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lent artificial Pyrmont Water. The subsequent improvements in the apparatus, which we have seen and used, principally confist in adding a neek, fitted with a ground stopper, to the fide of the middle vessel ; through which the operator may at any time draw off, and taste the impregnated water, in the course of the process. The stopper of the uppermost vessel has likewise a small perforation running through it; so that it may at all times be kept in its place, without any danger of explosions ; and the uppermost liquor is not liable to so great a loss of the fixed air, with which it may have been impregnated, as it is subjected to when the communication with the common air is leit more open.

During a course of experiments, made with this apparatus, in which it was necessary to carry on the same process for several days, we have wished that this dislipation could be ftill fure ther diminilhed, or totally prevented. This end might be answered, by discovering some easy method of keeping the void space in the upper vessel constantly occupied by fixed, instead of common, air; or by the discovery of some tasteless fluid, immiscible with, and lighter than water, and impervious to fixed air, if there exists such a fluid; which might be poured on the surface of the uppermost liquor, and intercept its communication with the atmosphere. We have failed in applying sweet : oil to this purpose, which is supposed to absorb fixed air with

great difficulty. In the space of two days, its lower surface was seen ftudded with innumerable small bubbles of the fixed air, which had deserted the water, and were soliciting entrance into the oil, which was soon afterwards found to be impregnated with it. Perhaps this defideratum may be hereafter fupplied through the ingenuity of others. In operating on small quantities, for the purpose of experiment, mercury is excellently adapted to the impregnating any Auid with its maximum of fixed air, on immerging into it the neck of the invested vial, which receives its fixed air by means of Dr. Priestley's apparatus.

We shall only further add, that if a proper flexible substance could be discovered, or a common bladder could be so prepared, by oiling it, or other means, as to be rendered impervious to fixed and common air; it might answer the above-mentioned purpose effectually, either by tying it, empty, to the perforated stopper, at the beginning of the process, after the upper vessei has been filled with the water; first adjusting the length of the bent tube, and the quantity of the effervescent materials, so as that, after the uppermost vestel has been filled with the water, a considerable portion of fixed air may ascend through it into the bladder; or by previously introducing into the bladder a proper quantity of fixed air, expelled from materials contained in a vial.

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The expedient might be rendered more fimple, and perhaps not much less effectual, by only suffering the common air contained in the uppermost vessel to ascend into the bladder ; for as that fluid can probably dissolve, or suspend only a determinate and moderate quantity of fixed air ; when it were once saturated with it, it would no longer deprive the liquor in the uppermoft vefsel of any part of the fixed air which it had imbibed : whereas, even through the perforated stopper of Mr. Parker's apparatus, small as the aperture is, fresh portions of atmospherical air necessarily continue to enter the upper vessel, in proportion as the fixed air is condensed in the middle glass; and consequently rob the liquor of a part of the fixed air, with which it had been impregnated *. These expedients are not wanted in the common process for impregnating simple water ; but some contrivances of this kind would be of great use in certain other processes, of much longer continuance, as we have experienced. Article 9. Experiments on a new colouring Substance, from the

Island of Amsterdam, in the South Sea. By Mr. Peter Woulfe, F, R. S.

This new colouring substance is of the resinous kind, and has a good deal of affinity to Annotta. It gives out its colouring matter to spirit of wine, which it tinges of a yellow colour. It is dissolved likewise in oil of turpentine, vitriolic æther, and in solutions of fixed and volatile alcali, and of soap. By these solutions, folk, woollen-cloth, and linen, receive various shades of yellow and orange; which, however, are discharged on boiling the dyed substances in soap and water. It can therefore be of use only in dying lilk, and woollen cloths; for which purpoles, the Author observes, we are already furnished with good dyes. Few colouring drugs, he adds, go so far in dying, and none dye so speedily ; especially when a solution of soap is employed, which may perhaps be used with advantage, as the folvent for several other colours.

PHYSICAL GEOGRAPHY. Article 2. An Account of Two Giants Causeways, or Groups of

prismatic basaltine Columns, &c. in the Venetian State in Itais, & C. By John Strange, Esq; F. R. S.

• Might not the Caoutchouc, or elastic resin of Cayenne, if it could be moulded into a thin, and yielding bladder-like form, be well adapted to this particular purpose? It possesses the excellent quadity of reGfting the action of almost every known fluid, except ather. The bladder, however, in another respect, would be preferable ; onless we could diminish the remarkable elasticity of this resin, which, in the present case, is rather disadvantageous. An account of M. Macquer's Chemical Examen of this substance will be found in the Appendix to our 46th yolume (1772), p. 689.

In our last Appendix [Vol. lii. page 619), the Reader will find an account of the observations lately made by M. Delmarest, on the origin and nature of the Basaltes in general, founded on an accurate examination of the numerous and extensive groups of this stone spread over the provinces of Auvergne and Velay in France. In this Article Mr. Strange particularly de. fcribes two groups of prismatic basaltine columns, discovered by him in the Venetian state ; illustrating his descriptions by two topographical views, as well as other drawings relative to the subject; and adding fore pertinent observations on the characters and formation of the e and other similar vulcanic concretions, as well as on the physical geography of the countries, in which they are found.

With respect to the origin of these bodies, he contraverts the common opinion of the lystematical mineralogists, who generally ascribe their formation, as well as that of the greater part of lapideous folids, to a deposition of stoney matter from an aqueous fluid : on the contrary, he thinks that it is evident, from various considerations respecting their structure, fituation, and other phenomena, that they are chrystallizations, or concretions of a particular kind, and generated immediately from an igreous fluid:' as they are not only peculiar to vulcanic tracis of country, but differ in every respect from the common chrystals produced, Jiratum super firatum, by the flow and successive precipitation of the stoney particles concained in water. He accordingly attributes their formation to some intrinsic principle of organization, operating on an ignited fluid; on the concretion, or consolidation of which, the organic principle may be fupposed to have operated simultaneously in a large mass, and to have produced these bodies in the same manner, as a linget of metal concretes at once in the mould.' This opinion is well · supported by various obfervations, but for these we must refer the

Reader to the Article itself; the general doctrines contained in which will receive a stronger confirmation from a more particular account of the vulcanic phenomena in the provinces of · Auvergne and Velay, which the Author proposes hereafter to communicate to the Society. .

MUSIC.
Article 5. Account of a Musical Instrument, which was brought by

Captain Fourneaux, from the Ijle of Amsterdam, in the South
Seas, to London, in the Year 1774, and given to the Royal Society.

:'y Joshua Steel, Esq.
Article 6. Remarks on a larger Sy/lemn of Reed Pipes, from the Isle

of Amsterdam, with some Observations on the Nose Flute of Otaheite. By the same. In these two Articles the Author has displayed a minuteness of investigation, and a profusion of ancient inulical erudition, on

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a subject ill adapted, in our opinion, to so laboured and scientifica discussion. The musical instrument imported from the Ine of Amsterdam, appears to us to be neither more nor less than the Lupiye, or fipula Panis ; the result of the first rude and inartifi. cial attempts to produce something like music, which have been made in most countries of the world, where reeds or canes grew. The various arbitrary, and indeterminate sounds, given by the reed pipes of the barbarous inanders of the South Seas, nearly all of which we would undertake to produce by the weaker, or stronger blowing through a penny whistle, are here seriously, and scrupulously, compared with the diatonic and chromatic genera of the polished Greeks. Such a comparison, were not the Author perfectly serious throughout the whole of these two Artiticles, might appear as an intended solemn mockery of ancient wisdom. The Author acknowledges, however, that the South Sea instrument does not, from his experiments, appear capable of furnishing sounds corresponding with the dieses, or quarter tones, in the enharmonic genus of the ancients. From hence we are very naturally led to conclude, that the enharmonic division, at least, of the Tetrachord, is yet unknown to' our musical brerbren among the Antipodes.

Nevertheless, that our good friends, the Otaheitans, how lame soever they may be in theory, or in the fabrication of musical instruments, practise the intervals of the diefis, and Atill minuter divisions of the tone, we have some reason to conclude, from the testimony of a sober and discreet person, who has a tolerable good ear, and has heard Omiah sing one of his country songs. The melody, in fact, seemed to be wholly enbarmonic - flubbering and sliding from found to sound by such minute intervals, as are not to be found in any known scale, and which made it appear to him as muficmific could be called music, of another world. According to Mr. Sieele, ibe nose fute of Otaheite affords, with a moderate blalt, four sounds which proceed, in an ascending series, by the intervals of a semitone, a tone, and a semitone. The Author has given us two specimens of melody composed by himself, on this scanty scale, and written according to our notation. We violently suspect, however, that these tunes would scarce be recognized, as jult specimens of his country music, by Omiah ; from whom we think our Author might have derived more knowledge of this fubject, by only listening to one of his songs, than by thus learnedly conjecuring what, and how, his countrymen fing, or may pomibly fing, a priori.

MISCELLANEOUS ARTICLE S. Article 12. Experiments and Olfervations in an hiated Room. By Charles Blagden, M. D. F. R. S.

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was in a dry boiling watee Do&or was accoDr.

These experiments were made by Dr. George Fordyce, in a fuite of rooms heated by flues in the floor; in one of which the air was in a dry state, and in another was loaded with moisture, by pouring boiling water on the floor. In some of these experiments, in which the Doctor was accompanied by the Honourable Captain Phipps, Mr. Banks, Dr. Solander; and the Author, these gentlemen breathed, without suffering much inconvenience, in a room heated, at different periods of the experiment, from 150 to 210 degrees of Fahrenheit's thermometer ; while the heat of their bodies rose very Jittle above its usual state. Their watch chains, however, and other pieces of metal, felt so hot that they could scarce bear to touch them for a moment. It appears too that the heat of the room was very sensibly diminished by their entrance into and continuing in it. We must refer to the ar. ticle itself for the many other curious phenomena that were observed in there trials, and which are too numerous and contain coo many circumstances, to admit of a satisfactory abridge. ment.

From the whole of these experiments the Author concludes that the human body has a power of destroying heat ; and that this power, as well as that of generating heat, according as the circumstances of its situation require, can only be referred to the principle of life itself, and is probably exercised only in those parts of our bodies in which life seems peculiarly to reside.'_That some process exifts in living animal bodies, by which heat is produced, and which is different from the common processes of fermentation, putrefaction, and mechanical attrition, as carried on among the particles of inani. mate matter, is very evident : but by attributing the heat thus generated to the principle of life,' nothing more is donc than the giving a name to the unknown cause of it ; for no one is ignorant that this power does not exist in a dead carcase. --The Reader will meet with some reflections of ours on this subject, in our Review of Dr. Franklin's Letters, &c. in vol. 42, April 1770, page 301, &c.

As to the other power, which living animals are supposed to pofiefs, of desiroying heat, when breathing in a medium conliderably hotter than their bodies; we shall only observe (not meaning, however, to deny the reality of it) that the Author seems to have almost wholly overlooked a circumstance which appears to deserve consideration in the present case ; at least with regard to the quantum or intensity of this refrigerating power in living animals. A considerable part of it, with respect to the human body, may very naturally be ascribed to the comparative coldness of a bulky mass of solid and Auid

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