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heat. With the latter, it formis crystals much resembling a filver coloured glimmer, just as common lead would have done ; and it forms regular crystals with the nitrous acid.
The spathose iron ores powdered, and put on a red hot iron, instantly become black; and look like a black, shining, micaceous iron ore.
Zeolite is lighter than the calcareous spars. Treated with an alcali, as in the process for obtaining the liquor filicum, it afforded no neutral salt. The powder edulcorated, and treated with acids, formed the same kind of gelatinous matter, as when the zeolite is employed in its crude state*. Article 4. Account of a Petrifattion found on the coast of East
Lothian. By Edward King, Esq; F.R.S. This petrifaction contained a piece of rope, which had be. longed to the Fox man of war, stranded on the coast of Scotland in 1745, where it had lain under water thirty-three years. This rope was adjoining, and probably had been tied, to an iren ring. The substance of the rope was little altered; but the fand inclosing it was so concreted, as to have become as hard as a piece of rock, and now retains very perfedly impressions of parts of the iron ring, resembling those of extraneous foffil bodies, that are often found in various kinds of strata.
From the circumstances attending this appearance, as well as from other obfervations, Mr. King draws two conclufions : first, that there is, on the coasts of this island, a continual progressive induration of masses of sand and other matter at the bottom of the ocean; somewhat in the same manner as there is at the bottom of the Adriatic fea, according to the account given by Dr. Donati:'—and secondly, that`iron, and the solutions of iron, contribute very much to haften and promote the progress of the concretion and induration of stone, &c.'
In confirmation of the last conclusion, Mr. King produces Come obiervations and experiments made by Dr. Fothergill; which tend to prove, that iron and solutions of iron give an extraordinary degree of hardness to stones washed with them, Before the lign-irons were taken down in the city of London, the Doctor observed, that' on the broad stone pavements, whenever he came just under any fign-irons, his cane gave a different sound, and occafioned a different kind of resistance to the hand, from what it did elsewhere.'-He afterwards found, that every where under the drip of these irons, the stones had
Though there is a table of errata subjoined to this volume, the two following gross errors of the press, as we conceive them to be, are not noticed in it. Page 18, near the bottom, cawk is spoken of as being.“ werred with antimony;' we should furely read treated, or biared with antimony. At p. 30, a subftance is faid to melt' with a moderate degree of tizi' we should read, a moderate degree of heat,
acquired acquired a greater degree of folidity, and a wonderful hardness, so as to refilt any ordinary tool, and gave, when ftruck upon, a metallic sound : and this fact, by repeated observations, he was at length most thoroughly convinced of.'
He afterwards placed two pieces of Portland stone in the fame aspect and situation in every respect; but washed the one frequently with water impregnated with rusty iron, and left the other untouched. In a few years, he found that the former had acquired a very sensible degree of the hardness above defcribed, and, on being struck gave the metallic found; whilft the other remained in its original state, and subject to the decays occafioned by the changes of the weather, which we find in many instances make a most rapid progress.
Mr. King proposes a practical use of these observations; recommending the attempt to make an artificial stone, for cover. ing the fronts of houses, instead of stucco; by admixtures of common sea fand and solutions of iron; and to preserve some of the softer kinds of stone in our buildings, by brushing them over with folutions of this kind.-By such means, he adds,
the venerable remains of that fine pile of building, Henry the Seventh's Chapel, might have been faved from the destruction with which we now see it ready to be overwhelmed.'
The observations and hints contained in this paper certainly deserve notice; and they will, we hope, incite some person, po refled of leisure and ingenuity, to prosecute the inquiry, in an experimental way.
NATURAL HISTORY. Article 14. Account of the Organs of Speech of the Orang
Outang. By Peter Camper, M. D. F.R.S. Jate Professor of Anatomy, &e. in the Univerfity of Groningen, &c.
It is a popular opinion among the honest tars, that monkies could speak if they would. Some travellers with greater probability affert, that the Orang Outang, who approaches somewhat nearer to our species, would be able to articulate if he thought proper.
Profeffor Camper has demonstrated, in the present paper, by an anatomical dislection of the organ of the voice, that articulation is rendered impossible in these animals, in consequence of the structure of that organ. From the nature and situation of those parts, in the Orang, in the Ape, and in the Monkey, he has proved that no modulation of the voice, resembling human speech, can be produced in these creatures: because the air, passing through the rima glottidis, is immediately loft in two ventricles, or hollow bags, in the neck, which are sometimes united into one; with which all these animals are furnished, and which have a communication with the mouth, through the said rima or slit: so that the air, as he obferves, * must return from thence without any force and melody, within
the throat and mouth of these creatures : and this seems to me the most evident proof of the incapacity of orangs, apes, and monkies, to utter any modulated voice, as indeed they never have been observed to do.' Article 20. Account of the Free Martin. By Mr. John Hunter,
F. R. S. Hermaphrodites, in general, seem to be casual and anomalous productions, or lufus nature : but in the Bovine race, as we Jearn for the first time in this paper, nature, for fome reason best known to herself, in the mysterious process of generation, seems to follow a regular System in the production of an hermaphrodite. It seems that if a cow bring forth twins, that are both bull-calves, or both cow-calves; each becomes respectively a perfect bull, or cow: but, on the contrary, if a cow produce two calves, one of which is a bull-calf, and the other apparently a cow; though the bull-calf becomes a perfect bull, the other calf is a kind of hermaphrodite, unfit for propagation. The animal, at least, is not known to breed ; never Thews the Jeast inclination for the bull; nor does the bull ever take the leaft notice of it.
This hermaphrodite is called the Free Martin. It has the teats and the external female parts of the cow: in other respects, it exhibits an unequal mixture of the two sexes; in which, at leaft in the three instances here described by the Author, the female is predominant. It resembles those imperfect or mutilated animals, the ox, or spayed heifer, in form, and other particulars. It is much larger than either the bull or cow : its horns are likewise larger ; being similar to those of an ox, whom it resembles too in its bellow, or voice.
MISCELLANEOUS ARTICLE S. Article 5. Account of Dr. Knight's Method of making artificial
Load-ftones. By Mr. Benjamin Wilson, F. R. S. It
appears from this paper, that the artificial magnets made by the late Dr. Knight were formed of a fubtle powder of iron, made into a paste with oil. A great quantity of clean iron filings were put into a large tub containing clean water ; in which, with much labour, they were agitated many hours, in order that the friction might break the filings into an impalpable powder. This would, on agitation, remain for a short time suspended in the water, which in its turbid state was poured off into a clean vessel, where the fine powder foon fubsided. In short, his process, with respect to the essential particulars, ap. pears to be the very fame with that invented by Lemeri, for the preparation of what is called his Martial Æthiops.
When a sufficient quantity of this powder had been collected and dried, it was made into a paste with linseed oil;-a subfance, which would supply it perhaps with more phlogiston than the small quantity it might have lost in the process; particularly in the drying. Being moulded into convenient forms, the pieces were dried before a moderate fire; where they acquired the necessary degree of hardness. He then gave them their magnetic virtue in any direction he pleased, by placing them between the extreme ends of his large magazine of artificial magnets for a few seconds or more, as he saw occasion.
• By this method, adds Mr. Wilson, the virtue they acquired was such, that when any one of these pieces was held between two of his best ten guinea bars, with its poles purposely inverted; it immediately of itself turned about to recover its natural direction, which the force of those very powerful bars was not sufficient to counteract.' Article 15. Account of the Effects of Lightning on Board the Atlas.
By Allen Cowper, Esq. Master of the Atlas East Indiaman, &c.
A conductor belonging to this ship was unfortunately not fixed at the time of the accident ( the afternoon of December 31, 1778) because lightning is extremely unusual at that time of the year, in our climate *. By the explosion, which was attended with a moft violent squall, very heavy rain, and large hail, a seaman in the main catharpins was struck dead; another in the main top was miserably scorched, and rendered senseless; and others received very smart ihocks. A fulphureous smell produced by it lafted all that day and night. Though the principal discharge appears to have been made near the main malt; no visible trace of the lightning could be perceived on that or the other masts, nor indeed any where else, except on the bodies and cloaths of the men through whom it pailed. The topgallant-mafts had no iron work upon them. Article 19. Account of a new Method of cultivating the Sugar
Cane. By Mr. Cazaud. This paper, which is translated from the French, appears to contain many valuable observations, made by a Sugar Planter at Grenada, relative to the best method of cultivating a plant which, Mr. Cazaud observes, is worth nine millions sterling annually to Europe. Many particulars, likewise, relating to it's natural history are here communicated, and are illustrated by a plate; without which the article would be unintelligible. One remark however of a general nature may be extracted ; to thew the immenfe difference occafioned by natural climate, in cases where we endeavour to produce the same temperature, in our artificial hot-houses.
* On that night and the following morning, a dreadful form passed over particular parts of England. In a place near the middle of the island, and not far from the sea, the lightning was frequent ; though the thunder could not be heard on account of the wind.
In the West India islands, from the time of the appearance of the first joint, the cane acquires a fresh joint nearly every week, for the space of 40 or 50 weeks; whereas in the King of France's botanic garden at Paris, M. Thouin Thewed the author a cane which had been brought from America in a pot ten years before ; and which, in all that time, had got only two joints out of the ground. To know a plant therefore thoroughly, says Mr. Cazaud, we should ftudy it in the climate to which it belongs.'
From the last article in this volume, the meteorological journal of the royal society, we learn that the variation of the needle, in July 1778, was 22 degrees, 20 minutes.
The MATHEMATICAL Articles will be reviewed in our
Art. VI. A flight Sketch of the Controversy between Dr. Priestley
and bis Opponents, or the Subjea of his Disquisitions on Matter and Spirit. In a Letter to a Friend. 8vo. Becket. 1780. HE ingenious artist, who has here undertaken a delinea
tion of the controversy between Dr. Priestley and his Answerers, professes in the most modest terms, to give only a Night sketch, or the mere outlines of the ground on which the metaphysical and religious combatants have exerted themselves. His outlines, however, are far from being destitute of strong light and shade; nor is a little warm colouring wanting occa fionally. He declares himself to be no disciple of Dr. Priestley, but nevertheless desirous of bearing a willing tribute to his merit;' particularly in exposing the partial, erroneous, and, in one or two well known initances, wilfully false accounts, that have been given of his doctrine, and its tendency.
On the present controversy, says our Author, Dr. Priestley
hath had the misfortune of being misunderstood, or misrepresented, beyond any other writer of rank and character in the literary world-unless, perhaps, we except the most learned and ingenious author of the Divine Legation of Mofes.”. Both have fallen under the invidious imputation of scepticism: and the religious profesions of both have been equally dfcredited either by ignorance, which could not comprehend the tenor of arguments that were not confined to the common and beaten track of speculation and logic; or by envy-which, when it fails to destroy a man's claims to learning and genius, will torture its invention, and Scripture too, to make his religion questionable.'
Dr. Priestley, he afterwards adds, ' has been accused of a design the most opposite to his wishes; and that is, to subvert the doctrine of a future state. His enemies--for as a' Presbyterian he hath many and as a Socinian more-have preci6