points out. He founds his reasoning partly on the doctrine and facts gene- rally admitted, and partly on other formation less diffused, though Jong known, and on his own observations. But he is far from flattering himself with the idea of having pre- sented these objects properly in a sketch such’ as this me- moir. He even was soon sensible that a subject so exten- sive and complex would require more time and labour. To fill up many vacuities, to develop several.points, and to rectify and extend others by researches, new experi- ments, and profound reflection,—such is the ample task of improvement. If his health and occupations permit, he will endeavour to undertake it. It would be of utility, and alsa just, to give at the same time a short account of what we are indebted to the great Newton, who opened this career in so admirable a manner, and to the philosophers who have discovered new points, and removed difficulties. Greater precision ought also to be employed in the langnage relating to colours, proportioned to the increase-of our knowledge, and the present state of science and the arts. In aword, it would not be too much, in such a branch of science, to add the resources of caleula- tion and geometry to ail the riches of experience, and, if possible, to the advantages of the best method. [ 299 ] XLIV. On the Variations of the Terrestrial Magnetism in different Latitudes. By Messrs. Hompoipr and Brot. Read ly M. Brovr in the Mathematical and Physicab Class of the French National Institute 26th Frimaire, An 13. (17th December 1804.) [Concluded from p. 257-] "Tue calculation is as follows :—I suppose that the point B (fig. 3.) is the north magnetic pole of the earth, and that the point A is the south magnetic pole: I suppose also that there is in the point M, at the surface of the earth, a mo- Jecula of the austral fluid which is attracted by B and re- pelled by A in the inverse ratio of the square of the di- stance; and I require what will be the direction of the power resulting from these two forces acting on that mole- cula. It is evident that this direction will be that also which would be assumed in the point M by the needle of a compass freely suspended: for, in consequence of the smallness of the needle in comparison of the radius of the earth, the lines drawn from its points to one centre, Bor A, may be considered as parallel, especially if the points A and B are near the centre of the earth; which is the case with nature, as may be seen. I shall first suppose that the earth has a spherical figure, and that the two poles A and B are equal in force; I shall then examine how far the latter supposition agrees with the results observed. Let AM then = D’, BM=D, CP =2; PM=y, the angle MCP =u, CA = CB =a, and I shall make a = kr; 7 being equal to the radius of-the earth, and Ka constant but indeterminate quantity. Let X,Y, also be the forces which attract M in a direc- tion parallel to the axes of the co-ordinates, and § the angle which the resulting force makes with the axis ABC. We shall first have the following equations, in which F is the magnetic force, at a distance equal to unity. ¥ X= D? cos, MBD — D2 cos. MAD; DD? = yy? + (x+e)? =r? + Qaxis + a* aug | yr edt ies ae pr Sm MBD — Dz sin. MAD; De = yx? +(x — a)? = 72 axis + a’, oT 300 Variations of the Terrestrial Magnetism or by putting for the cosines their values ; x See) F (x + a) D3 . Ds x AEG Fy — D: D3 7) and as we have tang. 6 = on we shall have alsu eats Gey wrth, D: D3 y (D's — Ds) tang. B = ra, g+a — ¢(D%—D3) —a (D2 4 D5); D:.” Ds | ae putting for x, y, and a, their values, r cos. 7; 7 sin. x; ee 3 y sin. 2 tang. 6 = ————__-—____—_ —_ ; D'3 + D3, ? cos. u — K Viegas sae, D’?? = 1r2 (1 + 2K cos.u + Ke); Dv =r: (1 — 2K cos. u + K2); which gives the system of the two equations, sin, tang. B = NK a. € ees kEOS LN a: cos.u — K ee who K (4 ia) (+2 Koos. u4+K2)?4 (1—2Kcos.u+K?2) i Rei (142K cos.u+K2)?—(1—2K cos.v+K)? These equations determine the direction of the magnetic needle in regard to each point M, the distance of which from the magnetic equator is known; but it is seen that this direction depends on the quantity K, which represents the distance of the magnetic centres from the centre of the earth: this distance being expressed in parts of the terres- trial radius, we must therefore first determine this quantity from observations. To do it in the manner of approximation, and thus ac-’ quire a first idea of the value of K, I have chosen an obser- vation made by M. Humboldt at Carichana in 7*2978° (6° 34’ 5”) of north latitude counted from the terrestrial equa- tor, and 78°111° (70° 18”) west longitude reckoned from ihe in different Latitudes. 301 the meridian of Paris; which gives 16: 596° (14° 59% 95”) of latitude counted from the magnetic equator, and 53-7390? {48° 21" 53’) of west longitude proceeding from the node formed by that oes with the equator of the earth. The inclination of the magnetic needle was. observed in that place by M. Humboldt in the month’ of .Messidor, year 8, and found to be equal to 33°78° of the centigrade division *. A comparison of this result, with the other observations of M. Humboldt, shows that it ey be indeed considered as agreeing to that latitude. To make use of it [ have success sively given to K different values in the formula: I/have calculated the inclinations resulting from that latitude; and, comparing these results with that which M. Humboldt really observed, the progress of the errors naturally led me to the most proper supposi- tion. The following is a table of these trials : Values of K. Inclinations of the Needle. Errors. K=1 7°73° 26°04° K = 06 18°80 14°97 K = 0°5 22°04 11°73 K = 0-2 29°38 4°39 K = 01 30°64 | 3°13 K = 0°01 31°04 ve 2°73 K = 0°001 31°07 27 The first value of K would place thi centre of the mags netic forces at the surface of the earth and the poles of the magnetic equator. It is seen that this supposition cannot be admitted, because it would give an increase of inclina- tion much less rapid than that indicated by observations. The case is the same with the following results, which place the centres of action on the terrestrial radius at different distances from the centre of the earth: but-it is seen also, in general, that they approach more and more to the truth in proportion as this distance becomes less; which evidently shows that the two centres of action of the mag- netic forces are situated near the centre of the earth. All the other observations of M. [lumboldt would also lead to the same consequence. The most proper supposition would be to make K null, or so small that it would be needless to pay attention to it; which amounts to the same thing as to consider the two centres of action placed, as we may say, in the same mo- Jecula. The result, indeed, obtained in this manner is the most exact of all; it is equal to 3i°0843°: this value is still * All the measures of inclination which I have given in this memoir will be expressed, like those of M. Humbeldt, in decimal parts of a quadrant. a little 302 Variations of the Terrestrial Magnetism a little less than that which M. Humiboldt observed, and the difference is equal to 2°69; but it must be considered also that the formula from which we derive these values supposes the position of the magnetic equator to be per- fectly determined; but it may not be so with the utmost exactness, according to the only two observations of Lapey- rouse and Humboldt, which we have employed. It is there- fore by studying the progress of the formula, and comparing it with the observations, that we are able to appreciate it justly; after which we may think of remedying the small errors with which it may be accompanied. To obtain the result [| have here mentioned, and which is, as it were, the limit of all those which may be obtamed by giving to K different values, it is to be remarked that the quantity 27 Dade D* K (55 pi) OF K (1+ 2Kcos.u + K:)2 + (142K cos. y 4K (1+ 2K cos.u + K:)2 — (1—2K cos.u + K2)3 becomes when K is null, but by applying to it the methods of known quantities it will be found that its value in this supposition is really determinate and equal to ny Sion By substituting this in the formula we shall have ; sin. w tang. 6 = Oia o CRE TT 53 COS, u aun equation which may be reduced to this form: cos. “i — sin. 2% cos.2u + 4 4 which will easily give the value of 8: and when this value is known we shall have the inclination I, by the following formula: tang. B = I= i100 + u — 4, which will serve throughout the whole extent of the two hemispheres, From the progress T have traced out it is seen that the preceding formula is not merely an empyric construction of observations ; on the contrary, it is totally independent, and ony supposes the inclination of the magnetic needle to be produced in different Latiiudes. of 303 “produced by a magnet, infinitely small, placed in the centre of the terrestrial surface; but by calculating from this for- mula the inclination for the different latitudes, [ have found precisely the same numbers as M. Humboldt observed either in Europe or in America: and it is not his observations onl that are represented in this manner; but those which have been: made in Russia, and at Kola in Lapland, during the last transit of Venus, are also comprehended under the same jaw. This is proved by the table annexed to this memoir, in which I have calculated the observations of Mallet and Pictet, with a part of those of M. Humboldt, which I took at random, but, however, in such a manner as to include all the rest in the intervals. It is seen that the results of the formula deviate very little froin the observations; but these differences may be rendered still smajler. By examining, indeed, the progress of the errors, it is seen that the numbers given by calculation are a hittle too small in America for the low latitudes, and a little too great for the high latitudes ; which shows that the whole may be allowed, with some slight modifications, either by changing, however little, the node and inclination of the magnetic equator, which two observations cannot determine with the utmost exactness, or by displacing ever so little our small magnet, leaving, however, its centre in the plane of the magnetic equator, and placing it in such a manner that it shall be a little nearer America than Europe. It is by the observations themselves, when we shall have a greater number, that we must be guided in these small correc- tions. In a word, it must not be expected that we can represent in a rigorous manner, by a mathematical law, all the in- clinatiens observed ; for the phenomenon of tie inclination, though more regular than the other magnetic effects, is not free from some anomalies: this may be easily seen on con- Structing the curve given by the observations themselves. Thus, for example, the inclination observed at Popayan is 0° 10’ greater than at St. Carlos del Rio Negro, though the magnetic latitude of the Jatter is 0-6852° (3° 7’) greater. The case is the same with observations made at Javita and Santa-Fé. Other anomalies are discovered in the compara- tive progress of the observations and formula. This is the case in regard to Carichana, St. Thomas de la Guyane, and Carthagena. ‘The increase of the inclination from the first to the second of these points is'by no meang in harmony with the increase from the second to the third; and if we compare 304 Fariations of ‘the Terrestrial Magnetism compare together the intensities observed in these dif- ferent places, the anomalies they exhibit announce im some measure those which the inclination ought to ex- perience. The cause of these anomalies becomes evident from what has been already remarked; they are merely the effect of local circumstances, and arise trom the small systems of attraction by which the general phenomena are ‘modified. This must be sensible im particular for that part of America which M. Gumboldt travelled over, and which is traversed throughout 1 its whole length by the grand chain of the cor- dillera of the Andes. It is also in these places that the most considerable differences exist. Popayan, for example, is situated near the volcanoes of Sotara and Ponta ce 3 It is joined t to basaltic’ mountains abounding with magnetic iron. Near Sulumito, to the east of Popayan, these basaltic co- lumns have very striking poles: in hke manner Mexico is situated at the height of 1160 toises on the ridge of the grand cordillera of “Lenschtitlan; the cround there is co- ered with porate basaltes and amygdaloids s, which are almost all charged with magnet tic iron. Must not all these eauses have a Sensible influence on the inclination of the magnetic necdJe ; and must not the different dispositions of the. ferruginous masses, or their change of state, in conse- quence of the action of nature, produce also variations ? M. Humboldt made on this point a decisive observation : the earthquake of the 4th of November 1799 changed at Cumana the inclination of the needle. On the Ist of No- vember it was 43° 65’; on the 7th it was only 42°75’; and ten months after it returned to 42° 85’: but it did hie re- gain its former value; the intensity of the magnetic force was not changed by ihe effect of this earthquake. li is proved, then, by these observations, that local cir- cumstances may have on the inclination a sensible influ- ence; and this influence is remarked in the countries tra- versed by M. Humbeldt*. It appears, therefore, that the mathematical hypothesis which we have employ red. re: ily expresses the law of nature at Ieast tothe north of the m aonetic equator; for, though the first results observed towards the south scem to Bend to italso, the uncertainty under which we are in regard to the true cause of these phenomena must stop our conjectures, and * We can observe that the anomalies arc sensible in particular in the islaznds.—Nole by the duthors of the Memoir. prevent in different Latitudes. 305 prevent us from extending too far the consequences of the Jaws which we observe*. -From the preceding results, we may calculate the points where the axis of the magnetic equator pierces the terres- trial surface; for their latitudes are equal to the comple- ments of the obliquity of that equator, and their meridian is at 100° of longitude from its nodes. The north magnetic pole is found also at 97°7975° (79° 1’ 4”) of north latitude, and at 33°3719° (30° 2’ 5”) of longitude west from Paris, which places it to the north of America. The other mag- netic pole, symmetric to the preceding, 1s situated in the same latitude south, and: at 66°6281° (149° 67’ 55”) of lon- gitude east from Paris, which places it amidst the eternal Se: indications entirely.analogous to those of Wilke and Lemonnier. 1f we could reach these poles, the compass would be seen vertical ; but if any confidence can be placed in the law which we have discovered, this would be the only difference which would be observed in regard to the inclination, and we should be still as far distant as in Europe from the real centres which produce it. This result might appear to be of such a nature as to diminish the interest one might have in visiting these horrid regions, had we not also the hope of discovering there new phenomena in regard to the inten- sity of the magnetic force, and the influence of meteors. These consequences do not entirely accord with the opinion pretty generally received, and which ascribes the increase of the magnetic effects towards the north to the great quantity of iron dispersed throughout these regions 5 but it appears to us that this opinion is not agreeable to the truth. The cordillera of the Andes contains an enormous quantity of magnetic iron: the native iron of Chaco, that roblematic mass analogous to that of Pallas, and those of a ccackns in Mexico, is found even under the tropics T. * Since this memoir was read, we can advance something ‘more positive, Observations made at the Cape of Good Hope, Cape Horn, and New Hol- land, by different navigators, are very exactly represented by our formula $ and it follows, that it extends also to the austral hemisphere. We hope soon to have numerous and very exact observations on the inclination of the needle in that part of the earth. But we have thought it our duty to add to our table such results as relate to it, and which we have been able to procure. We have inserted also two observations on the intensity, made with great care by M. Rossel, during the expedition of d’Entrecasteaux, which are very important, as they prove that the terrestrial ‘magnetic force in- creases also in the austral hemisphere in proportion as one removes from the equator.—Note ly the Authors of the Memotr. “ + We may now add to the preceding considerations this decisive fact, that the intensity also increases when one approaches the south pole—Note Ly the Authors of the Memoir. Vol. 22. No. 88. Sept.1805. U On 306 Variations of the Terrestrial Magnetism On seeing the inclinations of the compass so exactly re- presented 1 id our hypothesis, we endeavoured to discover whether it could be applied also to the intensities observed by M. Humboldt ; but we found that it did not apply. © It gives, indeed, an increase of the magnetic forces from the equator to the pole; but this increase, which at first is too slow, becomes aftenwards too rapid: I have not yet been able to try whether the small displacement of the ter- restrial magnet will contribute towards representing them better: but it must be remarked, that the series of the in- tensities is extremely arHitnsieals and contains an infinite number of anomalies ; so that local phenomena may have on this phenomenon a much more sensible influence than on the inclination. On reviewing the results which we have given in this memoir, it is seen that we have first determined the posi- tion of the magnetic equator by direct observations, which had never been done before ; we have then proved that the magnetic force increases in procee ‘ding from that equator to the “poles : in the last place, we have given a mathematical hy pothesis, which when reduced toa formula satisfies all the inclinations hithérto observed. Supposing, as we have done in this formula, the smal} corrections of which it is susceptible, its utility becomes evident, either for making known, in the course of time, the variations which may take place in the action of the terres- trial magnetism, or to ascertain or even foresee the value of the inclination, which in a great many cases 1s of great im- portance. For example, near the magnetic equator, the increase or diminution of the inclination will’ indicate toa vessel on a voyage whether she has gained or lost in latitude by cur= rents. This knowledge of the latitude is sometimes as im- pee as that of longitude. On the coasts of Peru, for examp! e, the currents tend from Chiloé to the north and north-east with such force, that one may go from Lima to Guayaquil in three or four days, and two, three, and some- times five months are necessary to return. It is conse- quently. of the greatest importance for vessels coming from ‘Chili which stretch along the coast of Peru, to know their latitude. If they go beyond the port to which they are bound they must work to the southward, and every day’s progress requires often a month of return. Unfortunately, the fogs which prevail during four or five months on the. coasts of Peru prevent navigators from distinguishing the, form of the coast; nothing is seen but the summits of the Andes, in different Latitudes. 307 Andes, and that of the peaks which rise above that stratum of vapours; but the figure of it is so uniform that pilots fail into mistakes. They often remain twelve or fifteen days without seeing the sun or the stars, and during that interval they come to anchor, being afraid of overshooting their port: but if we suppose that the inclination of the magnetic needle in the ports to the south of Lima is known, tor example at Chancay, Huaura, and Santa, the dipping needle will show whether it be, in regard to Lima, to the south or the north. It will shew at the same time opposite what point of the coast a vessel is; and this indication will be attended with more exactness than one could hope for, be- cause in these seas the inclination varies with extraordinary rapidity. © M. Humboldt, to whom we are indebted for these remarks, observed in these seas the following values ; Places South Latitudes, Inclinations. Huancey , - 10° 4’ - ¥' 6,80? Huaaura - 1’ 3 ~ 9,00 Chancay - PLUS a) Gi 1 POISE These observations prove that the error of three or four deerecs in the inclination in these seas would produce but a degree of error in latitude; and, on account of the tranquil- lity of the Pacifie Ocean, the inclination may be observed to within a degree nearly. Frequent instances of such re- sults may be seen in books of voyages. In hke manner, if one knew exactly the inclination at the mouth of the Rio de ja Plata, it would be very useful to navigators, who, when the Pamperos blow, remain fifteen or eighteen days without seeing the heavenly bodies, and go on different tacks for fear of losing the paralldl of the mouth of that river. In a word, the inclination may indicate also the longi- | tude in these seas: and this'method may be employed when others fail. A vessel which sails there in the direction of a parallel could not find its longitude either by a chrono- meter or the declination of Halley, unless a star could be seen in order to take aa horary angle or the magnetic azi- muth. The dipping aged then, throws light on the lon- gitude amidst the thickest fogs. We point out this method as one of those which have only a local application; but- hitherto little attention has been paid to it. These ideas may be extended and rectified by able navigators. In general, if the inclination of the needle, and the law we have tried to establish, could be depended on, to observe the inclination and the terrestrial latitude would be sufh- cient to determine also the longitude: but we have not yet | examined the extent of the errors of which this methdd U2 6. 308 On the Variations of the Terrestrial Magnetism. be susceptible, and consequently we confine ourselves to a mere indication of it. The phenomenon of the inclination has in maritime ob- servations a particular and very remarkable advantage, namely, that of not being subject to those great progressive variations which affect the declination. Without repeating what we have already said above on the supposed constancy of this phenomenon, it may be remarked chat our formula even affords a new proof that it may comprehend in the same Jaw the observations made thirty-six years ago in Lapland, those which Lacaille brought back in 1751 from the Cape of Good Hope, and those which M. Humboldt has Jaiely made in America. In short, when we tried to represent the inclinations in different latitudes by the supposition of a magnet infinitely small, very near the centre of the earth and perpendicular to the magnetic equator, we did not pretend to consider that hypothesis as any thing real, but only as a mathema tical abstraction useful to connect the results, and proper to ascertain in future whether any changes exist. In regard to the declination and intensity, we freely confess that we are entirely unacquainted with their laws or their causes 5 and if any philosopher is so fortunate as to bring them to one principle, which explains at the same time the varia- tions of the inclination, it will no doubt be one of the greatest discoveries ever made. But this research, exceed- ingly difficuit, requires perhaps before it be attempted more observations, and in particular more precise observations than have hitherto been collected. For this reason we thought we might present to the class the preceding re- searches, imperfect as they are, begging it to receive them with indulgence. Should we be so happy as to find that our results appear of any utility, we propose to unite all the exact observations which have been made on this subject, in order to give the utmost degree of precision to the law we have discovered. 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P.R.S.* MY DEAR SIR, Tris well known that the fluid, generally called the sap, in trees, ascends in the spring and summer from their roots, and that in the autumn and winter it is not, in any consi- derable quantity, found in them ; and [ have observed in a former paper, that this fluid rises wholly through the al- burnum, or sap-wood. But Du Hamel and subsequent naturalists have proved, that trees contain another kind of sap, which they have called the true or peculiar juice, or sap, of the plant. Whence this fiuid originates does not appear to have been agreed by naturalists; but I have of- fered some facts to prove that it is generated by the leaft; and that it differs from the common aqueous sap, owing to changes it has undergone in its circulation through that or- gan: and I have contended that from this fluid (which Du Hamel has called the suc propre, and which I will call the true sap,) the whole substance, which is annually added to the tree, is derived. I shall endeavour in the present paper to prove that this fluid, in an inspissated state, or some con- crete matter deposited by it, exists during the winter in the alburnum, and that from this fluid, or substance, dissolved in the ascending aqueous sap, is derived the matter which enters into the composition of the new leaves in the spring, and thus furnishes those organs, which were not wauted during the winter, but which are essential to the further progress of vegetation. Few persons at all conversant with timber are ignorant, that the alburnum, or sap-wood, of trees which are felled in the autumn or winter, is much superior in quality to that of other trees of the same species which are suffered to stand till the spring, or summer: it is at once more firm and tenacious in its texture, and more durable. This su- periority in winter-felled wood has been generally attributed to the absence of the sap at that season; but the appearance ' and qualities of the wood seem more justly to warrant the conclusion, that some substance has been added to, instead of taken from it, and many circumstances induced me to % From Philosophical Transactions of 1805, part i. + See Philosophical Transactions of 1801, page S36. J4 suspect 310 State mm which the true Sap of Trees suspect that this substance is generated, and deposited withiss it, in the preceding summer and aatumn. Du Hamel has remarked, and is evidently puzzled with the circumstance, that trees perspire more in the month of August, when the leaves are full grown, and when the an- nual shoots have ceased to elonvate, tham at any earlier period ; and we cannot suppose the powers of vegetation to be thus actively “employed, but in the execution of some very important operation. Bulbous and tuberous roots are almost wholly generated after the leaves and stems of the plants, to which they belong, have attained their full growth 5 and J have constantly fonnd, in my practice as a farmer, that the produce of my meadows has been immensely in- creased when the herbage of the preceding year had re- mained to perform its proper office till the end of the au- tumn, on ground which had been mowed early in the sum- mer. Whence I have been led to imagine, that the leaves, both of trees and herbaceous plants, are alike employed, during the latter part of the summer, in the preparation of matter calculated to afford food to the expanding buds and blossoms of the succeeding spring, and to enter into the composition of new organs of assimilation. If the preceding hypothesis be wel} founded, we may ex- pect to find that some change will gradually take place in the qualities of the aqueous sap of trees during its ascent im the spring; and that any given portion of winter-felled wood will at the same time possess a greater degree of spe- cific gravity, and yield a larger quantity of extractive mat- ter, than the same quantity of wood which has been felled in the spring orin the early part of the summer. To ascer- tain these points J made the experiments, an account of which J have now the honour to lay before you. As early in the last spring as the sap had risen in the sycamore and birch, I made incisions mto the trunks of those trees, some close to the ground, and others at the elevation of seven feet, and I readily obtained from each in- cision as much sap as J] wanted. Ascertaining the specific gravity of the sap of each tree, obtained at the different elevations, I found that of the sap of the sycamore with very little variation, in different trees, to be 1.004 when extracted close to the ground, and 1.008 at the height of seven feet. The sap of the birch was somewhat hghter ; but the increase of its specific gravity, at greater elevation, was comparatively the same. When extracted near the- round the sap of both kinds was almost free from taste ; But when. obtained at a greater height, 1t was sensibly gon r Lee / is deposited during Winter. 312 The shortness of the trunks of the sycamore trees, which were the subjects ef my experiments, did not permit me to extract the sap at a greater elevation than seven feet, except in one instance ; and in that, at twelve feet from the ground, I obtained a very sweet Suid, whose specific gravity was 1.012. : I conceived it probable, that if the sap in the preceding cases derived any considerable portion of its increased spe- cific gravity from matter previously existing in the alburnum, I should tind some diminution of its weight, when it had continued to flow some days from the same incision, because the alburnum in the vicinity of that incision would, under such circumstances, have become in some degree exhausted : - and on comparing the specific gravity of the sap which bad flowed from a recent and an old incision, I found that from’ ihe old to be reduced to 1.002, and that from the recent one to remain 1.004, as m the preceding cases, the incision being made close to the ground. Wherever extracted, whether close to the ground, or at same distance from it, the sap always appeared to contain a large portion of air. In the experiments to discover the variation in the spe- cific gravity of the albumnum of trees at different seasons, some obstacles to the attainment of any very accurate re- sults presented themselves. The wood of different trees of the same species, and growing in the same soil, or that taken from different parts of the same tree, possesses different degrees of solidity; and the weight of every part of the alburnum appears to increase with its age, the ex- ternal layers being the lightest. The solidity of wood varies also with the greater or Jess rapidity of its growth. These sources of error might apparently have been avoided by cutting off; at different seasons, portions of the same trunk or branch : but the wound thus made might, in some degree, have impeded the due progres of the sap in its ascent, and the part below might have been made heavier by the stagna- tion of the sap, and that above lighter by privation of its proper quantity of nutriment. The most eligible method therefore, which occurred to me, was to select and mark in the winter some of the poles of an oak coppice; where all are of equal age, anid where many, of the same size and growing with equal vigour, spring from the same stool. One half of the poles which I marked and numbered were cut on the 3ist of December, 1803; and the remainder on the 15th of the following May, when the leaves were nearly half grown. Proper marks were put to distinguish the winter-felled from the summer-felled poles, the jpark emg 312 State in which the true Sap of Trees deme Jeft on all, and all being placed in the same situation to dry. In the beginning of August I cut off nearly equal por- tions from a winter and summer-felled pole, which had both grown on the same stool; and both portions were then put in a situation, where, during the seven succeeding weeks, they were kept very warm by a fire. The summer- felled wood was, when put to dry, the most heavy; but it evidently contained much more water than the other, and, partly at least, from this cause, it contracted much more in drying. In the beginning of October both kinds appeared to be perfectly dry, and 1 then ascertained the specific gra+ vity of the winter-felled wood to be 0.679, and that of the summer-felied wood to be 0.609; after each had been im- mersed five minutes in water. This difference of ten per cent. was considerably more than 1 had anticipated, and it was not till I had suspended and taken off trom the balance each portion, at least ten times, that I ceased to believe that some error had occurred in the experiment: and indced I was not at last satisfied till I had ascertained by means of compasses adapted to the measurement of solids, that the winter-felled preces of wood were much less than the others which they equalled in weight. The pieces of wood, which had been the subjects of these experiments, were again put to dry, with other pieces of the same poles, and I yesterday ascertained the specific gravity of both with scarcely any variation in the result. © But when I omitted the medulla, and parts adjacent to it, and used the layers of wood which had been more recently formed, I found the specific gravity of the wmter-felled wood to be only 0.583, and that of the summer-felled to be 0.533; and trying the same experiment with similar pieces of wood, but taken from poles which had grown on a different stool, the specific gravity of the winter-felled wood was 0.588, and that of the summer-felled 0.534. It is evident that the whole of the preceding difference in - the speciiic gravity of the winter and summer-felled wood might have arisen from a greater degree of contraction in the former kind, whilst drying; I therefore proceeded to ascertain whether any given portion of it, by weight, would afford a greater quantity of extractive matter, when steeped in water. Having therefore reduced to srnall fragments 1000 grains of each kind, I poured on each portion six ounces of boiling water; and at the end of twenty-four hours, when the temperature of the water had aa al I foun as deposited during Winters 313 I found that the winter-felled wood had communicated a much deeper colour to the water in which it had been in- fused, and had raised its specific gravity to 1.002. The specific gravity of the water in which the summer- felled wood had in the same manncr been infused was 1.001. The wood in all the preceding cases was taken from the upper parts of the poles, about eight feet from the ground. Having observed, in the ‘preceding experiments, that the sap of the sycamore became specifically lighter when it had continued to flow during several days from the same incision, I concluded that the alburnum in the vicinity of such in- cision had been deprived of a larger portion of its concrete or inspissated sap than in other parts of the same tree; and I therefore suspected that I should find similar effects to have been produced by the young annual shoots and leaves; and that any given weight of the alburnum in their vicinity would be found to contain less extractive matter than an equal portion taken from the lower parts of the same pole, where no annual shoots or leaves had been produced. No information could in this case be derived from the difference in the specific gravity of the wood ; because the substance of every tree is most dense and solid in the lower parts of its trunk: and I could on this account judge only from the quantity of extractive matter which equal portions of the two kinds of wood would afford. -Having therefore reduced to picces several equal portions of wood taken from different parts of the same poles, which had been felled in May, I poured on each portion an equal quantity of boiling water, which I suffered to remain twenty hours, as in the preceding experiments : and | then found that in some in- stances the wood from the lower, and in others that from the upper parts of the poles, had given to the water the deepest colour and greatest degree of specific gravity ; but that all had afforded much extractive matter, though i in every instance the quantity yieided was much less than I had, in all cases, found in similar iniusions of winter- felled wood. It appears, therefore, that the reservoir of matter deposited in the alburnnm is not wholly exhausted in the succeeding spring: and hence we are able to account for the seve- rai successions of leaves and buds which trees are capable of producing when those prev iously protruded have been de~ stroyed by insects, or other causes ; and for the extremely Juxuriant shoots, which often spring from the trunks of trees, whose branches have been long in a state of decay. T have also some reasons to believe that the matter depo- sited in the alburnum remains unentployed in some cases 8 during 314 State in which the true Sap of Trees during several successive years : it does not appear probable that it can be all employed by trees which, after having been transplanted, produce very few leaves, or by those which roduce neither blossoms nor fruit. In making experi- ments in 1802, to ascertain the manner in which the buds of trees are reproduced, I cut off im the winter all the branches of a very large old pear-tree, at a small distance from the trunk; and I pared off, at the same time, the whole of the lifeless external bark. The age of this tree, I have good reasons to believe, somewhat exceeded two cen= turies ; its exttemities were generally dead; and it afforded few leaves, and no fruit ; and F had long expected every _ Successive year to terminate iis existence. After being de- “prived: of its external bark, and of all its buds, no marks of vegetation appeared in the succeeding spring, or early part ef the summer: but in the beginning of July numerous buds penetrated through the bark in every part, many leaves of large size every where appeared, and in the autumn every part was covered with very vigorous shoots exceeding, 1 in the ageregate, two feet in length. The number of leaves which, in T this case, sprang at once from the trunk and branches appeared to me greatly to exceed the whole of those, which the tree had borne in the three preceding sca sons; and I cannot believe that the matter which composed these buds and leaves could have been wholly prepared by the feeble vegetation and scanty foliage of the preceding year. But whether the substance which is found in the al- burnum of winter-felled trees, and which disappears in part in the spring and early part of the summer, be generated in one or in several preceding years, there seem to be strong grounds of probability, that this substance enters into the composition of the leaf: for we have abundant reason to believe that this organ is the principal agent of assimilation amd scarcely any thing can he more contrary to every con- clusion we should draw from analogical rcasoning and com= _parison of the vegetable with’ the anima! economy, or in it- self more improbable, than that the leaf, or amy other organ, should singly prepare and assimilate immediat ely from the ernde aqueous sap, that matter which composes itself. It bas been contended* that the buds themselyes contain the nutriment necessary for the minute unfolding leaves: _ but trees possess a power to reproduce their buds, and the matter necessary to form these buds must evidently be de- rived from some other source: nor does it appear probable that che young leaves very soon enter on this office ; for the * Thomson’s Chemisiry. : expe- as deposited during Winter. 315 éxperiments of Ingenhousz prove that their action on the air which surrounds them is very essentially different from that of full grown leaves. It is true that buds in many instances will veyetate and produce trees, when a very small portion only of alburnum remains: attached to them: but the first efforts of vegetation in such buds are much more feeble than in others to which a larger quantity of alburnum is attached ; and therefore we have, i in this case, no grounds to suppose ‘that the leaves derive their first nutriment from the crude sap. It is also generally admitted, from the experiments of Bonnet and Du Hamel, which 7 have repeated with the same result, that in the cotyledons of the seed is deposited a quantity of nutriment tor the bud, which every seed con- tains; and though no vessels can be traced * which Jead immediately from the cotyledons to the bud or plumula, it is not difficult to point out a more circuitous passage, which is perfectly similar to that through which | conceive the sap to be carried from the leaves to the buds in the subse- quent growth of the tree; and I am in-possession of many facts to prove that seedling trees, in the first stage of their existence, depend entirely < on the nutriment afforded by the cotyledons; and that they are greatly injured, and in many instances killed, by being putto vegetate in rich mould. We have much more decisive evidence that buibous and tuberous rooted plants contain the matter within themselves which subsequently composes their leaves ; for we see them vegetate even in dry rooms on the approach of spring; and many bulbous rooted plants, produce their leayes and flowers with nearly the same vigour by the application of water only, as they do when growing in the best mould. But the water in this case, ‘provided that it be perfectly pure, probably affords little or no tood to the plant, and acts only by dissolving the matter prepared and deposited i in the pre- ceding year; and hence the root becomes exhausted and spoiled: and Hassenfratgz found that the leaves and flowers and roots of such plants afforded no more carbon than he had proved to exist in bulbous roots.of the same w eight, whose ijeaves and flowers had never expanded. As the leaves and flowers of the hyacinth, in the pre- ceding case, derived their matter from the bulb, it appears extremely probable that the blossoms of trees receive their nutriment from the alburnum, particularly as the blossoms of many species precede their leaves; and as the roots of plants become weakened and apparently exhausted, when * Hedwig. they 316 State in which the true Sap of Trees they have afforded nutriment toa crop of seed, we may sus pect that a tree, which has borne much fruit in one season, becomes in a similar way exhausted, and incapable of af- fording proper nutriment to a crop in the succeeding year, And Iam much inclined to believe that were the wood of a tree in this state accurately weighed, it would be found spe- cifically lighter than that of a similar tree, which had not afforded nutriment io fruit or blossoms, in the preceding year, or years. If it be admitted that the substancewhich enters into the composition of the first leaves in the spring is derived from matter which has undergone some previous preparation within the plant, (and J am at a loss to conceive on what grounds this can be denied, in bulbous and tuberous rooted plants at Jeast,) 1t must also be admitted that the leaves which are generated in the sammer derive their substance from a simi- ar source; and this.cannot be conceded without a direct admission of the existence of vegetable circulation, whichis denied by so many eminent naturalists. I have not, how- ever, found in their writings a single fact to disprove its existence, nor any great weight i m their arguments, except those drawn from two important errors in the admirable works of Hales and Du Hamel, which I have noticed in a former memoir. I shall therefore proceed to point. out the _ channels, through which I conceive the circulating fluids to pass. When a seed is deposited in the ground, or otherwise ex- posed to a proper degree of heat and moisture, and exposure to air, water is absorbed by the cotyledons, and the young radicle or root is emitted. At this period, and in every subsequent stage of the growth of the root, it Increases In Jength by the addition of new parts to its apex, or point, and not by any general distension of its vessels and fibres ; and the experiments of Bonnet and Du Hamel leave little grounds of doubt, but that the new matter which is added to the point of the root descends from the cotyledons. The | first motion therefore of the fluids in plants is downwards, towards the point of the root ; and the vessels which appear to carry them, are of the same kind with those which are subsequently found in the bark, where I have, on a former occasion, endeavoured to prove that they execute the same office. In the Jast spring T examined almost eyery day the pro- gressive changes which take place in the radicle emitted by the horse chesnut : I found it, at its first existence, and until it was some weeks old, to be imcapable of absorbin coloure is deposited during Winter. 317 coloured infusions, when its point was taken off, and T was totally unable to discover any alburnous tubes, through which the sap absorbed from the ground, in the subsequent growth of the tree, ascends: but when the roots were con- siderably elongated, alburnous tubes formed; and’ as soon as they had acquired some degree of firmness in their con- sistence, they appeared to enter on their office of carrying up the aqueous sap, and the leaves of the plumula then, and not sooner, expanded. The leaf contains at least three kinds of tubes: the first is what, in a former paper, I have called the central vessel, through which the aqueous sap appears to be carried, and through which coloured infusions readily pass, from the alburnous tubes into the leaf-stalk. These vessels are al- ways accompanied by spiral tubes, which do not appear to carry any liquid: but there is another vessel which appears to take its origin from the leaf, and which descends down the internal bark, and contains the true or prepared sap. When the leaf has attained its proper growth, it scems to’ perform precisely the office of the’cotyledon ; but being ex- posed to the air, and without the same means to acquire, or the substance to retain moisture, it is fed by the alburnous tubes and central vessels. The true sap now appears to be discharged from the leaf, as it was previously from the cotyledon, into the vessels of the hark, and to be employed in the formation of new alburnous tubes between the base of the leaf and the root. - From these alburnous tubes spring other central vessels and spiral tubes, which enter into, and possibly give existence to, other leaves ; and thus by a re- petition of the same process the young tree or annual shoot continues to acquire new parts, which apparently are formed from the ascending aqueous sap. * But it has been proved by Du Hamel that a-fiuid, similar to that which is found in the true sap vessels of the bark, exists also in the alburnum, and this fluid ‘is extremely ob- vious in the fig, and other trees, whose true sap is white, or coloured. The vessels, which contam this fluid in the al- burnum, are in contact with those which carry up the aqueous sap; and it does not-appcar probable that, in a body so porous as wood, fluids so-near each other should remain wholly unmixed. ~ T must therefore conclude, that when the true sap has been delivered from the cotyledon or leaf into the returning or true sap vessels of the bark, one rtion of it secretes through the external cellular, or more probably glandular substance of the bark, and generates a Vol. 22. No. 88. Sept. 1805. xX new 318 State of the true Sap of Trees during Winter. new epidermis, where that is to be formed; and that the other portion of it secretes through the internal glandular substance of the bark, where one part of it produces the new layer of wood, and the remainder enters the pores of the wood already formed, and: subsequently mingles with the ascending aqueous sap; which thus. becomes capable of affording the matter necessary to: form new buds. and leaves. It has been proved in the preceding experiments on the ascending sap of the sycamore and birch, that that fluid does not approach the buds and unfolding Icaves in the spring, in the state in which it is absorbed from. the earth : and therefore we may conclude that the fluid, which. enters into and circulates threugh the leaves of plants, as the blood through the lungs. of animals, consists of a mixture of the true sap. or blood of the plant with matter more re- cently absorbed, and less perfectly assimilated. It appears probable that the true sap undergoes a.consi- derable change on its. mixture with the ascending aqueous sap; for this fluid in the sycamore has beem proved to be- come more sensibly sweet in.its progress:ftrom the roots in the spring, and the liquid. which flows from the wounded bark of the same tree is. also sweet; but I have never been able to detect the slightest degree of sweetness in decoctions of the sycamore wood in winter.. I am therefore inclined to believe that the saccharine matter existing in, the ascend- ing sap 1s not immediately, or wholly, derived from the fluid which had circulated through the leaf in the preceding year ; but that itis generated by a process similar to that of the germination of seeds, and that the same process is al- ways going forward during the spring and summer, as long as the tree continues to generate new organs. But towards the conclusion of the summer | conceive that the true sap. simply accumulates in the alburnum, and thus adds to the specific gravity of winter-felled wood, and increases the quantity of its extractive matter. I have some reasons to believe that the true sap descends through the alburnum as well as through the bark; and I have been informed that if the bark be taken from the trunks of trees in the spring, and such trees be suffered to grow till the following winter, the alburnum acquires a great degree of hardness and durability. If subsequent expen- ments prove that the true sap descends through the albur- num,.it will be easy to point out the cause why trees con- tinue to vegetate after all communication between the nicl an 7 Description of the Coming-up Glass Telescope. 319 and roots, through the bark, has been intercepted: and why: some portion of alburnous matter is in all trees * generated below incisions through the bark. . Tt was my intention this year to have troubled you with some observations on the reproduction of the buds and roots of trees; but as the subject of the paper, which I have now the honour to address to you, appeared to be of more importance, I have deferred those observations to.a future opportunity ; and I shall at present only observe, that I conceive myself to be in possession of facts. to prove that both buds and roots originate from the alburnous substance of plants, and not, as is, I believe, generally supposed, from the bark. Iam, &c. Elton, Dec. 4, T. AnpREw Knicnt. 1804, XLVI. Description of the Coming-up Glass Telescope, as made by Mr. THomas Jones, Mathematical, Optical, and Philosophical Instrument Maker; Pupil of the late Mr. RaMsDEN. As it is of much importance, especially in war time, du- ring the chase of a vessel, that the chasing ship should be able to ascertain whether she lessens or increases her di- stance from the object of which she is in pursuit, [am per- suaded the philosophical world will be pleased with a de- scription of an instrument adapted to this useful purpose, invented by the late Mr. Ramsden. | It consists in applying a micrometer to a refracting telescope of about two feet long, or to a day and night telescope ; and J have been in- formed by some who were furnished with them by Mr. Ramsden, (and by myself since his death,) that they an- swer the purpose remarkably well. To this combination the English sailors have given the name of a coming-up glass. ‘To fit the telescope for this use, the third glass from the eye, in the drawer of the tele- scope, is divided in two by cutting it across its centre at right angles to its surface; and, in using it, these two semi- lenses are separated from each other in the direction of their line of separation. By turning a finger-screw on one side _ * Ihave ina former paper stated that the perpendicular shoots of the vine form ati exception. 1 spoke on the authority of numerous experiments ; but they had been made late in the summer ; and on repeating the same experi- ments at an earlier period, I found the result in conformity with my experi- ments on other trees. : X2 of 320 Description of the Coming-up Glass Telescope. of the eye-tube, each semi-Jens forms an image of the same: object. These two images will be mote or Tile saponaeet in the proportion of the distance of the centres of the semi- lenses from each other, whiel: distance is shown in revolu- tioiis and parts of a revolution of a finger- screw that sepa- rates them. For this purpose a‘circular head is fixed on the finger-screw, the cdge of which is divided into a hun- dred parts ; and in order to know the number of tevofutions, a smallslip of brass (that passes over the gtaduated surface of the héad; ‘and serves as its index for showing the cente- Simal parts of’ a revolution) is fixed to the eye-tube, and has its chainfered cdge ‘also divided, each division being équal to one entire revolution of the screw. : Yo adjust the Telescope. Having, by drawing out the eye-tube more or less, ad justed the telescope to distinct vision, turn the finger-screw till the-two-images of the same object-appear in one, and the edge of the head together with the division numbered 100 will be found.at the first division on the index that shows the -reyolutions, . . The use of the Coming-up Glass. Having directed the telescope to the vessel chased, turn the finger-serew till the two images of some well defined part... of the vessel appear to have their extreme edges in contact with each other; then read off ‘the number of revolutions of the screw shown on the chamfered ‘edge, also the parts of a revolution shown on the cdge of the head-: then if, after some time, it be required to know whether we have gained or lost in the chase, again bring the edges of the images of the same object in contact as before. Hf the number of revolutions and parts of the screw be the same as was show? before, we have neither gained nor lost in the chase. But if the number of revolutions and parts he Jess, the distance from the chased vessel will be greater in the proportion of the difference of these numbers ‘to the former. On the contrary, if the number of revolutions and parts be greater, we come nearer the vessel in the proportion of the difference of these numbers to the number of revolutions and parts of the first observation. Example. ; 5 shh. oe ila. : RpAr be Suppose in the chase of a vessel, by turning the finger- screw, 1 bring the image of the main-top-yard to coincide with the main-yards and, reading off the value, I find it to be three-revolutions on.the chamfered edge, and 20 parts of arevo- On the Buds and Ramifications of Plants. 321 a revolution on the circular head, which may be wrote 390; if, some little time “after, hy bringing the two images of the same object in contact, I find the aumber of revolutions and parts to be 360, the difference of the two observations is 40, therefore 40.: 320 ;: 1: 8 (that 1s, 40, the difference, is ta 320, tue. first observation, as ] is to.8); consequently, we shall have gained in the chase one-ejghth.part.of the, di- stance: but if at the second observation the number.of re~ volutions be less, for instance 280, or two.revolutions and 80 parts of a revolution; then, as 40, the, diierence,. isito 320, the first observation, so is 1 to 8: consequently we should have lost one-eighth part of our distance 1n the chase. No. 120, Mount-street, / : ; r Berkeley-square. . >» 9 oe XLVIT. On the Buds and Ramifications of Plants ; the Birth of these Organs, and the organic Relation between the Trunk and. the Branches: in a Letter from G.L. - Korver, Jf. D. Professor of Botany and the Materia Medica in the Provisional, School of Medicine at Mentz,. to M. Ventenat, Member of the French National Ih* stitute, Bre ie [Concluded from ip, 241.] Bor it may be said, if these observations on the origin of buds are founded in nature, how comes it to pass that. herbaceous and so tender bodies should penetrate through. a cansiderable number of ligneous- zones, which. must,be the case in branches. of two or three years of age, which, though rarely, produce, however, sometimes buds? It ap- pears to me very probable, that at the period when the lud becomes expanded, a period which corresponds. with. the elongation of the medullary sheath, a certain number of the bundles of the tubes of that sheath proceeds laterally from interval to. interval towards the bark. Soon after, the first cambium, of the bud appears between the medullary sheath and the bark, and separates these two parts from, - each other. This cambium does not Jong retain its muci-. laginous form; it is soon metamorphosed into the first Ziler _orbark. The bent vessels of this first liber, in hardening and becoming every day straighter, proceed towards the medullary sheath, round which they compress themselyves,, and form there the first allurnum, which becomes then the first ligneous zone. The prolongations of the medullary sheath are not all pinched by the formation of this first . stratum 322 On the Buds and Ramifications of Plants, stratum of the wood; for the latter quits its mucilaginons state slowly, and its tubes have not straightened themselves by a great effort: on the contrary, they retain their curva- ture around the prolongations, as may be readily seen. The straightening, however, and compression of the tubes of the liber one against the other, ought to be attended with this necessary consequence, that the prolongations should be more or less pressed; and as this is repeated every year in the formation of the new ligneous strata, the result must be, that not only a certain number of prolongations are at length stifled, but also that the quantity increases in proportion as the twig becomes a branch, and as the latter acquires more size. - This opinion appears to me to be very well founded, for we observe that the number of the buds is generally in the inverse ratio of the age of the branch: nature will have it that this number should decrease more and-more every year, and she fixes a period at which branches generally ecase altogether to produce any. On ‘this rule, modified according to the nature of each species of vegetable, and according to- the particular circumstances under which the plants are placed, depends in a’great measure the habitus of the vegetables. Nature rarely deviates from this law: there are, however, some exceptions; and it sometimes happens that it retains,in case of need, some of these prolongations, which have not expanded into buds during the first years of the branch. If, for example, the sap rises in too great abundance, or if it be too nourishing, especially when the tree cannot sufficiently discharge it, such of these prolonga- tions as are not stifled acquire vigour, lengthen themselves towards the bark, pierce it, and give birth to gluttonous branches, or branches with false wood, which often preserve the tree from plethoric diseases which might become mortal, The birth of these twigs explains to us,in my opinion, why the buds from which they have been produced are always thin and herbaceous ; why they almost always expand very speedily, and often out of season; and why they do not adhere firmly to the tree. It appears besides, that my opi~ nion on the question itself is confirmed by the considera-: tion, that if nature forms more wood than usual, and very thick zones, the branches commonly give. fewer buds the following year: but nature seems then to gain on the one hand what it loses on the other; forit multiplies then the nurober of the young branches, which, as we know, produce ‘ more buds than any other part of the vegetable. Another observation, which renders my opinion still more probable, is, that I have seen at the lower part of the branches, ane the On the Buds and Ramifications of Plants. 328 the twigs of several trees and shrubs, such as the young branches of the common willow (salixceprea), a considera+ ble number of small herbaceous prolongations of the me- dullary sheath, which were as insulated and dispersed throughout the ligneous body, and which had neither pierced nor raised up the bark that covered them. They appeared to me to be prolongations reserved to form, in case of need, leaves or branches. But how can we account for the origin of buds from a trunk the interior part of which is rotten, and where the medullary sheath no longer exists? and how comes it to pass that the branches of a hollow tree, or those grafted on another tree, vegetate with the greatest vigour? It appears to me that the answer to this question presents no difticulty. These phenomena will soon be explained,it we shall be able to prove that the prolongations of the sheath may be pre- served, and live, when they are separated by art or by nature from the sheath whence they have arisen. In these cases the branches nayst receive the sap by other tubes than those of the sheath. But does not the observation made by Coulomb, that mi sound trees the sap ascends chiefly by the tubes which surround the pith, oppose what I have said? I do not think it: on the contrary, I am of opinion, that, if the observation of that celebrated philosopher had still need of being corroborated, it certainly would be by my experiments on the prolongations of the sheath. It is in these organs indeed, more than in any other, that we are to search for the proof that the sap ascends chiefly in the vessels of the medullary sheath of a sound tree, because when cut transversely they are always found, as longas they are not ligneous, more or less filled with juices. But is the medullary sheath the only way by which the sap proceeds from the root to the extremities of the vegetable? Has na- ture confined herself within so narrow limits, or has she established other canals to conduct the nourishing juices from the root to all the ramifications of the plant? The existence of so many hollow trees will furnish us with an answer. In hollow trunks it 1s only by the /iler, and be- fore the birth of that organ by the a/burnum, that nature makes the sap to ascend. It happens also, but more rarely, that the bark is provided with small tubes which convey a part of that limpid liquor. If we examine the hollow wil- lows on the approach of spring, it will be observed that the allurnum is full of juice. If we cut the stems, branches, and stalks of the vine, euphorbia, &c. we shall see the tubes next the bark emit not only their own juices but also an Xx 4 aqueous 324 On the Buds. and Ramifications of -Plantss aqueous humour, which is the ascending sap. The liber, adburnum, medullary sheath, and sometimes the tubes of the bark, are the only organs which nature employs in the. rotyledons to convey the sap to the ramifications of the trunk. But after the sheath has produced the prolonga- tions.or germs of the buds, the liber and alburnum secure in preference the preservation of the individual ;: for, when the new production of these organs is prevented, the'plant infallibly dies: on the other hand, if nature destroys. the sheath, the tree very often vegetates as before; and to be fully convinced of it we need only mention the enormous boabab of the coast of Africa. Besides, the ingenious ex- periments of Mirbel have fully shown how, by the help of the pores and fissures with which almost all the tubes and cells of vegetables are pierced, the sap may be conveyed to all the parts; and how nature, to conyey the juice from one organ to the other, may find ways which to-us appear extraordinary. Hence we are obliged to believe, that in the case where the sheath does not exist, or a graft has suc- ceeded, and where the pith is converted into wood, the prolongations may receive the nourishing liquor with which they are filled, from the living tissue with which they are in immediate contact. In plants, even the interior part of: which is very sound, the sap cannot be conveyed imme- diately from the tubes of the sheath of a trunk to those of the sheath of an old branch. In this case, the prolonga- tions are not composed of tubes; they have become entirely ligneous, and their vessels, changed into fibres, no longer convey the juices. There is no longer any organic com- munication but by means of the alburnum, the liber, the medullary radit, aud the bark: even the latter rarely serves for conveying the sap.. It thence follows, that the sap.of the trunk ascends in the sheath, passes thence into the liber, or the alburnum, to be conveyed tothe sheath of the branch through the celluJar and vascular tissue. When it reaches the sheath of the branch, it is conveyed to the fol- lowing ramification in the same manner as from the trunk, to the principal branch. The origin of buds, of which I have spoken, enables us to conceive the cause® of the firm insertion of the branch into the trunk. The bud has been produced by a prolonga- tion of the medullary sheath: the first stratum of the wood is formed while that bud has been elongated into a branch : | the trunk has produced one at the same.time; the ligneous zones have succeeded regularly from year to year in the trunk and m the branches, and each zone of the branches 18 On the Buds and Ramifications of Plants. 395 is in an uninterrupted relation with another zone of the | trunk, and seems to be thus produced by the prolongation or increase of the latter. It appears to me that the cause is explained by the following observation :—It is generally known that the cambium, of which the liber is formed, has its birth in the alburnwm and bark, and that the latter, during the formation of the cambiwm, is altezether sepa- rate from the alburnuwm even at the base of the branch. By these. means the camliwm of the trunk and that of the branch are never divided; on the contrary, they adhere to each other, and the resuit is, that the: wood. thence arising forms thus-an uninterrupted zone. The old trunks of the pine, fir, oak, &c. seem) however, sometimes to show the contrary; for itis not uncommon that the-branches, even those covered with bark, traverse a greater of less part of the wood of the trunk, without being there united to the exterior zones. Nevertheless, if such a trunk be cut vertically, it» will be seen that all the zones of the branch have an im- mediate reference to as many zones of the trunk ; the reason of which is, that this branch has been cut, or has ceased to. grow, and that the trunk, which has continued its zones, has surrounded and inclosed the branch sometimes even en=- tirely. - It may perhaps be asked, why all the germs of a twig do not pierce the bark at the same time the first year. This question I am not able to answer, because I cannot unveil the mysteries of nature, and, in regard to the.birth of buds, know only the above phenomena. It may, however, be conjectured that in the expanded buds there were germs, that is to say, prolongations of the medullary sheath, dit- ering in size and vigour; and that, besides, the time of their respective development depended on external circum- stances, the most of which are still unknown to us. It is observed sometimes in shumac, the plane-tree, &c. that the lateral prolongations are entirely dried and ligncous, though that in the middle he still perfectly herbaceous. In this case the petiole which covered the great prolongation, and below which the bud that produces the twig must have been formed, has been torn or dropped off the preceding spring, or at least before the aritumn. The means which nature has made choice of to-nourish the buds during the wintef have been the object of several hypotheses. | shall abstain from mentioning them all, in order that | may attach myself to the only one which merits particular consideration, The interior of the bud has been compared to the embryo of a seed, and it has been aint toat 326 On the Buds and Ramifications of Plants. that the body of this bud: was nourished by the scales which cover it, as the embryo is by the cotvledons. I shall not here examine whether the embryo be really nourished by the cotyledons; but I must deny that the bud is nourished by the scales, sometimes very arid, which protect it. On the contrary, it is nourished by the juice conveyed to it by the prolongations of the sheath; for I have bad opportini- ties of remarking that the motion of the sap does not en- tirely cease in the interior of the tree but when the cold is severe, and the buds are then preserved without having need of nourishment. To insure the conveyance of the sap to the buds, and by these means to shelter them as much as possible from the cold, nature, perhaps, has caused the pro- longations of the sheath to be traversed by one or more zones of wood. In regard to the symmetry which nature exhibits in the disposition of the prolongations of the sheath and the buds, it is as yet inexplicable to us: the hypothesis that the bud pierces the bark at the place where it 1s thinnest, as for ex- ample in the eves of the leaves, is still very far from the truth, The question is, to know how the prolonged tubular bundles of the medullary sheath which is directed towards the bark, may meet that thin place without having crept along the interior side of that organ. A thousand other questions might be added, which present difficulties equally great. It appears to me very probable that Hales, Linnzus, and several other observers who had adopted the hypothesis that the pith is the most active organ in the interior economy of plants, the reproducing organ of the ramifications of the trunk, were not far from discovering the tubular pro- longations of the sheath, which I discovered by chance. It appears to me also that the green substance contained in the medullary sheath has a different origin from that ascribed to it; and that in regard to the medullary radii, to which Daubenton has given the name of medullary prolongations, they are very different from the organs to which I have given the name of prolongations of the sheath. My researches in regard to these organs have made me perceive also some phenomena respecting the origin of leaves, which were entirely unknown to me. These-organs are considered-as expansions of the herbaceous tissue of the bark, and of the tubular tissue of the lider. This opinion is among the number of those which cannot be admitted. A leaf, whatever be the place of its insertion, can never he torn of without finding, exactly at the place where ‘ ig xed, Progress of Vaccination in India. 327 fixed, one or more prolongations of the medullary sheath penetrating the wood, and sinking into the petiole, or into the base of the leaf to which they convey sap. In the sper cies of the family of the pinnifera one single prolongation of the like kind enters into the petiole: in all the other vege- tables which I have examined, I found two, three, and even more. ' The fall of the leaves is explained, not only by the in- fluence of the air and the sun, but also by the mechanism of nature, which, according to the opinion most generally admitted, prevents the sap from ascending from the branch to the petiole. - “© The tubes of the /iler (it is said) in daily extending more press against each other, and by a necessary consequence transport themselves towards the centre of the vegetable ; at the same time the bark, which diates itself, recedes; and the necessary result of these two, movements is, that the leavés tio longer receive sufficient nourishment.” There is no doubt that the mfluence of the air and the sun contributes powerfully to harden the substance of the leaves, as well as to approach towards the ligneous state, in which the passage of the juices ceases, and then the leaves no longer transpire or absorb. But Ido not believe that the mechanism in question can in any manner prevent the ascent of the sap. But do we not, indeed, see that in a great number of plants some leaves drop at the period when the liber has not yet been changed into. aléurnwm, and while the sap is still in full motion? {In a word, when the bark is separated at the place where the petiole has been fixed, it is seen that the prolongations of the medullary sheath, which have conveyed the nourishing juice from the stem to the leaves, are still green and herbaceous, and have suas- tained no injury; which seems to prove that they were not choked, nor attracted with force. They dry a long time after, and acquire very slowly the consistence of the wood in which they are placed. ; XLVIII. Progress of Vaccination in india*. Never was a discovery corroborated by more numerous and distant evidences than the cow-pock. The bramins in India were accustomed to inoculate at ‘certain periods of the year; now they vaccinate throughout the year ; and the following testimony has appeared in the * Communicated by Dr. Thornton, - government 7 328 = New Genus of Manwnalia called Hydromis. aS: gazette at Fort St. George, Dec. 19, 1804, eing a letter trom the head bramin to the physician-general at Madras, To Dr. James Anderson. a SIR, I beg g leave to assure you that I am an eye-witness, as well as many other bramins, of that wonderful, healthfal, immortal vaccine matter, discovered on the nipples and adders of some cows in England by that illustrious doctor, Jenner; whereby that Joathsome, painful, and fatal small- ox has been prevented attacking persons in India as well as in England, Numbers of children and others have been inoculated by us without any injury whatever, except a small blemish or spot in the place where the matter is ap- plied, generally on the arm. This preserving power should be experienced not only by the honorary but also those of the low cast. On which account permit me to observe, that the term cow-pox, adver- tised in our Tamul tongue by you, translated comary, should be altered, not to give room for the prejudices of the very commicn people ; and it should be styled, no doubt, a drop of nectar from the exuberant udders of some cows in Eng- and, and not by any appellation similar to the humour discharged from the feet of diseased cattle in this country. I am, sir, with much respect, Your faithful, obedient, very humble servant, Dec. 19, 1804. Moo-PE-RAL STEE-NE-VA-SA-CHA-RY« XLIX. Memoir on a new Genus of Mammalia called Hy- dromis. By E. Georrroi (Saint-Hivarge).* Tus new genus, introduced into the system, is. com- posed of three species, two of which have never been described, and the third cannot be exactly known but by means of the illustrations which | am about to give. It was first found in the waters of Chili by Molina, who pub- lished am account of it under the American name of coypow : it has since been met with only by Felix d’Azzara, who has given a long description of itt under the name of quouyia, by which it is known in the province of Tucuman. A Jong time, however, after these travellers had disco- vered the coypou, it had engaged the attention of Commer~ * From Annales du. Muséum d'Histoire Naturelic, No. 31. + Histoire des Quadrupedes du Paraguay, vol. ti. art. 2. New Genus of Mammalia called Hydromis. 299 son; and it would then have been more perfectly known, had that respectable and indefatigable naturalist lived long enough to publish the immense-materials with which he enriched natural history. There was found, indeed, among Commerson’s papers, a drawing of this singular animal re- duced only to lialf its size: he had been indebted for it to s° M. Bougainville de Nerville, governor of the Malouine Islands, an enlightened amateur of natural history.””. These are the words ot the note which our respectabie correspou- dent put at the bottom of the drawing which had been given tohim. The name myopotamus Lonariensis, which he pro- visionally gave to this species, proves that he then consi- dered it as the type of a new genus. I have not employed the same denomination as Com- merson. It appeared to me more proper to prefer that of hydromis, composed nearly of the same radicals, because it presents the same termination as the names already em- ployed to denote the most of the analogous genera, such as those of pteromis, phascolomis, lagomus, cheiromis, &c. We long neglected the drawing of the myopotamus, either because, not haying been executed by Commerson himself, it did not inspire us with sufficient confidence, or because our mistrust was authorized by the difficulty of comprehending it in the genera already established. It was only after examiming the rich collection of furs of M. Bechem*, where I found a considerable quantity of the skins of an animal which appeared to me to be unknown to naturalists, that I recollected the drawing of Commergon. M. Bechem informed me that these skins had been intro- duced into commerce about nine or ten years before; that they were transmitted by the way of Spain; that he never received fewer than a thousand at a time; and that in some years the number amounted to fifteen or twenty thousand. M. Bechem found that they had an affinity to the beaver skins, and could be applied to the same purposes: he sold them under the denomination of racounda, which he derived from that of racoon, the name given by the English to an animal of North America. They are’ sought for in com- merce, and are employed in particular by the manufacturers of hats. Thus our arts were supplied with, and a part of our dress was formed of, the hair of an animal with which we were unacquainted, and which, however, was sufficiently different from others of the same genus to deserve to be elassed in a small particular tribe. a Jt was so humiliating a condition for science to be thus ay outstripped * A fur-merchant of Paris. 330 New Gems of Mammalia called Hydromis. ; | outstripped by commerce, that I could not help embracing the ea peeat opportunity of endeavouring to discover to what animal this useful far belonged. Amone the number of skins which M. Bechem possessed, I had the good for-. tune to find a sqfiicient number entire, to enable meto hope that I’should be able to determine this point. I -soon per- ceived that the description of the quouyia of M. d’Azzara sidan ey to them perfectly, and that this description could be exactly apphed also to the drawing of the myopo- tamus. should have been sooner conducted to this com- parison, had | not. found, in the French translation of M.d’Azzara’s work, the epithet of red twice substituted for that of ruddy: the author, by the Spanish word rabro, had denoted only the latter quality. It was with reason that Commerson had provisionally considered his animal of Buenos-Ayres as a new genus $ it belongs to the order of the rodentia by its two strong incisor teeth in each jaw; but not to any of the genera of that order, in consequence of its tail and its’ hind feet. The conjecture of Commerson is now fully justified by the ex- istence of two other species in New Holland, which have exacily the same combinations of form: such are the three animals which I comprehend under the same generic deno- mination of hydromis. To be able to subdivide with "more precision the order of _ the rodentia, and particularly the numerous genus of rats, we have attended to the consideration of the molar teeth, the form of which has furnished us with excellent charac. ters, which have gone hand in hand with the different con- figurations of the feet and the tail. Thus, all the rats ana- logous to the field rat, the water rat, &c. have the molar tecth formed of lamin placed one before the other, and the tail short and hairy: on the other hand, those which have a relation to the common rat, &c. Norway rat, &c. are distinguished by molar teeth with a simple crown, and by their long tail, which is in part naked and scaly; others, such as the hamster, have these teeth single, and the tail short and hairy. My first care, after these observations, ought to be to at- tend to the molar teeth of my three species, and deduce from them characters applicable only to them. I was de- prived of the means of doing this in regard to the American species.. M. d’Azzara neglected to “speak of its molar teeth: Molina, however, has in part ausened this defi- ciency, if it be true that he extended his remarks to their number. We have reason to believe this from the extract ”~ ‘ in New Genus of Mammalia called Hydromis. 331 im regard to the mus coypus, which Gmelin made from the account of that jesuit. M.Gruvel in the French transla tion must, then, have omitted this important character, However, the following are the observations, in recard to the teeth, which I made im the two species of New Hol- land. These molar teeth present themselves first in a number worthy of remark : there are only two on each side, which carries the whole number to eight. Their form exhibits no less singularity: the length of each is double its breadth - the enamel traverses it in the middle, turning round in such: a manner, that the section forms pretty nearly the figure 8, which is rendered sensible in particular by two excavations, pretty deep, corresponding to the vacant spaces which exist in that figure. The feet of the hydromis have five toes ; those of the fore feet are very short, and almost entirely enveloped: the other toes are free. On the other hand, those of the hind feet are engaged in a membrane: the external toe only is at liberty, because the general membrane which extends over it, and which borders the interior side, arises only from the extremity of the metacarpian bone of the annular toe; it forms on the last a small interior border, which does not retain it in its deviation. The nails are compressed, pretty long, hooked, and very sharp. The head, as far as could be judged from. the remains which I examined, is broad and depressed like those of the beayer and the water-rat: the muzzle appears to be less obtuse; the neck is thick and short; the ears small and round ; the whiskers long and thick. The hair is of two kinds, as im the beaver ; under the long silky hair is a short felt, thick, and exceedingly fine. The hydromis has a resemblance also to these animals by the proportions of its body, and particularly by the short- ness of its paws; but they differ sensibly by the form of the tail, which is almost as long as the body, perfectly round, and terminating in a. point. In general, there can be no doubt that in the naturah order these animals ought to occupy an intermediate place between the beaver and the water-rat: being destitute of membranes on the hind feet, they would naturally belong to the tribe of the latter; or, if their tail had the form of that of the beaver, they might be united with the species of that genus. ist, The Hydromis Coypou.—I have said that it was first: made 332 New Genus of Mammalia called Hydromis made known by Molina. His des scription comprehends pretty well the essential points, but is not sufficiently mi~ nute. This traveller speaks of the coypow asa species of water-rat, of the size and colour of an otter. Gmelin has confined himself, in what he has said of the mus coypus, to copying Molina. M. d’Azzara, on the other hand, has given a complete description of that species, with:the mea- sures of the different parts of the body; and, in general, has not omitted what relates to the molar teeth. The coypow is distinguished in particular from the two other species, of which we shall speak’ hereafter, by its great size. Ta. Lines. Length of the body - = -» 9 ofthe tail - -' = - 2) of the heads - - = 4 3 of the extremities - - 4 The general tint of the hair and on the back is a chestnut brown. This colour becomes brighter on the flanks, and passes to bright red ; under the belly it is only a dirty and almost dark russet. y et this colour is sufficiently change- able according to the manner in which the coy por raises Or lowers its hair. This mobility in the tone of its fur arises from each hair being of an ash-coloured brown at the root, and bright red at the point. The felt concealed under the long hair is an ash brown, of a brighter tint under the belly. ” The long hair on the back has the points only reddish, and that on the flanks is of the latter colour throughout the half of its lengths As in all animals which 20 frequently into the water, the hair of the tail is thin, short, stiff, and of a dirty red colour; in its naked parts it is scaly. The contour of the mouth and extremity of the muzzle are white; the whiskers, which are long and suff, are also white, some black hairs excepted. Among the great number of skins which form part of the collection of M. Bechem, I saw some belonging to ani- mals which had no doubt been affected with the albine dis- ease ; in one of these the silky hairs were entirely russet, so that the back appeared of the same tint as the sides and the belly ; in another, the grand dorsal stripe, instead of being chestnut, had passed entirely to a red colour, the flanks being of a very pale red.’ I cannot believe that these varie- ties, on the one hand, were the character of youth or of the female, because these accidents were rare, considering the / great New Genus of Mammalia called Hydromis. 333 great number of skins which J examined ; and on the other, because M. d’Azzara has expressly told us that the female is entirely similar to the male. Molina and d’Azzara agree in regard to the mild qualities by which the coypou is distinguished. It eats every thing given to it, and seems to attach itself to those who take care of it. It may he easily tamed, and soon becomes accus- tomed to the state of domesticity. It is never heard to cry but when harshly used ; it then emits a piercing cry. The female produces five young, which she always carries with her. The coypou is very common in the provinces of Chili, Buenos-Ayres, and Tucuman. On the other hand, it is rarely found in Paraguay. ad. The yellow-bellied Hydromis —This species is nearly half as small as the coypou. The length of its body is one foot, and that of the tail two inches six lines. Its tong hair. is not sensibly distinguished from the felt 5 it is proportionally shorter and finer, which renders the fur of this hydromis more valuable than that of the coypou: there are few furs thicker, or softer to the touch. The hair in its apparent part is above of a chestnut brown, and below of a most beautiful orange colour. At the root it is ash- coloured, and gray under the belly. The tail is entirely covered with very short and stiff hair: towards the root it is pretty large, and well furnished ‘vith hair: in three- fourths of its length its colour is the same as that of the back; but in-the other fourth, towards the poimt, it 1s of a very pure white. The membrane which incloses the toes of this second species is not so extensive as in the coypou ; its interior cut is a little deeper. This animal was killed by a sailor in one of the islands which form d’Entrecasteaux’s channel, at the moment when about to shelter itself beneath a heap of stones: it was preserved to us by the care of M, Levillain, one of the zoologists on the expedition to the austral lands. 3d. The. white-lellied Hydromis.—This species has a great resemblance to the preceding, and is of the same size. Tis head, however, is a little longer, and its fur not so fine, and less soft to the touch. The hind-feet are only half palmated ; its hair is brown above, and dirty white below. The tail is also terminated with white, but for a more con- siderable extent : the white part forms a little more than a third of the whole length. Four individuals of the white-bellied Hydromis were transmitted to us, all of which had a great resemblance to Vol. 22. No. 88, Sept, 1805. 4 each ‘334 Experiments on the Hand Granade, each other: they were found in the island Maria, which is not far from d’Entrecasteaux’s channel, by Messrs. Peron and Lesueur, to whom we are indebted for almost the whole of the zoological riches brought to us from New Holland. I have comprehended in the following table all the cha- racters of the genus and species of these three animals. HYDROMIS. Nar. cxar.—Incisor teeth two in each jaw ; canine; two molar teeth in each row, furrowed on the side, and with a double excavation on the crown. Feet pentadactyles ; the anterior free, the posterior pal- mated. Tail round, and covered with short hair. Essent. cHAR.—Flind-feet palmated. Tail round. I. Species. Hypromis covrov. Hydromis coypus (Plate VI.) . Hair chestnut brown on the back, red on the flanks, and bright brown under the belly. Coypou. Molina’s Hist. Nat. du Chili, p. 255. French ‘Franslation. Mus coypus. Gm. Syst. Nat. Quoiuy2. D’Azzara, Hist. des Quad. du Paraguay, tom i, pel. Country.—Chili, Paraguay, Tucuman. If. Species. YELLOW-BELLIED Hypromts. Hydro- mis chrysogaster (Plate VIII.) Hair chestnut brown above, orange below. Shite Se of the islands in d’Entrecasteaux’s chan- rely Ill. Species. Wuite-Bevuiep Hypromris. Hydro- mis leucogaster. (Plate VII.) Hair brown above, white below. Counraxy.—tThe island Maria. L. Physico-mechanical Experiments and Discussions of the Phenomena observable mm that casual Product of Art the Hand Granade, Prince Ruperi’s Drop, or Glass Tear... By Mr. Joun Snarv, Optietan. Aurnover the subject of this paper is very inconsiderable in itself, being, as was said above, ‘ the casual and easy product of art ;”’ yet as it tends, in my humble opinion, te: develop some very obscure and important phenomena in nature as well as the arts, I shall not take an operose route to apologize for offering my explanation of it to the public ; because ‘every accurate account of the arcana nature, &c.. is / Prince Rupert’s Drop, or Glass Tear. 335 is always sufficient to justify itself, and consequently does not neéd any apology. I therefore proceed. The pyrometer long ago has demonstrated to the satis- faction of every one in the least acquainted therewith, that all bodies, whether in a fluid or solid state, expand by heat, and contract by cold, and from a very obvious cause; viz. because the particles of that fluid element, (fire,) by insi- nuating themselves between the component parts of such bodies, not only fill the most minute interstices, and per- vade every pore with the greatest facility, but absolutely dis- unite or separate the constituent particles themselves, and thereby make them, in the aggregate, of a greater volume ; and ultimately render such substances (if capable of fusion) a fluid, or running mass: in which state such substances occupy thcir greatest possible extension,—unless they were yolatilized, or changed into vapour. . Thus much for the laws of fusion themselves. The ap- plication and inferences from them are quite appropriate. It is while the greatest possible degree of expansion of the vitreous matter exists, that the portion which formis this molten tear or drop I am about to treat of, is separated and made. In fact, its fusion is the radical consequence of its extreme rarefaction, or expansion, being physically and me~ chanically superinduced thereby. For, by the introduction of the accumulated igneous particles, a separation of the once continuous particles of the glass takes place, until the attraction of cohesion entirely ceases, and fluidity eventually ensues. Now, at this instant of extreme excitation it 1s, that, with a sudden and forcible jirk, the artist ejaculates or throws it forth to be suddenly quenched in cold water ; when it is evident, that the parts which first came into contact with the water will become cooled and indurated firsts—which igs the exterior surface. And this stratum (if 1 may so speak, and suppose the whole composed of a number of strata) having taken its form and dimensions, no internal mutation or exertion it is capable of can either alter or lessen its form. But as all bodies, as was said before, must contract in cool - ing, the interior parts (contrary to gradual cooling) must give way: they therefore become vacuous, of necessity. And because the central parts cannot coalesce, they being the last which feel the refrigerating quality of the water, they remain longest in a fluid state: and as there is nota sufficient quantity of matter, when cooled, to occupy. all the space it did when in an ignited or rareficd state, the parts which are most fluid, being most easy to move, and ’ ° Y 2 finding 336 Experiments on the Hand Granade, finding they cannot fill the whole space, by close anion, on account of their paucity, make the best junction they can, by taking a lateral course, and a vacuum is the result of unavoidable necessity. Aad such a vacuum as cannot be produced by any other means that we know of ;—a vacuum only assailable by that subtle agent that knows no impediment, But walks alike through solid gates of brass, Oz bars of steel, or doors of molten glass 5 \ This prima motile all forms pervades ; Our ev ry act depends upoa its aid. It is true, the same event happens to other bodies, upon being brought into a state of fusion and suddenly quenched, as to glass. Thus, if a bar of steel be overheated in our attemipts to harden it, we see upon breaking it that the in- terior parts have changed their position, and formed them- selves into.a kind of irreaular crystals, for the same reasons : yet, as no substance but glass is so generally impermeable to all agents, except fi fire, the result is not so satisfactory as when this material is used ; because, on account of its diaphanous nature, or transparency, ‘the appearances are more ocular, cousequently less doubtful. For bere, with- out analogy or hypothetical inference, our senses are called to witness the most complete vacuum in nature; and, as far as relates to heterogeneous effluvia, quite perfect. A vacuum not of the Boylean kind, where that air which is driven out is ejected “by means of that which re- mains behind; but of the Torricellian kind, yet infinitely more pertect : the very formation of which precludes the possibility of the most subtle agent in nature (except fire) insinuating one particle of its - substance therein. And, were it possible that we could make this vacuum subsér- vient to our experiments on the mechanical pressure of the air, (whether incumbent or lateral,) I am persuaded, from what I have herein discovered, Gat we should have a greater result than (the maximum allowe d) 14 or 15|bs. per inch for its energy. The excess of which energy would be ina direct ratio to the perfection of this vacuum, in comparison with that of the barometer: and those of the air-pump cannot stand one moment in compeution, fer the reason assigned above. - And yet so well grounded were the'antient philosophers “in all space being occupied by some agent or other,” that they have, as it were, anticipated us in our most modern discovery ; for it was one of the dogmata of the Peripate- tic or Aristotelian schools, “ that Nature abhorred a va- Ps cuum.” Prince Ruperi’s Drop, or Glass Tear. 337 cuum.” And although I will not take upon me to justify all their decisions, or even this dogma itself upon their principle; yet as this seems the ne plus wltra of Iman means to procure one, and which, after all, appears not to be absolutely so, I] think their assertion ts not remote engugh from truth to justify a rash contradiction on our part, or to arraign the profundity of their knowledge. Bat to return: How great must be the velocity, how great the mechanica! collision, to rend asunder with such force so well compacted a substance as the glass of which these granades are inade, even after making every reasonable allowance for its want of annealing, which no doubt in- creases its fragility, while it hardens the surface! There must be something more than mere mechanieat influx, or consequent collision, to rend asunder and reduce to powder an impregnable mass, which is capable of resisting the weight of many tons, sustaining the force of a large vice, or the rude strokes of a hammer’ (after allowing for the gcometric resistance on the external attack, and the want of the same in the internal force) used in breaking them, he- fore this phenomenon will be satisfactorily explained. And without giving a more elaborate definition than the thing is obviously susceptible of, f conceive this cause to be electricity : and that, in the formation of the drop, after the caloric particles have pervaded the glass and subsided, this matter, like a lambent flame, attaches to and hnes the inte- rior surface or cavilics, as in the Leyden jar; and by this hermetic accident (for it is not properly art} may remain prisoner for many centuries ; but yet, though pent up, (being perfectly msulated) 1s not diminished: therefore, upon ~ opening the conduit pipe of communication in the tail, the affinity the iclosed effluvium has with that in the air, our hands, or whatever else breaks them, ¢auses that violent de+ tonation, and the destruction thereof considered therewith to take place, and the force of the explosion is (ceierts parilus) in a compound, direct, ratio with the capacity of the cavi- ties, and the streneth of matérials. Thus ts is, when a vacuum ts induced of necessity, and of materials which, while they are extremely friable on the one hand,. are impervions to both influx and efflux on the other; (hence the want of these appearanees in breaking steel, &c.) and void of every other occupant, than this elastic vapour, which is generated im their first formation, which, like secd in the womb, seems to, be the very germ or rudiment of elementary fire, and only waits the invitation of excitation to manifest itself: and whenever this excita- Ya len 33 Experiments on the Eland Granade, &c. tion is begun, how irresistible are the effects producéd by it! I believe nothing in nature (if small things might be compared with great) is more analogous to an earthquake than the bursting of one of these little tears of glass, or more like it in its cause; for both arise from a sudden, combustion of a latent and inflammable principle contained in their interior parts ; and both alike cause a derangement of the parts which heretofore formed their orbicular prisons. To ascertain whether they were charged plus or minus*, I placed them in an insulated situation, on a large flint glass condensing receiver; and with a hammer of the same kin of glass (both being well excited) I broke some of them at the small end: but, contrary to my expectation, the result was the same as if broken in my hand. I next placed some of them on a table, which } knew ta be a good conductor, and with my glass mallet or hammer I broke several more with precisely the same effect. I also broke some with a conducting, 7. e. a common hammer, upon the excited receiver, but there was no diffe. rence in the effect: for all the means I made use of (how~ ever varied) were productive of the same appearances as when broken in my hand, or by the collision of a conduct- ing substance, while they were placed upon another con- ductor. . And now, having varied the experiment by all the means T could devise, except I had tried the air-pump, (which [| could not do, as I had not got an open receiver,) 1 began to doubt whether electricity had any share in this phenome- non or not, and to conclude the’effect must be purely me- chanical (for I would not call it a lusus nature) ; when what compensated al] my trouble, and put the matter: past doubt, was this : I darkened the room entirely, baving previously furnished myself with a clear strong glass receiver to prevent the ac- cident of the pieces flying into my eyes; then directing these organs of vision by the feel, I broke several in this in- closure, where they uniformly produced a bright corrusca- tion like lightning; which, together with the more than mechanical snap they make upon breaking, quite satisfied * To those who are unacquainted with the history of electricity, it may be needful to observe, that the terms plus and minus, + —3 positive and negative; vitreous and resinous; are not six different electrical qualities ; but three sets of equivalent terms, in different systems of the same science, indicative of the two or contrary principles which reciprocally attract each other, and cause what is called the electric shock. ‘There are also other terms by way of designating the same principles, as derrene and atmospheric 5 but these are not so common. me Twenty-third Communication from Dr. Thornton. 339 me that it was not the mere mechanical collision of the air striking the internal surface which so forcibly rends them asunder, but a compound effect of that and electrical affi- nity together; which, being corroborated by so many actual experiments, makes me believe the pheenomenon, of these little philosophical enigmas is nearly expiored. And although I weuld not say the subject is entirely exhausted, yet this solution has so satisfied my mind, that I cannot think it any longer a desideratum. I remain, sir, Toolev-street, Your obliged servant at command, Sept. 14, 1805. ; JoHN SNART. P.S. Since the publication of my paper in the 86th number of the Philesophical Magazine, from a comiparison of the creature therein described with what I have met with in Dr. Shaw’s work, I am inclined to-think it 1s a darva of the genus dytiscus, of the erder coleoptera. It might not improperly be denominated ranamalgus, or frog-sucker. LI. Twenty-third Communication from Dr. THORNTON. To Mr. Tilloch. E Sept. 14, 1805. DEAR SIR, No. I, Hinde-street, Manchester-square, 4 4 Pear me the honour of continuing, in your excellent magazine, facts confirming the propriety of employing pneumatic medicine. Case of Consumption cured by Hydro-axotic Gas. James Davis, et. 25, living with Mr. Chambers, banker, Bond-street, as groom, had all the marked symptoms of 4 confirmed galloping consumption, violent cough, frequent pains in the side, shortness of breathing, the expectoration very copious, of an opaque appearance, night sweats con- stantly, wasted almost to a shadow, and extremely weak, arising from a cold proceeding from putting on a damp shirt, and being wet through, in March 1805. The vio- lence of this disease had existed two months. He was re- commended by Joseph Workman, who had been similarly affected, servant of captain Bond, also cured by the same plan. This patient inhaled the hydro-azotic gas, and he took at the same time tonic medicines, as bark, columbo, with myrrh, with occasional aperients; and, following Y4 this 340 Notices respecting New Books. this plan for six weeks, he was restored to perfect health. The patient is now before me, Sept. 14, 1805; and in excellent health, looks well, is fat, has since had no com- plaint of any kind, and is an additional proof of the virtue of the aérial remedy. I have the honour to remain, Dear sir, &c. Rogert JoHN THORNTON. Oliservations on this Case.—The same opinions arise here as in other cases: but the pneumatic practice is more par- ticularly necessary, as tonics would only augment the malady, if applied alone, as the lungs are locally inflamed ; and- the Jowering plan would only have aided the debility induced from this local cause, exciting an immoderate mor- bid secretion from the lungs. LII. A simple Method of making Tubes of elastic Gum or Caoutchouc, to avoid the Expense of Solution in A&ther. Seurr a stick of cane, and then apply ‘together again the split pieces, but with a slip of whalebone interposed -be- tween them. Cut the elastic gum into slips fit for twist- ing over the prepared cane, so as to cover it; then, by duly heating the surface of the cane covered with the caoutchouc, it will melt so as to form one piece. When cold, draw out the interposed whalebone from between the split cane; by which means, without difficulty, the whole substance of the cane may then be readily withdrawn from under the cover- ing, thus leaving the tube formed as desired. Some recommend-winding small thread round the twisted gum clastic, to help to unite the jomings, and em- ploy the heat of boiling water. aaa SSSSSSSssaa>>>aa&«&«&w{«awa—m=muu=s—'] LIII. Notices respecting New Books. Medical Sketches of ‘the Expedition to Egypt from India. By James M‘Grecor, 4. M. Member of the Royal College of Surgeons of London; Surgeon to the Royal Regiment of Horse Guards ; and lately Superintending Surgeon to the Indian Army in Egypt. 1804. Tue health of soldiers, and particularly when engaged in distant expeditions, is of so much importance, that every publication which can tend to promote so desirable an ob- 1 ject Notices respecling New Books. 341 ject deserves to meet with a favourable reception. This observation, in our opinion, is very applicable to the pre- sent work, as it relates chiefly to a country interesting to Great Britain, under various points of view, and which, in the present situation of public affairs, may again afford British soldiers an opportunity of showing “what they are able to achieve, when commanded by able and experienced officers. These sketches are divided into three parts. The first gives the medical history, or rather the journal, of the expe- dition : in the second, the author, after attempting to as- sign the causes of the discases’ which prevailed, proposes somé modes of prevention: and in the third, some account of the diseases is given. “¢ The first division of the army intended for the expedi- tion to Egypt, under colonel Murray, sailed from Bombay in January, 1801. Theirvoyage was rather a tedious one, and the sinall- pox and a remitient fever broke out among them. They touched for refreshments at Mocha and at Jedda, and on the 16th May, 1801, came to anchor in Kossier-bay ; the prevailing winds in the Red Sea, at this time, rendering itimpossible to get so far up as Suez. «© The second division of troops (originally intended for another time), under colonel Beresford, sailed from Point de Galle, in Ceylon, on the 19th February; and on the 19th May disembarked at Kossier. “* The last division, under colonel Ramsay, sailed from Trincomalée, in Ceylon. They were later of arriving at Kossier, and were not able to cross the desert before July. «© At Kossier there is a fort and a town, if they deserve the name. They are built of mud, and the Arabs inhabit them only at the season when caravans arrive with the pilgrims for Mecca, and with corn for that and the other ports on the opposite Arabian coast.’ Soon after the arrival of the troops at Kossier, they were all attacked with a diarrhoea, occasioned by the water, which contained much sulphate of magnesia. “At first the men were greatly debilitated by it ; bit as they became used to the water, it ceased to affect “their bowels: on the whole, however, it appeared to have produced salutary effects, and the army for some time was uncommonly healthy. On the 19th of July, 1801, the 88th, with two companies of the 80th regiment, under the command of colonel Beres- ford, as the advance of the army, commenced the march across the desert ; but as they had the digging of wells, and other duties to perform, they did not reach the banks of the Nile 342 Notices respecting New Bocks. Nile until the next month. The rest of the army marched on the following days, the marches being always performed by night, andthe armiy, with very inconsiderable loss, reached the banks of the Nile in a very healthy state. The course it pursued was nearly that travelled by Mr. Bruce. During almost the whole of July the army was encamped on the banks of the Nile, which now began to overflow its banks near Ghenné; they, however, soon prepared to move, and detachments went up to Thebes, Luxor, and the cataracts, to press all the boats; and about the end of the month the army began to move to Lower Egypt. The 10th regiment marched to Girgé, the capital of Upper Egypt, sixty miles below Ghenné, and on the 27th and following days the rest of the army was embarked in boats. The thermometer had a wide range at Ghenné ; in the author’s marquee it va- ried from 71° to 108°, on the 20th it rose to 111°, and in the open air the heat was from 70° to 115°. By the 12th of August, the greater part of the army, after a navigation on the Nile of nearly four hundred miles, arrived at Ghiza. As they landed, the troops were uncom- monly healthy ; but in three weeks the sick of the army ex- ceeded one thousand. A considerable number of ophthal- mic cases occurred, but the prevailing disease was fever; in general it was of short duration, of two, three, or five days at most, and rarely proved fatal. In the month of Sep- tember the plague made its appearance in the hospital of the 88th regiment, in the neighbourhood of Rosetta, which rendered it necessary to adopt measures for preventing the further progress of this destructive scourge. Next to the plague, the most formidable disease in the army, from its seneral prevalence, was ophthalmia. Jn the 10th and ssth regiments there were upwards of three hundred and fifty cases, and the total number in the army exceeded six hun- dred. Dysentery and hepatitis, prevailed very generally ‘among all the European corps, and the mortality of the month was very considerable. In the month of January, 1802, the cases of plague in the Indian army amounted to 72, in March the number was 46, and in May 96. On the last day of April, orders arrived from England to general Baird, to return with his army to India, and to de- tach the 10th, 61st, and 88th regiments, which were placed on the British establishment. On the 3d, the Indian army began to march to Ghiza, where it remained encamped by the pyramids for some days, until water and other neces- saries for the passage over the desert were reported to be ready. They crossed the river, encamped at Boulac, i off : rom Notices respecting New Books. 343 Rois Cairo, and, passing the ruins of Heliopolis, made El-Hadje their first staze. Their marches over the desert of Suez, as in crossing the great desert, were all performed during the night, ane they always encamped by sun-rise in the mor rning. -By the end of the month, the whole corps, except the ith Bombay regiment, had crossed the desert, and arrived at Suez. Part of the army was encamped near the town of Suez, and part at Moses Wells, nine miles on the eastern side of the RedSea. The march over the desert of Suez was performed with much greater ease than ‘that over the desert of Thebes. The weather was cool and fa- vourable ; the hot winds were less felt, and they found abundance of good water provided at the Joh stations. On the 2d of June, the embarkation commenced, and by the 15th the whole army was embarked, and had alle’ for the different presidencies, except the 7 th regiment, which, on account of the plague still pal Ne res in it after the rest of the army had embarked, was ordered to remain two months. Most of the corps of the army embarked in the most healthy state. é “* To conclude,” says the author, ‘ never, perhaps, was there an army embarked for any service more healthy than tlre Indian army was when it re-embarked on its retarn trom Egypt. ae Previously to the arrival of Fs army from Egypt, in order to provide against the introduction of the plague into India, quarantincs were established at the presidencies of Bombay, Bengal, and Madras, as well as at the island of © Ceylon. The principal of these was at Butcher’s Island, near Bombay, where there were pest and quarantine phat blishments, of which, on my arrival in June, I took the charge. Atthis period, letters from Dr. Short, at Bagdad, and from Mr. Milne, at Bassorah, described the plague as raging in Persia, and particularly at Ispahan and Bagdad : in consequence of this information, every vessel, both ino the Red Sea and Persian Gulf, was ordered a Butcher’s Island. «<< As the ships arrived, the troops from the Red Sea were landed ; but the artillery, 86th regiment, Ist Bombay regi- ment, and the commissariat department, were so uncom- monly healthy, that I detained them but a very few days on the island. «© The 7th Bombay regiment Ianded at Butcher’s Island in August. As this was the corps in which the plague had principally prevailed, though they were not unhealthy, I judged it prudent to detain them a month. On nny last inspection 544 Notices respecting New Books. ( imspection of them before they left the island, of a total of seven hundred, including sepoys, their wives, and the public and private followers of the corps, | found only four. sick, and these I believe were all catarrhs. ’ ss (Drs Henderson, with the pest-establishment, and. all those whom we had left at Suez, arrived at Butchcr’s Island on the Ist September. The convalescents from the plague, as well as the guard, and the pest-house servants, w ere, on their arrival, all of dian very healthy : but I thought it safe to keep them in quarantine on the island till October; when, like all the others who had beem in quarantine, they were provided with new clothing and sent over to Bombay. ‘¢ The company’s packets front Bassorah, and the vessels which arrived from the Persian Gulf, had none ef them the Jeast suspicious appearance, and I found that their crews were all very healthy. s¢ } had likewise the satisfaction to receive accounts from the medical gentlemen employed in the expedition, after their arrival at Calcutta, Madras, and Ceylon: their ac- counts were so late as November. In none of the corps did any death occur from the time of embarkation at Suez.” fn part second, the author gives some obserxvations on the climate of Egypt, as connected with the diseases which pre- vail in that country. ** The cultivated part of Eevpt, particularly the Delta, is a very rich country ; in fer tility and luxuriance of soil yield- img to none under the face of heaven. Theart of husbandry is there but i imperfectly known ; and at their harvests there #s a very great destruction of vegetable matter, from which hydrogene gas, or hydro- carbonate, 1s extricated in great quantities. Under similar circumstances, in America as well as in India, J have seen a bad fever of the intermittent orremnttent type appear. But in Egypt after the subsiding of the Nile, which in many places had covered a great ex- tent of country, there is a great exhalation from the mud, and from the putrid animal and ve eoetable matters left be- hind. The effluvia of these substances, acting on the human body, will readily account for much disease. If we add to these the extreme filth of the inhabitants of Egypt, their poor dict, their narrow, close, and ill-ventilated apartments, gener ally meh crowded, with the extrente narrowness of their streets, and the bad police of their towns, we shall not be astonished if a fever, at first intermittent or rcmittent, should have symptoms denominated malignant, superadded to the more ordinary symptoms of the disease. If an imported conta- gion should make its appearance. at the same time, and under Notices respecting New Beoks. ‘345 under the above circumstances, we expect a most terrible disease. “ The dry parching wind, which comes over the desert, aad which at certain seasons blows in Egypt and in Arabia, is well known, 2nd was often severely felt by the army on their march, both across the desert and the isthmus of Suez. The whirlwinds of sand roll with great. impetuosity, are very troublesome, and insinuate fine sand and dust every where. [tis hardly possible to keep the minute particles out of the eyes. “ The dews, which fall in Egypt, I always heard were very heavy, and were a cause of the diseases of the country. T had occasion too, more than once, to hear the natives at- tribute much to them as the cause-of their diseases; with what justice T will not ete to decide. From some ex- periments which I made in India, on the Red Sea, and lastly in Eeypt, I am inclined to think that they are equally heavy in the two former as in the latter quarter. After weighing the matter carefully, [ took a quantity of lmt, twelve inches square, exposed it for a night to the dew, and, by weighing it in the morning again, ascertained the quantity which a had gained. [ am aware that this is by no means anice ex- periment, and that in the performance of it several particn- lars demand attention ; but it is sufficient to our purpose, and I learned by it, that, j in the island of Bombay, on the Red Sca, and in Lower Egypt, the quantity of dew which falls is nearly equal. j “‘ It ought to be mentioned, that, durimg the year we were In Egypt, the season was not the usual one. There was a greater overflow of the Nile. It rose higher on the Nilometer than it had done for-several former years, and it was remarked to be much later in subsiding at Rosetta. “< The fall of rain at Alexandria was greater than on for- mer years; and, at Rosetta, the rains were in setting-in later than usual. The season of the plague set-in much earlier than usual*. “© In general, the Thebaid, or Upper Egypt, is healthier than the Lower. Never were troops more healthy than the army when enc amped near Ghenné. «* Ghiza, the antient Memphis, at the time the army disembarked there from Upper Eeypt, we found to bea very unhealthy quarter. |For a considerable time, aed im- mediately before the arrival of the Indian army, it had been * These circumstances I learned from a member of the French Institute, and from the Pharmacien en Chef to the French army, who often related to mc the order which Bonaparte gave him to pgison the wounded with opium the 346 Notices respecting New Books. the station of large armies: alternately of Turks, Mamelukes, French, and English. From ali these armies a number died at Ghiza, and there was much filth and noxious effluvia. We saw there enough of putrid animal matter to generate contagion. Whether this was or was not the cause of the fever which prevailed, 1 will not attempt to decide. One circumstance may be mentioned : we were here joined by a detachment of the 86th regiment under colonel Lloyd, which, for some months before, had been doing duty with the vizier’s army, which never was healthy. ‘That the cir- cumstances which existed at the time of cur occupying Ghiza were the cause of the fever, is manifest from this, that, subsequently to the army going to the coast, the garrison left-in it found Ghiza a most healthy quarter. The same objections are to be made to Rhoda that are applicable to any marshy situation.” In the third part of this work, which gives an account of the discases of Egypt, Mr. Macgregor has brought forward some new facts in regard to the plague, and parucularly the treatment, which are well worth the attention of medical men in general, and of those in particular who may visit countries where this disease is prevalent. It is commonly believed, that the proyress of this contagion is stopped by ex~ tremes of both heat and cold: but if this be true in regard to heat, it did not appear to be so in the army of Egypt im re- gard to cold; forthe period at which the plague raged most was in the coldest months. In regard to the treatment, nitric acid was given internally,and where the patients would drink it it showed good effects. Bark, wine, and opium, were largely administered, and at a certain stage the cold bath, for the purpose of obviating that debility which always appeared to be very great. At first, calomel was used only as a purgative, but at last the use of this remedy was carried farther. «On the whole,” says the author, “in mercury and the nitric acid we appear to have excellent remedies for the plague; but they must be very early and very hberally ex- hibited. Ifthe first stage is allowed to pass over before they are given, the scasun of doing it with advantage is in danger of being lost.” In regard to preventive means, the following observation seems so -well calculated to remove that despondency which generally prevails when the plague exercises its ravages, that we cannot help quoting it. « There was hardly a corps in the army,”’ says the author, © where, at one period or other, the disease did not make its appearance ; but it was always in our power to arrest its pro- gress, In well regulated corps, where a rigid discipline was 8 enforced, Noétlces respecting New Books. 347 enforced, and proper attention to the interior economy was _ paid, it rarely happened, indeed, that much difficulty was ex- perienced in eradicating the contagion. As our success in the prevention,” adds he, ‘ was so great, all that remains for me is to mention the substance of general Baird’s order to the army on the subject. © 1st, To every hospital, an observation-room, or in lien of it a tent was attached ; and to it every case whatever with febrile symptoms was sent, as soon as discovered, and was there most strictly watched by the surgeon. “ odly, On any symptoms of the plague appearing, the ease was instantly sent to the pest-house from the observa- tion-room of the regimental hospital: the patient was ac- companied by the medical gentlemen of this corps whe attended him, and who gave the medical gentlemen at the pest-house an account of the previous treatment of the ease. «¢ Tf any doubt remained, the patient in the first instance was placed in the observation-room of the pest-house ; and, if the disease did not turn out to be plague, he was sent to the quarantine. “ 3dly, In every corps, and in every department, a minute mspection by the surgeon was made twice a week ; and every person with the smallest appearance of ill-héalth was sent to the hospital. “ 4thly, Every corps or hospital, where a case of plague had appeared, was put into a state of quarantine; and, in such corps or hospital, an inspection by the surgeons was made at least two or three times a day; and every case with suspicious symptoms was ordered to the observation-roctu. “ 5thly, In suspected corps it was ordered, that, under the inspection of a commissioned officer, every person should be bathed more frequently, and at stated periods; and, likewise, that all their clothing and bedding should be frequently washed and baked. To all the hospitals, ovens and smoking-rooms were attached. 6thly, Quarters of corps, hospitals, and ground of en- campments, were frequently changed. * 7thly, Much is to be attributed to the nitrous fumiga- tion. In several instances it was attended with the best effects. The lamps, with this, were kept constantlyybura- ing in the observation-rooms, and in the rooms from which the cases of the plague had come. Vessels, with the ma- terials for the fumigation, were likewise placed under the beds, and in the corners of the rooms. When our stock of nitre was at length exhausted, we substituted marine salt tor 348 Notices respecting New Books. for it; but this fumigation could not be kept up in rooms. where the patients were all confined to their beds.” The next malady which engages the author’s attention is the ophthalmia, which in Eoypt at particular seasons 18 a most generally-prevailing disease. li is not, however, con- fined to the human race; the animals of the country, parti- cularly the dogs and Be are subject to its attacks. In Egypt it proved most distressing and obstinate. The French, it was said, sent from Egypt to France 1000 blind men. The number sent home from the English army was very considerable likewise. Of the Indian army 50 were sent home invalids from blindness; most of whom were from the loth and ssth regiments. “< The disease, I think,” says the author, ‘* might gene- rally be resolved into, Ist, either of Cullen’s two species, the ophthalmia tarsi and the ophthalmia memibranarum 5 edly, to a combination of these two; or, 3dly, to a species of ophthalmia, frequent in India, sy mptomatic of disease in the biliary secretion. ** The appearance which the disease put on, particularly the two first species of it, was nearly what we have seen in other parts of the world; except that the symptoms ad- vanced with alarming rapidity to the highest inflammatory stages. In most cases the attack was sudden, and very ge- nerally at night.. Speedily, the patient complained of a (=) burning heat of the eye-ball, or of a sensation of needles being passed through the eye. There was a considerable swelling of the ball of the eye, of the eye-lids, and some- tinies of the neighbouring parts. Almost always, there was a copious flow of tears, which felt hot and scalding, and, as they flowed, excoriated the face down. Very frequently : there was a ‘racking head-ach and general fever. Gidema of the eye-lids was irequenbly met with in the early stage of the disease, and inversion of the cilia in the last stages. 204 America, South. Travels in, 54 American Indians of Asiatic ori- gin, 209 Analysis of a mineral from Der- byshire, 35; of milk, 176; of smut of wheat, 177; of guano, 1773 of opium, 178; of cerite, 193 Animal life. Patent for sustain- ing, 369 Animal substances. Experiments on, 173 Antiquities, 188, 363 Antoni on velocity of musket balls, 228 Ants. On, 49 Aprera. On the, 50 Aquatic animal, New, 135 Arcy (a’) on velocity of projec- tiles, 227 Artillery. On, 1220 Arts, fine. Academy of, go Arts, fine. A prize question, 92 Astronomy, 93, 199, 353, 360, 6 3 Atmosphere free from hydrogen, 174 Axletrees. Patent for, 95 Barber's patent, 287 Barometer. On the, 357 Larton (Dr.) to M. Lacepede, 2 3% Barytes, On, 218 Batey’s patent, 369 Bergman’s projected journey, 188 Berzelius’s discovery of cerite, 193 Bevan’s patent, I9t Biot on formation of water by compression, 173; on mag- netism, 248, a Birds. On, Biography. Life of Priestley 166 Blight of wheat. On, 68 Blunt’s patent, 1gT Bolschoi's (Dr.) i aps and ransom, 186 Boaz’s patent, 369 Bonpland’s travels, 54 Bossut on velocity of projectiles, 220 Books. New, 171, 284, 340 Botany, go Bramabh's patent, Bread made of the flowering rush, Bridles. Patent for, ° British Institution. The, &s Brodie’s patent, \I9L Brunel's patent, 190 Burton's (Dr.) case of hydro- phobia, 257 Caldwell’s patent, 370 Combustion. Patent for maintain- ing, 369 Candlesticks. Patent, 369 Cannon balls, Velocity of, 220 Caoutchouc. Tubes made of, 340 Carey’s meteorological table, 96, 192, 288, 371 Carriages. INDEX. Carriages, Patent for wheel, 190, IgI Cattle. On feeding, 212 Ceres. Tables of, 93, 199, 367 Cerite. Discovery and analyses of, 193 Cerium. A new metal, 174, 193 Chapman's patent, 370 Charcoal converted into tannin, 27t Chaumeton on medical entomo- logy, 49 Chenevix on platina and mer- cury, 26, 103 Cinnabar. Preparation of, 123 3 native, found in Virginia, 210 Clouds. On stones from the, 71! Cobalt. New metal found in, 93 Collins’s patent, 287 Colours. On, 289 Consumption cured by hydro- azotic gas, 25 Consumption. Cure for, 339 Copper found in America, 210 Corn. Patent for reaping, 287 Cowan's patent, 287 Coypou. On the, 330 Crale. On the, 51 Currying of leather. On, — 273 Davy. Analyses by, 35 Deaths, 94 Deluc on volcanoes, 262 Deverell’s patent, 370 Dickinson’s patent, 369 Diseases cured, 255257 Doda’s patent, 95 Dying. Pateut for, 370 Earth. On the theory of the, 155, 200 Earthquake at Naples, 364 Edwards's patent, 190, 191 Elasticity. Tilloch on, 138 Elliot's patent, Igo Entomolog 1, medical, 49; Ame- rican, 206 Evans’s (Dr.) description of Sutton Spa, 61 Farms. On size of, 217 373 Filtration of water. Patent, 369 Fire-arms. Patent, 369 Fire-places. Patent for improv- ing, 95 Flushing. Society of Sciences at, go Flowering rush makes good ' bread, 284 Fontana. Death of, 94 Formica. On the, Fourcroy’s analysis of milk, 1763 of smut of wheat, 1773 of guano, 177 Frinch National Institute, 1729 274 354 Galvanism. Muriate of potash produced by, 153, and muri- atic acid, 1793 speedy de~- composition of water by, 260 Geoffroi on mammalia, 328 Geography, 358 Giesecke’s projected journey, 188 Glass. On polishing, 112 Glass-svorking. Patent for, 37° Glue. On, 274 Goeiling on barytes, 218 Grapes. Sugar made from, 177 Grobert’s way of measuring ve~ locity of projectiles, 220 Guinea worm. On, 350 Harp. Parent for tuning, 95 Hatchet on artificial tannin, 271 Heights. Bavometric measures ment of, 346 Henry on the radical of muriatic acid, 183 Herman’s projected journey, 188 Hisenger’s discovery of cerite, 193 Hobson’s patent, 95> 19t Horrock’s patent, 191 Humbold?’s travels, 54 Humboldt on magnetism, 248 Hurricane. Accountofa, — Ig Hutton (Dr.) on stones from the clouds, 71 Huston on velocity of projectiles, 22 Hydromis. 374 INDEX. Hydromis. On the, 331 ydrophobia cured, 257 Zndigo treated with nitric acid, 173 Institution. Formation of the London, > 855 Institution, British, Formation of, 88 dastitutions, New, in America, 89 Iridium, A new metal, 273 from abundant in North Ame- rica, 210 Sapan. Expedition to, 1, 115 Feferson (President). On the, Jesty the inoculator, ae Fubb’s patent, 95 Jobnson’s patent, 370 Fones on the coming-up gfass, 319 Kay’s patent, 370 Kent’s patent, 369 Knight on sap of trees, 309 Koeler on plants, 231 Krusastern’s (Von) expedition to Japan, I, 113 Languages of the American tribes, 209 Lava. On, 262 Lead found in America,* 210 Learned Societies, 85,172, 271, 353 Lectures, 285, 369 Life-bucy. Patent, 19! Locks. Patent for, 1gt London Institution. Formation of, 85 Loom. Patent, 191, 370 Lumincus rays. On, 28g M‘Gregor’s Medical Sketches, 340 Magnetism. Variations of, 248, 299 Mammalia. New genus of, 328 Manus-ripts. Antient, 363 Marquesa islands. The new, 6 Marshal on blight of wheat, 68 Marsland’s patent, 370 Mathematics, 355 Mathey’s machine for measuring velocity of musket balls, 228 Maudslay’s patent, 1 3979 Medical and Chirurgical Society. Institution of, 279 Medical entomology. On, 49 Medicine, 355; 25, 63, 257% 339 Metals. New,~ 174 Mercury, Action of, on platina, 26, 1033 oxides of, to pre- pare, 1335 132 Metecrology, 96, 192, 288, 371 Mitals. New, 93; 193,273 Mildew of wheat, On, 68 Milk analysed, 176 Miller's patent, 191 Minerals, American, 210 Mirrors. Ou the manufacturing of, Liz Mitchill (Dr.) on American winds,: 14 Monge on velocity of projectiles, 220 Moral Sciences. A prize ques- tion, 35 Mountains. On declivities of, Muriate of barytes. To prepare, 218 Muriate of potash produced by galvanism, 153 Muriate of soda excreted from the human skin, 184 Muriatic acid. On the elements of, 152,179, 183 Mushet on wootz, 4° Musical instruments, Patent for tuning, 95 Musket balls. Velocity of, 223 Natural history. A prize ques- tion,’ gt Natural history of North re eica, 97, 204 New Holland. Facts: respecting, 357, 200 Noble’s patent, 369 INDEX. Nicke?, New metal found in, 93 Nicolan. A new metal, 93 Ogier’s patent, Igt Oniscus. Gn the, 53 Optithalmia. Oa, 349 Opium analysed, 178 Oraithology, 204 Oviparous quadrupeds, 205 Pacchioni on radical of muriatic acid, 179 Pesium, ‘ainibsai city of, 363 Pantiles. Patent, 370 Pallas. Dsceneian and declina- tion of, 939 190, 367 Palladium for sale, 190 Paper. Patent for, OR Parnseutier on oxides of mercu- ry, 123, 132 Parke’s travels, 287 Parrots. Ov, 204 Patents. List of, 95, 190, pith 359 Peel on production of muriates from water by Galvanism, 153 Perim on the theory of the earth, 155, 200 Pidgesn’s patent, 191 Plague. On treatment of, 340 Plants. Physiology of, 231, 321 Platina, Action of, on mercury, 26, 1035 experiments on, 273 Plough. Jeflerson on the, 79 Pluckneit’s patent, 287 Pneumatic medicine, 25, 339 Poetry. A prize question, 353 Pompeii. Further discoveries at, 188 Potash produced by Galvanism, 193 Powys's agricultural remarks, é 212 Priestley. Life of, 166 Prieur on colours, 289 Printing. Patent, 370 Prismatic colours. On, 289 Prize cuestions, 91, 93,353 Projectiles, Measuring velocity of, 220 375 Prussta. Prize question by king of,” 93 Publications. New, 171, 284 Ramsaen’s coming-up glass, 319 Rattlesnakes. On, 206 Rhodium. Anew metal, 273 Rodins’s method of determining the velocity of musket bails, 227 Rowutree’s patent, 98 Royal Secict}. London, 2715353 Rumford on producing heat by colar rays, 1725 on velocity of projectiles, 227 Rupert's drops. On, 334 Russian embassy to Japan, 1, 1153 to China, 187 Saddle, Patent, . Igt Sage on polishing and silvering mirrors, 112 Saturn. Form of, 353 Sawing mills. Patent for, 190 Scieaces and fine arts, A prize question, co Scorpion. On the, 50 S:ott's patent, 370 Seguin’s analyses of opium, 178 Seguin on glue, 294. Seeizen’s travels, 287 Seppings’s method of suspending ships, 242 Sheathing of ships. Patent for, Qt Ships. To suspend, 242, Ship’s sails, Patent, 28 Silex. Origin of, in vegetables, 176 Silvering of mirrors. On, 112 Si/ater’s patent, 190 Smut of wheat analysed, 177 Snart on a nondescript aquatic animal, 135 on Rupert’s drops, 334 Societies, Learned, 85, 172,271, 353 Solar rays. Force fof, in pro- ducing heat, 172 Steam. Patent fer generating, ° 191 § (edie 376 Steam-engine boilers. Patent, 19% Steam-engine. Patent for, 369, 37° Stevens’s patent, ig Stirrups. Patent for, 19t ‘Stockings. Patent, 287, 370 Stone in the bludder. On, 51 Stones from the clouds. On, 71 Storms. On allaying, by means of oil, gl Sugar made from beet-root and grapes, 177 Sugars. Patent for refining, 369 Sulphate of barytes. "To decom- pose, 218 Sutton Spa. Account of, 61 Swallows. Torpidity of, 204 Tannin. To produce,by art, 271 Fanning. Patent respecting, 370 Telescope. A new, 319 J ennant’s discovery of iridium, 273 Teylerian Society, Haerlem, 353 Thornton (Dr.) on pneumatic medicine, 255339 Tilloch on elasticity, 1383; on production of muriates by Galvanism, 152 Timber. Observations on, 309 Tinfoil. Manufacture of, 113 Travels, 54, 186, 187, 283 "B89 INDE xX. Vaccination, 189, 279 3275 3073 Van Diemen’s Land. Ony 157> 200 Fauquelin's analysis of milk, +763 of smut of wheat, 177; of guano, 1773; of cerite, 1093 Ventilator. Patent, 287 Fiolin. Patent for tuning, 95 Volcanoes. On, 262 Voyage to Kamtschatka, 4, 115 Water produced from its ele- ments by pressure, 173 Water-gladiolemakes goodbread, 284 Wilkinson’s patent, 370 Wilson on Galvanism, 260 Wilson’s patent, 369 Window-frame. Patent, | 19k Winds. Mitchill on, 14 Witherby’s patent, 369 Wolaston’s discovery of palla- dium, 272 Wood-louse. On the, 53 Woolf’s patent, 369 Wooll-combing. Patent, '369 Wootz. Experiments on, 40 Yellow fever. A prize question, 93 Zink. Patent for manufacturing, 95 ee a a BoA iy END OF THE TWENTY-SECOND VOLUME. —_— Printed Ly R. Taylor and Co., $8, Shoe Lane, Fleet Streéte Philo. Mag. PULVou. XXM Pug .3. oY ey bea | ‘ } Te 7 —— ee Mag Pl.If Vol. XXII. iV ‘ Gh 57 Philo. Mag . Vol. XXI. PUI. Buds and ramifications of Plants. A tg. 2/4 as Scale % of Philo. Mag. Vol XY PL IV. Inch to a Foot. i, Bee : ie Philo. Mag Vol. XX. Plate V. Philo. Mag . Vol. XXIT, PL. VT. Hydromis Coypou : aly Philo. Mag Vol. XXM. PLVIL. —~ —— a ale Mint AN A. Red bellied Hydromys . PL. VAL. Philo. Mag. Vol... _D. ws lower Jaw. @ of the same An Oars fe97 do Hydrom 4 B. White belli jit ie “- Sh LU CB 1 Ss olagky ied faa AN