565 Monthly Register OF ARTS, SCIENCES, AND LITERATURE. *The Conductors of the AUGUSTAN REVIEW request scientific and literary men, and also Editors and Publishers, to favor them with authentic information relative' to inventions, discoveries, and improvements in Arts and Sciences; Notices of works preparing for publication, and of those recently published; which will be thankfully received, and communicated to the public in the subsequent Number, if sent to the publisher (post paid) before the 20th of the month. I. INVENTIONS, DISCOVERIES, AND IMPROVEMENTS, IN ARTS AND SCIENCES. Copper Ore. DR. THOMSON, in the last number of the Annals of Philosophy, has given a description of a new ore of copper, which has lately been brought from Mexico; but, as the specimens which he examined were both few and small, he conceives that this description may not be very correct. The colour was a verdigrise green, with a tint of blue; and the specific gravity 2.238. When a piece of this ore was dissolved in nitric acid, the colour of the solution was blue; but it became green when mixed with muriatic acid. When this mineral was treated in this manner, 24·1 grains of it afforded 61 grains of silica, and 10-5 grains of copper, when thrown down by a plate of zinc. The Doctor then observes, Now 10.5 grains of copper constitute 13.125 grains of peroxide of copper. The oxide in the ore was united to carbonic acid and carbonate of copper, as I have ascertained by experiment, and is composed of one atom acid, and one atom oxide. An atom of carbonic acid weighs 2.751; and an atom of peroxide of copper, 10. Therefore the carbonate of copper in the ore amounted to 16.736 grains. Hence the ore is composed of Carbonate of copper 16.736 Dr. Thomson had not a sufficient supply of the ore to enable him to ascertain whether the loss arose from an error in the method of making the experiment, or was owing to the pressure of water. Effects of Compression. From a paper by DR. BREWSTER, on the nature of double refracting crystals, read before the Royal Society, during some of its meetings in March last, it appears that the double refracting property may be communicated to various substances by means of pressure. In the course of his experiments, Dr. B. tried compression upon glass, fluor spar, crystals of common salt, animal jellies, and other single refracting bodies, and found it to succeed in communicating the property of double refraction. But upon calcareous spar, sulphate of lime, and some other refracting bodies, the same means were not attended with success. Bending a plate of glass also produced the same property as compression. Fine Arts. The nature and importance of the subsequent observations, taken from the Report of the Committee appointed to examine the works of the students, who were the architectural pensioners of the French government at the academy of Rome, in 1812 and 1813, will justify their insertion in this place. This report was made to the Class of Fine Arts of the French Institute, and printed in the Magasin Encyclopédique, and has also been translated for Number 215 of the Philosophical Magazine. These students are divided into two classes: the one comprehends studies of details, which they are to furnish during the first three years of their re. sidence, in order to shew their progress in the study of the art. The property of these works remains with the author. The labours of the other class consist in the restoration of ancient monuments, which the pupils ought to undertake during their resi. dence, and which they are to present to the government, in a finished state, at the expiration of their term of study. These restorations, which are regarded as the completion of their educa. tion, belong to the government. M. PROVOST, one of these students, directed his attention to the remains of the Temple of Jupiter Tonans; of which he has for the first time given a complete view. The most essential par ticulars in this new Corinthian model are: 1. The difference of breadth between the two intercolumniations of the angle; that of the anterior face having three modules, and that of the flank only two and a half. This appears to have been occasioned by the proximity of the ancient edifice denomi nated Tabularium. 2. The height of the column, which being ten diameters and a fourth, presents one of the most slender and elegant Corinthian proportions with which we are acquainted. 3. The nature of the Stylobate, which consists of a simple marble die, one diameter in height, without base or cornice, placed under each column. 4. Finally, the steps which are practised in the intervals between the dies, and which served to form the ascent from the ancient way to that of the peristyle of the temple. This method of placing the steps in the thick part of the pedestals of the columns had not before been remarked, except in the ancient Temple of Minerva, at Assise; and the Committee think it merits imitation in all cases, where the steps by which the temple is to be ascended cannot be brought in front of the peristyle. Among the other labours in which M. GAUTHIER has been em. ployed, is the restoration of the Temple of Peace, which, from the magnificent arrangement of the plan, the colossal dimensions of the masses, and the means of construction employed to ensure the necessary solidity, has at all times fixed the attention of studiousarchitects. In 1813, M. Gauthier followed the excavations with the greatest care, and made accurate drawings of every vestige which appeared calculated to throw light on its decoration. The results of his inquiries are contained in twelve drawings; and the Committee consider the monument entirely restored, with all the details of the orders by which it is decorated, both externally and internally. The most remarkable parts of this restoration, because they are entirely new, are stated to be the following: 1. The plan, section, and external elevation of the portico, which ranged along the whole eastern part of the edifice, and preceded its entrance on the side of the Colyseum. The compartments of the pavement are in cipoline and yellow antique marble, and those of the groined arches are adorned with caissons. 2. A more exact and complete plan than had previously been given, of the three naves constituting the body of the temple, with all the compartments of its magnificent pavement, composed of the most valuable marbles; as the violet breche, yellow antique, green granite, porphyry, and serpentine. 3. The entire decoration of the grand circular niche which occupies the middle of the north flank. The nature and execu. tion of the fragments of this decoration, lead the author to conjecture that it has undergone changes at the time the edifice was converted into a church. 4. The lateral entrance made in the flank of the temple, opposite this niche, and which, therefore, ought to have looked into the via sacra. 5. The measurements of the grand column now raised upon the plan of St. Mary Major, which presents the singularity of being thickened about one-third up the shaft, and very little diminished at its upper part. This appears to have been adopted in order to give more strength to the arch, and presents more resistance to the burden it had to support. 6. The most unexpected of these restorations, and on that ac count the more valuable, is that of the arch which covered the central nave of the edifice. It has been drawn from the numerous fragments discovered in the excavation, and collected and combined by M. Gauthier, so as not only to reproduce the arrange. ment of the various compartments of which the whole was com posed, but all the ornaments in stucco with which they were enriched; so that there remains nothing more to be desired upon this most important part of the edifice. The other species of marks included in the report of this Committee, are the restorations of ancient monuments made for the government, by those who have completed their architectural studies under its protection. The works here reported upon, are those transmitted by M. M. Leclerc and Huyot. M. LECLERC chose the Pantheon as the subject of one of these restorations; and in a series of twenty-one drawings, executed with great skill, he has succeeded in giving a more complete work than any which had previously appeared, and which is in many respects new, in consequence of the numerous discoveries with which he has enriched it. The Committee in their report enumerate thirteen of these discoveries, which they deem the most important; and which, in conjunction with others, induced M. Leclerc to draw the two following conclusions. 1. That from the original construction of the Pantheon, it was designed to serve as a temple; and never formed part of the baths of Agrippa, with which it has not any direct communication. 2. That the Corinthian order by which the entrance portico and the interior are decorated, dates from the epoch of the primi tive construction of the edifice, and that these ornaments are not additions made to the circular part of the temple, subsequent to the time of Agrippa, as has generally been supposed. To these observations, the Committee add, that M. Leclerc has endeavoured, with the most scrupulous accuracy, to give the true character to the ornaments, and to present the arrangements, and even the colour of the materials: that he has added satisfactory explanatory notes; and that the drawings are executed with so much perfection, as to make them worthy of being regarded as models of their kind. The restorations presented by M. HUYOT, are those of the celebrated Temple of Fortune and the Forum of the ancient city of Præneste. He has illustrated his plates by a descriptive memoir; and all the three orders of architecture were used: the Doric in the lower part of the Forum, the Ionic entered into the decoration of the edifices dependent on the Temple of Fortune; but the Corinthian is that which is the most frequently met with in the buildings of Præneste, and, though often repeated, both its proportions and ornaments are always the same. The various observations which the author made during his investigations of the subject, lead him to conclude, that the monuments of Præneste, having both by the manner of their construction and the style of their architecture an evident analogy with the Temples of Hercules at Cori, and of the Sybils at Tivoli, with the Tabularium of the capital, and other remains of antiquity spread over Etruria, their erection must be dated from an epoch at least contemporary with the above buildings, that is, at a period greatly anterior to the foundation of the empire; and, consequently, that their style of architecture may give an idea of that which was brought by the Greek colonies when they came into Italy. Flexible Sand-Stone. A stone of this nature has lately been brought from the eastern coast of China to London. Its colour is partly white and partly yellow. It is soft, opaque, and composed of extremely small particles or grains. Specific gravity 1.6825. This stone differs from the flexible sand-stone of South-America, both in its external properties, and in the effect of water upon it. DR. THOMSON analysed about twenty grains of it, and found it to consist of the following ingredients, viz. Silica. Lime with a trace of iron. 19.08 0.62 0.30 20.00 Hydrophobia. Such is the dreadful nature of this malady, that every mode of treatment that appears to have been employed with success, deserves the most extensive publicity. The following account from a gentleman at Venice to his friend in London, is given as a discovery of this kind. |