LXIX. Introduction to the study of mineralogy

M. Hauy
1809 The Philosophical Magazine  
Introduction to the Study of Mineralogy. 389 however, I think~ very unfbrtunate for My. Farey himself, that he either does not perceive, or as strangely indisposed to admit, the mo~t obvious cit~cts of water on the surface of tke earth. A decisive and very singular proof of this is given in that mo~t extraordinary and unphllosophical con-e|usion which he draws on the tormanon of valleys, and which unquestionably detracts, to an extent which he cannot be aware of, from his other acknowledged
more » ... er acknowledged merits as ar~ observing naturahst. The action ot water, in operating extensive changes on our earth, naturally dtvides itself into two distinct branches ; those changes which are effected bv streams of fresh water running over the surface, and those far more mighty exo torior and interior changes which the ocean itself has accomplished, during the submersion of our present oontinents. Were there any probability, Mr. Editor, that these cursory remarks of mine could merit a place in your most respectable repository of scientific knowledge, 1 would pursue the subject in two subsequent papers oa both of thesa branches; first by investigating, circumstantially, the formation of all valleys through which streams are now running, and afterwards adverting to the diversity and magnitude o[~ marine action. I am, sir, your most obedient humble servant, Jon~ CAnR. l?rinces Street, Manchester, May 1g, 1809. LXIX. Introduction to the Study of Mineralogy. By 21/I, HArdy -~ , I~ the motives which invite us to cultivate a natural seienee ,~ere founded merely upon the interest which certain productions of themselves inspire, and upon what appears at first sight attractive, zoology and botany would seem to have a prepcmderanee over mineralogy which would attract a g~eater number of admirers. * This is a translation of M. Hauy's Preliminary I~cour.se to his celebrate4 Work on Mineralogy. B b a Minerals~ Downloaded by [RMIT University Library] at 12:34 19 June 2016 890 Introduction to the Studff of M~neratog~. Minerals, for the most part being hid within the eavit~e~ of the earth, only come out of it in fragments, and bear tho marks of the iron instruments that have been employed to tear them from their beds: to the generality of mankind they are only crude masses, without character and withoul; appropriate definition, and appear as if intended solely to be appropriated to our wants. It has seldom been imagined that a distinct science could have been reared out of the subject, and that the naturalist should hold a place between the miner who extracts the treasures of Nature from the earth. and the artist who works them. Those however who, without dwelling upon first appearances, will consider minerals more closely, and with long continued attention, will easily perceive how much is to be gained by a more intimate acquaintance with their properties. Polyhedrie forms, the dinaensions and angles of which appear to have beea regulated by a scientific hand with the assistance of the compass ; the variatio~as which these forms, without ceasing to be regular, undergo in one and the same substance ; and the advantage of being able, by the help of ~ calculation and observation, to re-discover the traces of Pro, teus concealed under these metamorphoses ; i.ngenious experiments concurring with indicati~ans which speak at once t~ the eye, in order to develop the properties which escape him ; the principle of Archimede~ applied to the compadsort of weights under a given volume ; the refrangent power era. ployed in tracing a limit between bodies through which the image of eacla object appears simple, and those which present two to the astonished beholder; heat substituted for friction in order to produce electrical poles, in bodies the crystalline form of which, by particular modifications, indicates beforehand the positions of these poles; the magnetic needle making use of iron to disclose itself; various chemical agents presenting methods of dispelling doubts which other experiments had still left; the resources furnished by analysis for the formation of a method grounded upon the intimate knowledge of the objects which it embraces ; every thing ~:onspires to make mineralogy a science worthy Downloaded by [RMIT University Library] at 12:34 19 June 2016 ~2troduct;on to the Study of M{neralogy. 301 worthy of being received by minds naturally inclined to inquiries susceptible of precision and vigour, presenting ingenious combinations, and a collection of facts closely connected with each other. To such minds mineralogy presents itself under a new aspect. It is a picture which is embellished by the mere habit of seeing and studying it ; in which Nature exhibits herself, as she does every where else, under an aspeet which claims for the Creator the tribute of our homage and admiration. Mineralogy embraces a multitude of productions which human industry has not yet been able to mould to the wants or pleasures of life, without a certain study of their characters and of their nature, and without which art could not possibly clear the paths of science. From the earliest times the collection of these familiar productions had been subdivided into stones, salts~ bitumens, and metals. The methods of the mineralogist are, as it were, the first outlines of a picture. The working of metallic substances had ~hown several essential differences which distinguish them. Among ttle stones there have been composed numerous groupes under the names of marbles and gems, which, notwithstanding the disparity of the bodies which they served to connect with each other, were attempts at the formation of the genera which subdivide the classes. Certain properties, remarkable from their being elicited under certain circumstances only, have not escaped attention : the attraction exercised by amber when rubbed over light bodies, and the kind of sympathy between iron arid the magnet, which had been considered as a simple stone, have all been observed. Even the forma of crystals were not wholly unknown to the ancients ; that of rock crystal and of the diamond have been distinctly alluded to by Pliny *. The regular polyhedrons, which at present excite our admiration from their multitude ~nd diversity, were then also remarked as wonderful singularities. It is or~ly since the commeneemerlt of this century~ ho~- Hist. Nat. 1. xxxvli, c, 2 & 4. B b ,~ ever~ Downloaded by [RMIT University Library] at 12:34 19 June 2016 ~9~ tntroduct~on to the Study of Mineralogy. eveu that the learned have begun to submit the assembtx, g~ of inorganic bodies to methodical arrangements, and tba~ the term ~dneral kingdom has been adopted. .Among thn various systems which have successively appeared, soma of them, such as those of Linnmhs~ Watlerius, Daubenton, &e., employ in the determination of the species, gener~ orders and classes, certain characters which are, as it were~ presented to the naked eye ; such as those whi. h are derived Dora the form, textare, and transparency of the eolour~ ! or certain properties easily refilled, such as those of emitting light with steel~ effervescence with nitric acid, &e. Other systems, subjected to a more scientific progress, as traced by Cronstadt~ and followed by Bergman, Born, Kirwan~ &e., present the series of minerals classified according to their analyses ; so that, the species being determined by the identity of the component principles, the genera are formed of species which have a common'principle. The same method also serves in certain eases to connect together several g~ner~ in one andthe same ~rder: thus the neutral salts may be sub., divided into alkaline salts, earthy salts, and metallic sat% according to the kind of acid united to an alkali, an et/~'th~ or a metal. But when analysis failed in enabling mineralogists io form orders, its place was supplied by some chemic~| property common to all the genera of which each order wag the assemblage: and with respect to the classes, they were in the same way characterized after the manner in whiel~ the substances which composed them were modified in the various operations which spring from chemistry. It must not be thought~ however, that there was a line of separation clearly traced betwen the two modes of me" lho0.ic~.l distribution which we have mentioned. Chemist~ after having determined the series of the classes, orders, genera, and species, by the help of chemical properties, or of the results of analysis, could not descend ta the varietiesl except by employing external characters in order to distitr.. guish them from each other. Now, in a complete method, we are the less ont tied to dwell ,pon the species, as they are trequentlv ramified into se~eral subdivisioqs, the diffel'eaces of which~ much more striking than those bight and fugitive Downloaded by [RMIT University Library] at 12:34 19 June 2016 Introduction to the Stud~/ of Mineralogy. S95 fugitive shades which modify the varieties in botany, pre-sela~, from the different laws of Nature, orfrom the different ways in which she operates, results very distinct. In calcareous species, for example, the various crystalline forms, stalactites, rtlarbles, &e., are so many modifications of one and the same substance, which, without doubt, deserve to he separately observed and studied ; and if in all these we were not to see any thing but lime and carbonic aeid, it wouId be as if we contented' ourseIves with the inscription of a picture equally interesting by the assemblage and by lhe variety of its objeets. On the other hand~ it is evident that mineralogists have really profited to a certain point, by the results of chemistry, in order to form the distributions which ha~'e been designated by the term mineralogical methods : for without speaking here of the use which they have made of certain properties, such as effervescence with the acids, which is a true chemical property, they never could have been able, without the aid of analysis, to refer subsanees to their true classes. The carbonate of lead, commonly known as white lead, was regarded as a species foreign to the metals, and was probably arranged among the stones. In the Brisgaw s a few years ago, there was found a crystallized substance with small incrusted laminae, and of a white eolour : mineralogists had alternately regarded, it as a zeolit% and as a ponderous spar. The analysis of Pelletier~ h9wever~ assigned its true plaee~ as being among the ores of zin% by the namo of calamine. Chenfistry has therefore been, at least tacitly, lhe guide 0f mineralogists in the determination of species; and the formation of the genera is really the point at which systems in every respect begin to diverge. In those of the mineralogistsj the species which compose one and the same genus are connected with each other by a eharaeter derived from some quality which is common to them, or by several characters so combined that their asvemblage is considered as belonging only to the collection of the species in question. The genera adopted by chemists have their foundation in analysis itself: they depend, as we have Downloaded by [RMIT University Library] at 12:34 19 June 2016 ~94 Introductlon to the Studff of I~neralogg. have said, upon the existence of a principle common to the ~iifferent kinds, the distinction of which afterwards bears ~pon the principles which are peculiar to them. We see from that precedes, that chemistry and mine, ralogy necessarily concur to the formation of a rhethod~ whatev'er it may be, which has for its object the classification of inorganic bodies i that it belongs to chemistry to lay the first foundations of the method by the determinatinn of the species ; and that the difference depends upon what is contributed by each to the co.struction of the edifice which is raised upon that basis. I shall soon detail the principles which seem to me to conduce to the most advantageous application of this kind of alliance, On the other hand, natural philosophy unites with the-, mistry in order to furnish mineralogy with distinctive cha-~'acter% me more advantageo'us from their diving to the very bottom of substances, and they. are much less vari0hle than those of which we judge only with respect to the manner irt which they strike our senses. Experiments equally simple ~md easy seem to give us new organs, in order to penetrate to the most intimate properties of a substance : and we may answer those who think that mineralogy is sufficient for its own wants~ without intermixing with foreign substances, t~hat in operations so elementary, and requiring so small aa ~xpense, we see neither the naturalist nor the chemist properly so called, but the mineralogist alone~ interrogating ~ature in amore urgent and more fortunate manner ~, Geometry, in its turn, has direct and necessary relations with mineralogy, by the description of crystalline forms~ ~tnd still more by its numerous applications to the structure of crystals~ whichj of itselfz i~ only the result of a natural • Although this simple indication of chemical find physical propertle~ be sufficient for fulfilling our principal object, we have thought it right to add the explanation of these properties, and tkus tcdabour for men more partieu. l#rly versant in the sciences by which mineralogy may be extricated from th~ labyrinth of phrases purely descriptive, and be raised to the rank of the true ,tie,aces, which aggrandize their object by ascending to the laws to which they are subjected. They will of course do us a service, if they do not con-, fne us to the results of solitary'experiments, but, on the contrary, proceed to show their connection with the causes upon which they depend. geometry, Downloaded by [RMIT University Library] at 12:34 19 June 2016 Introduction to the Study of Mineralogy. 39~ geometry, subjec ed ~o t'artieu ar rules, and by which each solid has it, ~gure determined by the combination of an infinity of other small solids, which are like the elements of the first. A hasty glance at crystals will obtain for them the appellation of pure lusus naturce ; which is only an elegant way of confessing our ignorance, A closer examination unfolds to us ~he laws of arrangement in them, by the aid of which calculation represents and unites to each other the results observed i laws so variable, and at the same time so precise and regular ; simple in the extreme, yet displaying the utmost fertility. The theory which has served to develop these laws, rests entirely upon a fact the existence of which had been hitherto rather presumed than demonstrated. It consists in this, that these small solids, which are the elements of crystals, and which I call their integrant ~nolecules, have, in all those which belong to one and the same species of mineral, one invariable form, the faefs of which are in tile direction of the natural joinings indicated by the mechanical division of these crystals, and of which the respective angles and dimensions are given by calculation combined with observation. Besides, the integrant molecules relative to different species also have diversities among them more or less remarkable, except in a very few cases where their forms have characters of regularity, whence resuh, as it were, points of contact between certain species. It follows from this, that the determination of the integrant molecules should have a great influence over that of the species ; an d this consideration has led me more than once, either to subdivide into several species a groupe which, in the ancient methods, form only one, or to refer and re-unite the scattered members of a single species, of which several distinct spe., eies had been made. Some of these separations and reunions, made at a time when analysis had not yet unveiled the true nature of the substances which were the object of it, are now confirmed by chemical results ; and I shall even venture to say, that upon the hypothesis that no mineral substance had been as yet decomposed, we might, by a continued investigation of the integrant moleeules~ form assort.. llletlts~ Downloaded by [RMIT University Library] at 12:34 19 June 2016 ~9~ Introduction ta the Study of Mineralogy.
doi:10.1080/14786440908562889 fatcat:tz5tja2trfe77n6dl362oozpsu