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and defroy the poppy; and it is therefore as evident, that it is utterly impoffible, trom the nature of the two plants, that one hould be plowed up to fow the other.'

The author proceeds to give a diftin&t account of the Indian government, both under the ufurpation of the Mahomedan conquerors, and the lenient rule of Great Britain. It is impoffible for us, at prefent, to follow him through the minuteneft of the detail, but we have the pleasure to obferve, that he conducts the narrative with the greatest appearance, not only of knowledge, but fidelity; and that, according to the clear and confiftent reprefentation he has given, the happieft effects have refulted to the inhabitants of India, fince they came under the mild and prudent administration of this country.

Philofophical Tranfa&tions of the Royal Society of London. Vol. LXXIX. for the Year 1789. Part II. 410. 75. 6d. fewed. L. Davis.

THE

HE firft article in this fecond part of the Transactions was communicated by Dr. Priestley, who tells us, that it is the beginning of his enquiries on the doctrine of phlogiston, with which thefe experiments on the phlogiftication of fpirit of nitre' has fome connection. It has been doubted whether heat or light is the cause of thofe orange-coloured fumes, which arife from pale spirit of nitre after being expofed to the fire; but Dr. Priestley has shown that it is heat, though he has not proved that light will not have the fame effects. We lately mentioned, that the fmoaking spirit of nitre has been changed into the colourlefs fpirit by excluding the light for fome years; and, as it was kept in a close cupboard, very near which there was a conftant fire, during the winter-months, the alteration of heat could not be confiderable. Independent of this caufe, fpirit of wine, inclosed in a small tube, and fuffered to fall gradually into the pale nitrous acid, produces the oppofite effect: each experiment proves that phlogiston, which is certainly connected with both heat and light, has fome fhare in the change. It appeared, however, from Dr. Priestley's particular experiments, that the vapour over the fpirit was first changed, and the liquor only altered in confequence of it; but this must be accounted for from the heat or light more immediately affecting the air, as more near to its own ftate, than a fluid; fince in our experiment the fpirit of wine first changed the acid. Again, our author found that fome dephlogisticated air was let loose during the change, and fome phlogisticated air abforbed; though in very different proportions. The latter was only that contained in the atmof

pheric air neceffarily refting, after every precaution had been taken to exclude it, on the acid; and the former appeared to be a real production, either from the decompofition of the acid, or fome other caufe. We own that this fact, notwithstanding Dr. Priestley's explanation, feems to bear hard against the doc trine of phlogiston. The dephlogifticated air formed rushes out turbid and white; but this is the conftant appearance of condenfed or rapidly formed air, as is feen in the difcharge of the wind-gun, or other common experiments. Dr. Prieftley afterwards answers fome objections, which have been made to his former paper on the decompofition of water.

Art. XXIII. Experiments on the Tranfmiffion of the Va. pour of Acids through an hot earthen Tube, and further Obfervations relating to Phlogifton. By the Rev. Jofeph Priestley, LL. D. F. R. S.-We turn to the end of the volume, to connect this paper with the former, as their fubjects are so nearly fimilar. Dr. Priestley tells us, that, in his fubfequént experiments, he has confirmed thofe in the former communication, and extended them. He finds fimilar effects from heat in phlogifticating the vitriolic acid, which he thinks in this and the former inftance fhould be ftyled fuper-phlogiftication, as in their colourless state the phlogiston appears to be in its proper proportion. The vitriolic acid, however, gives out air work than common air; and, as he had formerly found vitriolic acid air injure common air, he fuppofed it might be owing to this cause when he previously feparated the acid air, that which followed it was of the purest kind. The fame refult occurred in fubjecting spirit of nitre to the fame experiment in each instance there was an escape of acid vapour, and Dr. Priestley feems inclined to explain the refult, by fuppofing that, in both cafes, the acids were faturated with phlogiston, but, on the efcape of the acid vapour, this principle was predominant. The acid liquor collected, when distilled, afforded no air, though that, from the spirit of nitre, towards the end of the experiment, gave out a little; but from other experiments, Dr. Priestley thinks that the vitriolic acid contains the proper element of pure air, particularly as its vapour, with inflammable, forms fixed air. The marine acid was not changed by these procefies. Distilled vinegar, in this way, afforded air, twothirds of which was fixed, and the rest inflammable, Alkaline air is converted into inflammable air by this procefs, as well as by the electrical fpark, but by no means in fo great a degree.

Dr. Priestley next purfues the fubject of phlogiston, and shows that the fixed air found after calcining iron in dephlogifticated air cannot come from the plumbago of the iron, and that therefore the iron must have parted with one principle, as well as

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have received another. In the experiment with Profan blue alfo, Dr. Priestley thinks it unaccountable that so much dephlogisticated air fhould disappear, unless that it contributed, with the phlogifton of the calx, to the production of fixed air. The Pruffian blue he confiders as a phlogisticated calx, and only fo far an acid, as it contains fome fixed air already formed.

Art. XII. Obfervations on a Comet. In a Letter from William Herschel, LL. D. F. R. S. to Sir Jofeph Banks, Bart. P. R. S.-The most remarkable circumftance attending this comet was, that it had no nucleus; but this is not a fingular appearance, though not a common one.

Art. XIII. Indications of Spring, by Robert Marsham, Efq. F. R. S. of Stratton, in Norfolk, Latitude 52° 45'Thefe different appearances of various indications of spring, from that of 1736, a remarkably early one, to the year 1789, cannot be abridged: they are contained in three tables, and the difference is obvious from inspection only.

Art. XIV. An Account of a Monter of the human Species, in two Letters; one from Baron Reichel to Sir Jofeph Banks, Bart. and the other from Mr. James Anderson to Baron Reichel. Communicated by Sir Jofeph Banks, Bart. P. R. S.This is the most fingular monster that we ever remember to have heard or read of. Peruntaloo is now thirteen years of age, born at Popelpahdoo, seventy miles weft of Mafulipatnam; and measures four feet fix inches and a half in height. To the cartilago enfiformis of this boy is affixed the lower extremities of a child, with the pelvis connected to the cartilage by the fym phyfis of the pubis. The legs and thighs of this adventitious child appear extenuated; the anus is imperforated, but the urine is voided naturally, at the will of his more perfect brother; and the penis is occafionally erected. About the lower part of the loins of the femi-monster are two bladders, into which Peruntaloo can occafionally force air, and they have evidently a communication with his lungs. The fac of the ftomach is common to both, but the alimentary canal, for the reafon affigned, is evidently peculiar to the more perfect boy. The legs and fect of the femi-monfter are colder than the reft, and the volition of Peruntaloo feems not to extend to them. We cannot, at this time engage in a difcuffion on the fubject, or fhow the oppofition of this fact to the moft generally received fyftems. We own, that it decidedly oppofes the opinions on this fubject that we have had occafion to give; and we must allow that there are either monftrous germs, or that nerves will unite fo as to admit of conveying fenfation, and even voluntary motion: the former opinion is moft tenable.

Art. XV. A fupplementary Letter on the Identity of the Species

Species of the Dog, Wolf, and Jackal; from John Hunter, F. R. S. addreffed to Sir Jofeph Banks, Bart. P. R. S. Mr. Hunter now informs us that the bitch, produced by the wolf and the dog, produced puppies from a connection with a dog. The time of geftation was the ufual one of the canine race. We hope this ferocious family will not be conti.

nued.

Art. XVI. Abstract of a Register of the Barometer, Thermometer, and Rain, at Lyndon in Rutland; by Thomas Barker, Efq. Alfo of the Rain in Hampshire and Surrey. Communicated by Thomas White, Efq. F. R. S.-The mean heat of April was 5c nearly: the least quantity of rain, recorded in this register, is what fell at Fyfield in Hampshire, 16.86, at leaft two inches more than fell in London from the Society's regifter.

Art. XVII. On the Method of correfponding Values, &c. By Edward Waring, M. D. F. R. S. and Lucasian Profeffor of Mathematics at Cambridge.

Art. XVIII. On the Refolution of attractive Powers. By Edward Waring, M. D. F. R. S. and Lucasian Profeffor of Mathematics at Cambridge.-Thefe memoirs are wholly incapable of abridgement.

Art. XIX. Experiments on the Congelation of Quicksilver in England. By Mr. Richard Walker; in a Letter to Henry Cavendish, Efq. F. R. S. - Mr. Walker was probably the firft who has fucceeded in freezing quick filver in England; and he has obtained, by various experiments, so great a power of producing cold, that he can congeal this fluid metal in the hottest feafon, without the affiftance of fnow or ice. The defcription of the frozen mercury, by Dr. Thomson, we fhall transcribe:

When the freezing mixture was fuppofed to have produced its effect, the bulb which was completely filled was taken out, and broken on a flat ftone by a modera e stroke or two with an iron hammer. This bulb was eleven or twelve lines in diameter.

The folid mercury was feparated into several sharp and brilliant fragments, fome of which bore handling for a short time before they returned to a fluid form. One mafs, larger than the reft, confifting of nearly one-third of the whole ball, afforded the beautiful appearance of flat plares coverging towards a center. Each of thefe plates was about a line in breadth at the external furface of the ball, becoming narrower as it fhot inwards. These facets lay in very different planes, as is common in the fracture of any crystallized ball, whether of a brittle metal or of the earths, as in balls of calcareous stalactite. The folid brittle mercury in the prfent intance bore a very exact refemblance, both in colour and plated structure, to fulphurated antimony, and efpecially to the radiated fpecimens from Auvergne, before they are at all tarnished.

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Infiead of a folid center to this ball, it feemed as if there had been a central cavity, of about two lines in diameter, a contderable portion of which was evident in the fragment just defcribed, at that part to which the radii converged. It is indeed pollible, that this may have been merely the receptacle of fome part of the mercury rema ning fluid at the center. The hollow within was thining, but its edges were neither foft nog mouldering; on the contrary, they were fharp and well defined: nor was the brilliancy of the radii attributable to any exudation of mercury as from an amalgam.

In the two fmalier bulbs, which were only half filled, the mercury preferved its ufual lufire on the furface in contact with the glafs, as well as on that furface which it had acquired in becoming folid. The latter was occupied by a conical depreffion, the gradations of which were marked by concentric lines.

One of theic hemispheres was ftruck with a hammer, as in the former instance, but was rather flattened and crushed than broken. The other, on being divided with a fharp chiffel, thewed a metallic fplendour on its cut furface, but not equalling the polifh of a globule of fluid mercury."

Fragments of folid mercury, thrown into liquid mercury, funk, with confiderable celerity.

Phofphorated natron produces more cold than vitriolated natron; but this, like the other neutrals, lofes this property, if deprived of the water of cryftallization. The mercury on congelation did not fall fo low as in the Siberian experiment; and this was found owing to the formation of an external shell of folid mercury by the fudden application of cold.

By atrial made with great accuracy, I find, that even the mixture compofed of diluted vitriolic acid and vitriolated na'tron is adequate to any ufeiul purpose that may be required in -the hottest country; for, by adding eleven parts of the falt in fine powder to eight parts of the vitriolic acid diluted with an equal weight of water, the thermometer funk from 80°, the mean temperature of the hotteft climate, and to which thefe materials were purpofely heated before mixing, to rather below 20°.

Vitriolated natron, added to the marine acid undiluted, produces very nearly as great a degree of cold as when mixed with the diluted nitrous acid. At the temperature of 50°, two parts of the acid, require three parts of the falt in fine powder, which will fink the thermometer to o°; and if three parts of a mixed powder, containing equal parts of muriated ammonia and nitrated kali, be added afterwards, the cold of the mixture will be increased a few degrees more.

The frigorific mixture above defcribed, compofed of phofphorated natron and nitrated ammonia diffolved in the diluted nitrous acid, being the most powerful, it will probably be found most convenient for feezing mercury, when fnow is not to be procured. The materials for this purpose may be

previously

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