accommodate the motion in drawing the arms in a direct line with each other towards the straight edge, D, which is done by the revolution of a small roller in a spiral cut in the wheel H. This roller is screwed on a projection G, attached to the middle of the lower arm B. The wheel, H, has also cut on its edge granulated teeth in which a pawl, I, is made to catch, propelling the wheel around when actuated by the thumb-piece, K, with the pressure of the thumb of the left hand, and it is sustained in its position by a pawl, L, as the pressure is continuously repeated. The box, M, contains a spring which throws the double rule, A, back to its former position when relieved from the pawl L. On a raised ledging of the bedplate, P, there is a graduated scale with figures, to enable the operator to set his distances as he may require between each line, which is done by a short sliding bar secured by a screw, G. O is a raised ledging on the inner rule which guides and steadies the protector in its motion. The spiral movement described is attached to the bed-plate P (the lattter being planed level), and is adjustable upon the face of the stone as may be required. In using this guide the operation is very simple, and requires but little practice, the guide being so constructed as to produce the distances between each crack mathematically correct. It can also be set by the scale so as to obtain any number of cracks to the inch from eight to forty-eight. When using this instrument, the palm of the left hand is pressed firmly upon the bed-plate, P, on which the movement is fixed, and, after having marked with the diamond as often as required, the thumb-piece, K, is pushed by the thumb of the left hand as far as it will go, then immediately relieved. This pressure is repeated until the back of the double rule touches the straight edge, D, when the forefinger of the left hand presses the pawl, L, and the spring in the box, M, then instantly extends the double rule to its first position. A The small diagram shows the construc tion of the "protector." A represents the stock or protector, in which is inserted a steel bar, B, containing the diamond C. A is a shifting guard, upon which the protector is made to slide between the double rule or tramway. This guard is adjustable, and secured in its position by a thumb-screw D. E is a rod which is pressed upon the bar, B, containing the diamond, C, by a spring, which pressure is increased or diminished by a screw, H, at the top of the handle, G, in accordance with the nature of the burrs and depth of dress required. This protector is drawn through the double rule or tramway, the same as a pencil in ruling a slate. The operation is so simple that a boy could operate with it blindfolded.-The Artizan. 1 The block has been kindly lent by the Editor of the Artisan. REVIEWS OF BOOKS. The Universe; or, the Infinitely Great and the Infinitely Little. By F. A. POUCHET, M.D., Corresponding Member of the Institute of France. Translated from the French. London: Blackie & Son. 1870. Science should be, and has given us a treatise on Nature generally, which is unquestionably the finest work of the kind ever published in this or any other country. The author's object in writing the book was to extend to the utmost of his power a taste for Natural Science, and in the preface he admits that his book is not "a learned treatise, but a simple elementary study, conceived with the idea of inducing the reader to seek in other works for more extensive and more profound knowledge." The volume is, in point of fact, a magnificent landscape of natural phenomena. Everything is Turneresque and broad and grand; there is no taint of pre-Raphaelitish detail about it. To give an idea of the multitude of subjects dealt with by the author we quote the following headings of the several "books" into which the work is divided. These are-the Invisible World; the Architects of the Sea; Insects; Ravagers of Forests; Protectors of Agriculture; the Architecture of Birds; the Migrations of Animals; the Anatomy of Plants; the Physiology of Plants; the Seed, and Germination; Extremes in the Vegetable Kingdom; Migrations of Plants; Formation of the Globe; Fossils; Mountains, Cataclysms, and Upheavals; Volcanoes and Earthquakes; Glaciers and Eternal Snows; Caverns and Grottoes; Steppes and Deserts; the Air and its Corpuscles; the Stars, and Immensity; the Solar World; and, lastly, Monsters and Superstitions. Indeed, it will be apparent that M. Pouchet's volume is, as its title indicates a history de omnibus rebus et quibusdam aliis, in so far as concerns the objects usually embraced by the study of Biology. Perhaps it would have been wiser had a more limited area been chosen, but with such a field before him—a field, too, in which he himself has done so much, and such good work-M. Pouchet has achieved all that could be done in justice to each department he has handled; and being master of a literary style such as very few scientific men possess, he has written one of the most attractive and graphic chronicles of Nature's operations which we have ever had the fortune to meet with. Here and there we notice passages and illustrations which have been inserted, we should say, in the exercise of poetic or artistic license rather than from a conviction of their veraciousness. This we regret; it was to have been avoided if possible, but we presume that M. Pouchet, on the whole, gives a grain of credence to the statements of the kind which his book contains, else we should not find him giving a description of the gigantic cuttle-fish seen in 1861, off the Canaries, by the captain of a French vessel; and, on the same ground, we would explain the appearance of a handsome engraving illustrating this huge" polypus," which is here made almost as large as the steamer, which apparently, as a matter of precaution, is giving the monster a wide berth." There are, however, very few such defects in this magnificent volume. Tout au contraire, the facts narrated are well established, and the illustrations, many of which are exquisitely coloured, are such as have never before appeared in any treatise on science. The engravings are so numerous that it is hardly possible to open any of the nearly 800 pages of which the work consists without coming on some elegantly-designed and wellprinted woodcut. Of the other mechanical features we can truly say that, in binding, paper, and typography, the publishers have spared no expense, and have in consequence produced a book which in point of luxurious ornamentation cannot be surpassed. : Of the contents of the work there is not much to be said critically the mere outlines of natural history have been sketched. But there are some of the chapters which contain matters not hitherto brought before the English reader of popular scientific books. Of these two are particularly worthy of notice those on "the air and its corpuscles," and on "monsters and superstitions." Both these chapters will be read with interest by educated persons of even average intelligence. In the first, the author, who we need not say is the well-known advocate of the doctrine of spontaneous generation, indulges in a telling diatribe against M. Pasteur and the other modern supporters of panspermist doctrines. And, in our opinion, M. Pouchet has by far the best of the argument; for, so far as positive facts go, all are on his side, and none on M. Pasteur's. Hear what M. Pouchet says in regard to the supposed universal presence of organic germs in the air : "There are plants which only appear under circumstances so exceptional and so extraordinary, that the mind revolts at the idea of their tiny seed loading the atmosphere century after century in order at long intervals to fertilize some imperceptible part of the globe. This would be inutility in immensity. A fungus is known which never grows except on the bodies of dead spiders. Another only appears on the surface of horses' hoofs in a state of putrefaction. One little parasite of the same family-the Isaria of the Sphinx-has hitherto only been observed on certain nocturnal moths. The chrysalides and larvæ of these are never attacked by it; other species infest them. Unless one possessed the imagination of a Bonnet is it possible to suppose that Nature would uselessly have burdened the air of the whole globe for the mere purpose of scattering seed on the bodies of a few spiders and moths; and that there was always a stock ready for the perfect insect, its chrysalis, and its larva? Still more curious facts are known; for instance, that of a fungus never found but on the neck of a caterpillar of tropical countries. It is always solitary on this, and of enormous size in proportion, being often four to five inches high." M. Pouchet's argument as to what Nature would or would not do is, of course, of no scientific weight, as we know that Nature is horribly wasteful of her organized products, but there are other facts in this chapter which the panspermists never can fairly get over. The chapter on Monsters is a most unique and curious account of the strange creatures described as actual entities by the older writers, and especially in the works of Albertus Magnus, Aldrovandus, and others. The illustrations are bizarre and amusing examples of the credulity of our forefathers. The account of the Grottoes and underground caverns of different parts of the globe are brief, but are singularly interesting, and are accompanied by some engravings of remarkable beauty, two of which, one representing the Mammoth Cave, and the other the curious Proteus of Carniola, we have been enabled through the courtesy of the publishers to reproduce (see p. 93). Altogether the book is most praiseworthy, and the translator, whose name is not given, has done his part of the work with very great skill and carefulness. The Body and Its Health: a Book for Primary Schools. By E. D. MAPOTHER, M.D. London: Simpkin & Marshall. DR. Royal College of Surgeons of Dublin, has here given us R. MAPOTHER, the Professor of Physiology in the a very elementary school book on general physiology and its application to practical hygiene. The style and plan of the little volume are excessively simple, except in a few occasional passages, where the author expresses his opinions of the duty of the State to the people-not the sort of thing most intelligible to young, very young, folk at school. The volume is worthy of commendation, and we hope some of our primary schools will adopt it. 30s. cl. 15s. cl. ENGLISH. Crombie's Lichenes Britannici, &c. 12mo. 4s. 6d. cl. Günther's Record of Zoological Literature, 1868. Vol. V. Lawlor's Pilgrimages in the Pyrenees and Landes. 8vo. Letheby's Food, its Varieties, Chemical Composition, &c. 6s. cl. Loudon's Instructions in Gardening. New Edition. 12mo. 3s. 6d. cl. Stainton's the Simiana of Southern Europe. 8vo. 16mo. cl. Student (the) and Intellectual Observer. Vol. IV. 8vo. 10s. Veitch's Handbook for Nurses of the Sick. 12mo. 2s. 6d. cl. FRENCH. Cahiers d'Histoire naturelle. Par M. Milne-Edwards et M. Achille Compte. Nouvelle Edition. le Cahier. Zoologie. Paris. Victor Masson. De l'Action physiologique et des Propriétés antipériodiques des Sources Ferro-arsenicales de Vals. Par M. V. Ollier. Lyon. Vingtrinier. Des Resections des grandes Articulations des Membres. Par M. L. Ollier. Lyon. Vougtrinier. Etude d'un Cas d'Hermaphrodisme bisexual imparfait chez l'Homme. Par M. E. Gougon. Paris. G. Baillière. Hygiène militaire. Casernement chauffage, Bains, Alimentation, aperçu comparatif du Régime alimentaire dans les Armées d'Europe hygiène morale. Par le Docteur J. Douillot. Paris. Rozier. La Philosophie Zoologique. Par M. V. Meunier. Paris. Paguerre. Les Merveilles célestes, Lectures du Soir. Par M. C. Flammarion. 3e Edition. Paris. Hachette. Les Sesqui-fluoferrates. Par M. J. Nicklès. Nancy. Sordeillet. Note sur la Méthode d'Aspiration continue et sur ses Avantages pour la Cure des Grandes Amputations. Par M. Maisonneuve. Paris. Raçon. ITALIAN. Elementi di Scienze naturali e d' Igiene ad Uso dell Scuole normali, magistrali, techniche e popolari, esposti secondo il ministeriale programma 10 ottobre 1867. Per cura del Dott. Ant. Ferrario. Lodi. Costantino Dell' Avo. Fondamenti di Fisiologia dell' Uomo di Hermann Ludimar, con l' Aggiunzione della Fisiologia speciale dei Mammiferi. Del Dott. Giovanni Paladino. Napoli. Perrotti. Lezioni di Agricoltura del Cav. Comm. Professore Pietro Cuppari. Nuova Edizione, arricchita di molte aggiunte relative all' agricoltura italiana. Vol. II. Agricoltura speciale. Pisa. Flli. Nistri editori. Manuale di Anatomia descrittiva Veterinaria. Del Prof. Felice Perosino. Parte I. Osteologia, dedicata alla solennità del centenario della R. Scuola di medicina veterinaria di Torino, addì 1 settembre 1869. Torino. Derossi. Manuale di Patologia generale, compilato sulle Lezioni di Antonio De Martino da Teodosio De Bonis. Napoli. Perrotti. CORRESPONDENCE. It is distinctly to be borne in mind that we do not, by inserting letters, convey any opinion favourable to their contents. We open our columns to all, without leaning to any; and thus supply a channel for the publication of opinions of all shades. No notice whatever will be taken of anonymous communications. DR. MOLLOY ON THE BIBLE AND GEOLOGY.-From Dr. MOLLOY. SIR,-I do not mean to trouble you with a defence of my work on Geology and Revelation against the critical remarks that appeared in the last issue of your journal, but there is one error into which the reviewer has fallen, which I trust you will allow me to correct, as it seems to involve a charge of dishonesty. It is alleged that I have "ignored the geological evidence which bears upon the antiquity of the human race, and, a little further on, the writer hints, clearly enough, that I have done this for the purpose of misleading my readers, inasmuch as the evidence in question is unfavourable to my cause. He says, "treatises like that of Dr. Molloy, in which the Bible is made to tell the required story, and in which so much of scientific truth as is demanded is told and no more, are the stepping-stones of scepticism." Now I have distinctly stated, in my introductory chapter, that there are two points of contact between geology and revealed religion, the one being the antiquity of the earth, the other, the antiquity of the human race. The first of these two points I take for the subject of the present volume, and, in the last paragraph of my book, I announce my intention of discussing the second, as soon as I can find leisure and opportunity. This being so, it is plainly not quite fair to say that I have "ignored the geological evidence for the antiquity of man, much less is it fair to insinuate that I have dishonestly suppressed it. The reviewer maintains that the omission of this evidence is "a deep flaw in Dr. Molloy's argument, and one which indeed renders his reasoning absolutely without foundation." I regret he should entertain this opinion, and I have little hope of converting him to my views, but I may be allowed to observe that the antiquity of man AMPHISAURUS AMBLYODUS.-From Mr. T. P. BARKAS, F.G.S. SIR,-Among the recent fossil remains obtained from the Northumberland Low Main coal-shale is a jaw which I have reason to believe has not yet been named or described, and which certainly has not yet been recorded as present in these northern coal-fields. My first introduction to the new reptile was through the kindness of Mr. Ward, of Longton, Staffordshire, in whose cabinet I saw, for the first time, a large portion of a jaw with very peculiar teeth. The length of the jaw was 4 in., and the teeth, which were eight in number, were placed at irregular intervals. Within the last few weeks I have obtained a similar jaw from the Northumberland coal-measures; it is in two portions, one being 3 in. long, and the other, 1 in. In these fragments there are eight teeth, and the impression of one tooth. Each tooth is in. long, they rise almost perpendicularly from the jaw, and are of nearly uniform diameter to within in. from the apices: at that distance from the summit they turn off at an obtuse angle, and the apices of the teeth are very obtuse. A tolerably accurate representation of the form of the tooth may be obtained by placing the forefinger erect, and bending it at the upper joint. Megalosaurus Bucklandii, plate 62a, fig. 6a, Owen's Odontography, somewhat resembles the tooth, but, unlike the tooth of Megalosaurus, which is flattened and denticulated, the teeth of the new reptile are perfectly circular and free from denticulations. The depth of the jaw is in., the thickness at the anterior extremity is in., and towards the posterior extremity, in. The teeth are arranged at irregular intervals, occasionally the space between them is in., and, in other cases, the teeth are nearly in contact. Each tooth is marked by distant longitudinal striæ, and they are strongly plicated near the base. The specimen in the possession of Mr. Ward and that in my possession are both mandibles, and having reason for believing that nothing more is known of the reptile, I propose provisionally to name it Amphisaurus amblyodus, the generic name signifying that it is a saurian of doubtful affinities, and the specific name that the teeth are not only obtusely pointed, but that they are also bent near the summits at an obtuse angle. On the slab associated with the jaw of Amphisaurus amblyodus there are a ridged bone which has the appearance of a fragment of a scapula, and a large nodule of coprolitic matter. Gigantic American Flowers.-Dr. B. Seemann writes as follows to the Gardeners' Chronicle:-Tropical America enjoys the preeminence of producing the largest floral development in a good many natural orders, there being the Victoria regia amongst Nymphæaceæ, the Brugmansia candida amongst Solanaceae, the Lasiandra macrantha amongst Melastomaceæ, the Sapranthus Nicaraguensis amongst Anonaces, the Godwinia gigas amongst Aroideæ, &c. Until I discovered Sapranthus Nicaraguensis, tropical Africa was supposed to possess the largest Anonaceous flowers in existence (Monodora), and now I learn from your columns that Dr. Welwitsch has found in Africa an Aroid even larger than my Godwinia gigas. As I "out-monodored" him in the Anonaceae, of course I must not grumble if he "out-godwinias me in Aroideae; but I still trust that when actual measurements are produced, America may yet come off victorious in the question. There is no reason to assume that the few specimens of Godwinia measured in Nicaragua were the largest ever produced in the country, and there is every reason to assume that if my specimens, after suffering somewhat in their passage to England, attained the past season dimensions equalling within a few inches those of the plants in Nicaragua, they may exceed them even if Mr. Bull really does begin to cultivate them. SCIENTIFIC SOCIETIES. Secretaries of Societies will oblige us by regularly forwarding "Abstracts of Proceedings; " and they would do much to enhance the interest and success of their meetings if they would enable us to publish in anticipation "notices of papers to be read." ROYAL SOCIETY. (Meeting of the 13th inst. continued from page 74.) VII. On the Occurrence of Enstatite in the Busti Aerolite.-Besides the augite already described there occurs in this meteorite another silicate which constitutes its most important ingredient. The augite is chiefly found in the nodule with the calcium sulphide, and is found more sparsely in the remaining parts. Associated with it throughout, and otherwise forming the chief mass of the stone, is a mineral which, in microscopic sections, presents the appearance of a number of more or less fissured crystals of varying transparency, some clear, some nearly opaque, and usually presenting a not very unsymmetrical polygonal outline. Those crystals are imbedded in a magma of finegrained silicate, itself often entangled in an irregular meshwork of opaque white mineral. Amongst these ingredients, when mechanically separated, what seems to be three different minerals can be distinguished. The rarest of them is transparent and colourless, and very irregular in the form of its fragments; a second is of a greyish-white colour, translucent, and offering an even less hopeful problem to the crystallographer than that presented by the first. The third is an opaque mineral with a distinct cleavage following the faces of a prism of about and with a second imperfect cleavage perpendicular to the former. From a few fragments of the two former kinds some measurements were obtained, which conduct to the conclusion that, like the last-mentioned silicate, these minerals are enstatite. The angles 1 0 0, 1 1 0 are 46° 25', and 1 0 0, 1 0 1, 41° 34'. 88.35 91-27' Chemical analysis confirmed the identity of these three minerals by showing them to be enstatite under different aspects. When lime is absent it presents itself as a simply prismatic mineral, the dark grey tabular variety. When lime is present, though to an amount less than two per cent., the crystalline structure becomes more complex. The augite may perhaps be tesselated, as it were, in the enstatite, somewhat as this latter mineral has been shown to occur intercalated to a small amount in layers of augite. I did not succeed in establishing this point, however, by an examination of microscopic sections of this mineral. The crystalline fragments frequently show, when examined by polarized light, a composite structure, the principal sections of the different parts of the mineral being disposed at every angle of mutual inclination. The analysis of these minerals yielded the following numbers : Dark Grey Tabular Variety. Transparent White Variety. As in the case of the augite, the soda is probably derived from the hydrogen chloride; the iron occurs partly as metal, minutely subdivided, partly as oxide combined with the magnesium silicate. In each case the bases slightly exceed the amount required by the formula of enstatite. On comparing these with known analyses, and those which I shall shortly submit to the society, it seems highly probable that, where the conditions under which a meteoric silicate has been formed were such that silicate acid was present in excess of that required by the formula of enstatite, this acid remains uncombined, in the form of crystallized silica with the specific gravity of a fused quartz, and that where magnesia and other bases are in excess, a basic silicate with the formula of olivin absorbs the supplementary portion of these bases. Calcium, when present, would convert into augite its equivalent ratio of what would otherwise constitute enstatite, and it is possible that this is true even when this element is distributed in small quantities throughout the mass. No alumina, and consequently no feldspathic ingredient, has been detected in this meteorite. VIII.-Composition of the entire Meteorite.-With the view of determining the different ingredients, minerals present in the Busti meteorite, fragments and dust from the neighbourhood of the nodule of sulphide and augite were analyzed. The mineral was treated with hydrogen chloride, carbon disulphide, and potash, which removed 16 873 per cent., leaving a residue of 83-127 per cent.; the composition of these two portions, soluble and insoluble, is given below :— Soluble Portion. Insolable Portion. The ratio of the silicic acid to the magnesia and lime in the latter analysis corresponds with the composition ( Mg Ca) O, SiO.. Regarding the calcium of the white and grey varieties of enstatite to be present as augite intercalated with the enstatite, we may assert that while all the silicates of this meteorite present the typical formula MO, SiO2, three equivalents of the rock near the nodule may be treated as composed of two equivalents of augite and one of enstatite; in other parts of the stone the latter mineral predominates. A formula for the augite with magnesium and calcium in equal proportions would no doubt more truly represent its composition; it is, however, as impossible to separate the enstatite intercalated with it as it is to remove this mineral when blended with the enstatite. IX. Solubility of the Minerals of the Busti Meteorite.-As it appears of importance to determine the degree to which these meteoric minerals were soluble in acid, the augite and enstatite were submitted to this solvent action. Digested for several hours at 100° C. in hydrogen chloride diluted with half its volume of water, and subsequently in potash for some hours to remove the free silica, the angite and each of the three forms of enstatite proved to be acted upon, the results in all cases showing that the acid simply exercises a solvent action on the mineral, without separating it into two or more distinct silicates. The subjoined table gives the results of the experiments. The degree in which the acid dissolved the mineral was due to the more or less complete trituration of the material before treatment. In one case, for which the transparent variety was selected, a repetition of the process three times gave results that left no doubt as to the nature of the action of the acid. Of the greyish-white variety of enstatite, after treatment for 20 hours with acid and 12 hours with potash, 9-414 per cent. dissolved, an analysis of which is given in column I. Of the grey tubular variety of enstatite, after treatment with acid for 16 hours, and with potash for a similar time, 7.779 per cent. dissolved, that gave on analysis numbers the approximate value of which is found in column II. Of the white variety, after the first treatment for 20 hours with acid, and subsequently with potash, 12.68 per cent. dissolved, the composition of which is given in column III. By a second treatment of the residual enstatite from this experiment, after 2 hours' trituration with acid for 30 hours and potash for 12 hours, 67.84 per cent. dissolved; and on subjecting the mineral to a third treatment in a similar way, 51.18 per cent. were dissolved in acid and potash. In the last of these experiments the ratio of the silica to the bases, neglecting the small amount of the former dissolved in the acid is as 58.4 to 42.0, that of an analysis of an enstatite being as 58-4 to 41.6. The solubility of the augite was determined by subjecting it to similar treatment with acid during 18 hours, and with potash for a like time, these reagents removing 7-384 per cent. of the mineral. Silicic acid Magnesia Lime Iron oxide, &c. Potash Lithia Soda found I. 5.408 2.367 II. III. 5.141 1.353 6.724 4.61 1.048 0.27 0.432 |