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NATURE 



[Nov. 29, 1888 



But is it necessary that the number of people in this country 

 with a lively interest in mineralogy should remain so small ? 

 We have only to look abroad to see at once that the cause of 

 this smallness of number is not inherent in the subject itself. In 

 Germany, for instance, everyone — of course, with here and 

 there a conspicuous exception — seems to be either a Professor of 

 Mineralogy or a student of it. Periodical publications, at once 

 voluminous and teeming with valuable results of scientific work, 

 are there maintained. Somewhat more than a century ago, 

 the study of minerals was everywhere popular, and received its 

 share of attention from the cultured classes. Students thronged 

 to Freiberg from all parts of the world to hang on Werner's 

 lips. 



There is one reason for this decline of general interest in 

 mineralogy which I may mention in passing. In the good old 

 days minerals were named and classified by help of simple ex- 

 ternal characters, and the facts of the science could be easily 

 grasped without much preliminary training. Since then, the 

 invention of crystallography and of the atomic theory, and the 

 discoveries made in physical optics, have brought about a vast 

 change in the treatment of the subject, and the mineralogy of 

 to-day is even in its elements beyond the range of ordinary 

 mortals. The pages of its text-books are sprinkled with 

 wonderful formula; designed by perverse chemists, and with 

 unpronounceable hieroglyphics maliciously invented by cruel 

 crystallographers. 



But the chief reason for the decline of mineralogical study in 

 our own country is that mineralogy has been almost completely 

 excluded from our educational system. In the older Universities, 

 it is true, mineralogy has been long represented by Professors, 

 but, until lately at least, it has been allowed scarcely any weight 

 in the examinations for a degree. The study of other branches 

 of science has been encouraged, while that of mineralogy has 

 been neglected and forgotten. One of the evils of the examina- 

 tion system is that all the available energy of our youth is con- 

 centrated wholly on subjects upon which stress is laid by a not 

 omniscient Examining Board ; most students, too, must almost 

 necessarily take up subjects in which there is an opportunity of 

 showing their comparative ability, and by a knowledge of which 

 there is reasonable prospect of being able to gain a future 

 livelihood. 



Taught only as a subordinate and unimportant subject at the 

 Universities, and not taught at all outside, pure mineralogy has 

 been in great danger of becoming extinct in this country : a few 

 years ago the capsizing of a coach or the bursting of a balloon 

 might have been the end, and the British Professor or student 

 of pure mineralogy have laecome a mere tradition. 



The discovery of the transparency of thin rock-sections, and 

 the important conclusions which may be arrived at from their 

 microscopical examination, have now turned attention to minera- 

 logy once more, and it seems likely that the knowledge of 

 mineral characters requisite for petrographical work may at last 

 lead to our mineralogical renaissance. Owing chiefly to the 

 patience and perseverance of Prof. Lewis, there is now a certain 

 amount of encouragement to mineralogical study at Cambridge ; 

 and if the renaissance is to be brought about, the example of 

 Cambridge must be followed by the other Universities, and 

 mineralogy be assigned a higher place in the examinational 

 system. 



Minerals are omnipresent. Is it unreasonable to ask that 

 everyone should be taught their simple characters, and be shown 

 how to recognize such minerals as are met with at every turn ? 

 The teaching would improve the capacity for observation, and 

 give fresh irtterest to many a pleasant ramble— through the 

 workings of a mine. And is not Prof. Ruskin in the right when 

 he claims that a knowledge of the minerals, conveniently grouped 

 as precious and ornamental, should form a part of every gentle 

 education ? More especially ought we not to insist upon such 

 elementary teaching for the numerous officials sent out by the 

 nation to the less explored regions of the world ? 



In the higher teaching of mineralogy, difficulties present 

 themselves, but they might easily be lessened by division of 

 labour ; a preliminary training in the elements of mathematics, 

 physics, chemistry, and crystallography being absolutely necessary 

 to the manufacture of a mineralogist. The teaching of crystallo- 

 graphy is generally relegated to the Professor of Mineralogy, 

 and the subject regarded as a mineralogical difficulty ; but this 

 ought not to be the case. It is true that a mineralogist was the 

 first to discover a relationship between the various crystallized 

 . forms of the same substance, and thus to institute a crystallo- 



graphic science, which has since been found indispensable in 

 mineralogical study. It is true'that the mineralogist has been 

 the originator of every advance in crystallographic knowledge. 

 It is true that the mineralogist has in minerals ready-made 

 crystallizations, which in their excellence and variety of form can 

 rarely be imitated in the laborator)'. But it is no more the pro- 

 vince of a mineralogist to teach crystallography than it is to teach 

 chemistry or the use of a delicate balance. He does teach it 

 indeed, but that is merely because his pupils reach him im- 

 perfectly trained for the pursuance of his own subject. 



Crystallography should be taught as a special subject ; and a 

 knowledge of it should be required not only of the mineralogist 

 but of the chemist, and even of the physicist. Hitherto, at least, 

 the chemists of this country have been too content cither to leave 

 the crystalline forms of their artificial products undetermined, or to 

 impose the task of their determination on the already sufficiently 

 occupied mineralogist. It seems obvious that in a satisfactory 

 system of education every chemist should be taught how to 

 measure and describe the crystalline characters of the products 

 which it is his fate to call into existence. On various occasions 

 expression has been given to this view, but the only chemist who 

 has yet seen his way to act upon it is Prof. Henry Armstrong, 

 who, I am happy to say, has introduced the subject into the 

 educational course of the City and Guilds Technical Institute. 

 I trust that before another generation passes away his excellent 

 example will be followed throughout the country. A knowled;je 

 of the elements of crystallography, including the mechanics of 

 crystal measurement, ought to be made a sine qua non for a degree 

 in chemistry at every University. 



The measurement of the angles of a crystal, the determination 

 of its symmetry, and the calculation of its form, are infinitely 

 less difficult than is generally imagined : given a knowledge of 

 elementary mathematics and the caretul use of measuring instru- 

 ments, the processe; are in general extremely simple. The 

 complexity of cry-tallographic calculation is only apparent, and 

 is due to the existence of text-books : they are generally worse 

 than useless. A voluminous work on crystal-calculation is usually 

 an attempt to provide formulae which shall enable a student to 

 solve every possible problem by rule of thumb, without his 

 needing to have the faintest idea of what he is really doing. 

 Practically, anyone familiar with the processes of trigonometry 

 can deduce from first principles the formula required for each 

 special case as it occurs in less time than he can discover the ru|e 

 in the ponderous tome invented for his mystification. 



I am, of course, far from asserting that the teaching of crystallo- 

 graphy presents no difficulties at all : what I do wish to insist 

 upon i-; that the kind of crystaJlographic knowledge requisite for 

 the chemist in his own work is such that it may fairly be 

 demanded of every one of them : the higher flights may be 

 abandoned to the specialist. 



At the present time, when Professors of Crystallography are 

 not yet called into existence, there is one step which ought to be 

 at once taken, and which would maka mineralogy more possible 

 eventually to a large number of our students. Every student of 

 practical physics is taught how to measure with a reflecting 

 goniometer the angles of an artificial prism : he should further 

 be taught the measurement of the angles of a simple crystal, and 

 the deduction of its symmetry. In his optical studies especially, 

 such a practical knowledge of crystalline symmetry would be a 

 great help to him. The reflecting goniometer in one of the forms 

 used for crystallographic work might well be an instrument in use 

 in every physical laboratory, and would subserve many a useful 

 purpose. As soon as every physicist is taught how to determine 

 the angles and symmetry of a simple crystal, and every 

 chemist is further enabled to define the crystalline forms of his 

 artificial products, we shall have a large army of students for 

 whom the transition to mineralogical work will be easy ; then, 

 and not till then, can we hope for any useful increase in the 

 number of the members of this Society ; then, and not till then, 

 can we hope that our country will in its study of mineralogy take 

 its proper place among the nations of the earth. 



One more point I may mention. Until a few years ago there 

 were two distinct Societies, a Mineralogical and Crystallological : 

 they had objects far from identical, and in a more perfect 

 world might have flourished side by side. The fusion of the two 

 Societies without any extension of the title of the Mineralogical 

 has had for its effect that we cannot satisfactorily demand what 

 the Crystallological could— namely, the support of the organic 

 chemist ; and although it was understood at the time of the 

 fusion that papers on the crystallization of artificial products, 



