Obrazy na stronie

known, and the weight of equal volumes, the expansion I have tried to collect the evidence, in order that we might could obviously be readily determined.

know what data were really available, and where the worst The coefficient of cubical expansion for ° C. from gaps lay. The discrepancies which sometimes come to o° C. to the point of change-526° C.-was found to light are amazing. Take a large number of specific gravity be :

determinations for any given compound, and see how dis0'0000344706.

cordant they are. The values will range through wide At 126° C., during the change from the red octahedral

limits, so that it is often imposible to say which one out of to the yellow prismatic condition, the body increased in

several is the best. These variations may be due partly bulk to the extent of:

to bad work, and partly to unrecognised differences in 0'00720407

chemical constitution. Some of them are so peculiar that The coefficient of cubical expansion for r° C. from

they can hardly be expiained, except upon the hypothesis 1 26° C., after the change, h, to the melting point 200° C.,

that they spring from some undiscovered allotropy or

isomerism. The metallic iodides furnish some good illuswas0.0001002953.

trations of this idea. The well-known properties of

mercuric iodide, Rodwell's experiments upon silver iodide, Thus, if we suppose a molten mass of the iodide of

and Cooke's researches into antimony iodide are suffi. mercury to be cooling down from 200° C. to o° C., the

ciently suggestive. When, therefore, we meet with disfollowing would be the volumes under the conditions,

cordant specific gravity determinations among other indicated :

iodides, we may reasonably suppose that one experimenter Vol. at 200° C. of the liquid mass .. .. = I •1191147 has dealt with one allotrope, and another with another, , solid mass .. .. = I '0190453

both unconscious of any existing differences. But how. 126° C. (yellow prismatic condition) = 1 '0115378 ever this may be, the discordance of so many data, not

(red octahedral condition) - I '0043337 unly among specific gravity measurements, but in all ° C. .. .. .. .. .. .. .. = I '0000000

other series of determinations, serves to show how little

we really know, how much work remains to be done According to Schiff the specific gravity of the octahe. dral iodide is 5'91 ; while Karsten makes it 6.2009, and

freshly, and how much ought to be done over again. Of Boullay 6-320.

all the figures upon which we now rely for the solution of

these grander problems, at least three-fourths should be Two distinct specimens with which we worked gave

scrupulously re-determined ; and even after that had been respectively,

done our material would still be woefully insufficient. The (1). 6 •3004

kind of work we need may be well illustrated by the (2). 6 .2941

classical labours of Stas upon the atomic weights, and The specific gravity of the fused iodide was found by the immortal researches of Regnault into the physical the method before described to be

properties of vapours. Such work as this will give im. 5° 2865.

perishable foundations for exact science, strong enough Thus the specific gravities corresponding to the five

and broad enough to sustain the most stately edifice which marked conditions shown in the curve table are as fol.

the human intellect can rear. lows:

To my mind, the investigation of this sort most imme.

diately needed is the accurate determination of all the Sp. gr. at oo C. .. ..

... = 6 '297 physical constants for all the so-called elements. This 126° C. (octahedral condition).. = 6.276

would supply evidence direaly related to all three of the , (prismatic condition) .. = 6 .225

great problems. We might thus learn something about

the nature of the elements themselves, and how far the O liquid .. .. .. .. = 5 .286 transformations of energy due to chemical action de.

pended upon their individual characters; we should also be put in some position to predict the properties of com.

pounds. In many important lines of research, science THE CULTIVATION OF CHEMISTRY..

would then replace speculation, and the imagination By F. W. CLARKE, S.B.,

could still find ample fields in which to exert its powers. Professor of Chemistry in the University of Cincinnati. As yet such work as this has not been done for even one

of the sixty-five or sixty-six elements known. Take iron, (Concluded from p.si).

for example, the most important of the metals, one

which has been the subject of numberless practical re. ALTHOUGH the foregoing statements relate specifically to searches,-and we as yet know it in these more purely the first of the three great problems, similar principles scientific relations barely on the surface. Not a single apply to the second. If we are to determine what general series of physical constants has yet been thoroughly delaws connect the properties of compounds with those of termined with regard to it, notwithstanding the light that the elements contained in them, we must first secure a such investigations might shed upon important industrial large mass of well-established data to work from. For a problems. We know a little here and a little there; a bit very large number of substances, such constants as density, about its thermal properties and another bit about its crystalline form, melting and boiling point, thermal con electrical properties, but nothing systematically and well. dudivity, specific and latent heat, co-efficient of expan. As for gold, silver, copper, and mercury, rather more is sion, index of refraction, electrical resistance, and so on, known; but even with these elements not a tenth of what ought to be rigorously ascertained. With such accurate ought to be done has really been accomplished. data, we may hope to reach the desired laws; without The reason for such incompleteness in chemistry is suf. them we can see but a little way. Moreover, every con. ficiently evident. Indeed I have already hinted at it. stant should be determined in a much more thorough man. The labour of investigation hitherto has fallen chiefly ner than any have been determined hitherto. Every upon the shoulders of volunteers, who have worked in measurement should be repeated many times, and under all great measure independently of each other, every man attainable conditions; otherwise the work would be ma. following his own particular bent. Part of the work has nifestly incomplete.

been done by teachers, in their odd moments of freedom Fragmentary researches of this kind have already been from the drudgery of instruction; other portions were carried out in great number; but how?. In some directions carried out by inventors, or by manufacturers with refer

ence to special industrial questions. There has been little • Address before the Permanent Sub-section of Chemistry of the American Association tor the Advancement of Science, at the

co-operation, and no organisation of efforts. The one SA Louio Meeting, August, 1878.

class of investigators has sought for the glory which bril

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6 •179



Cultivation of Chemistry.

CHEMICAL Nows, (February 7, 1879.

liant discoveries bring; the other has laboured to secure that of teaching, and probably as much leisure for himsel pecuniary rewards. Thus has our pure science grown and his own ideas as before. Indeed, to carry out the unsystematically, and our applied science has been im. latter his opportunities would be vastly improved. perfectly applied. The two depend on each other; and Who can doubt that such a laboratory would benefit the more complete pure science can be made, the simpler science ? To have important data systematically deter. and more beneficent will its applications become.

mined, with every conceivable precaution and the best What chemistry needs, then, is combined effort upon appliances, would certainly be worth while. Every industry some general plan. There must be a body of trained involving applications of physics or chemistry would be workers under an efficient head, who shall mark out some aided. The special problems of the ironmaster might not of the lines for investigation to follow. Such a co. be touched, and yet evidence would be discovered which operation can hardly be brought about under existing cir- should enable him to solve them much mcre easily and cumstances and with present facilities, since as a matter of certainly than before. Precision would be gained everycourse every scientific man prefers to work independently, where; in facts, in methods, and in appliances; theories and to shape his researches for himself. Something may would rest on more solid foundations; the intellect would be done, perhaps, by those college professors who are find new food for thought. The work done might seem at fortunate enough to have a considerable number of ad. first sight to be of the hardest, driest, and most practical vanced students to assist them; but work carried forward character; and yet there would be within it more than under such conditions can scarcely amount to more than utility. We cannot deepen our knowledge of the real a clearing of the ground. Still such pioneer labour is not without at the same time broadening our insight into the to be despised. It marks out many useful pathways for ideal. The more we know, the vaster the unknown seems us, and shows where the chief difficulties are to be en. to us. The better we know, the more truly do we recog. countered. The one great method, however, by which the nise the imperfe&ions of our knowledge. We climb cach desired ends may be attained is to be found in the esta. | mountain only to see a bluer, higher, grander summit far blishment of endowed laboratories devoted to pure re. beyond. search. With regard to laboratories of this kind much Can this conception of a laboratory for pure research has been written, both for and against. From two dis- be realised ? I believe it can. Physics and chemistry tinct points of view has the subject been treated. One have created millions upon millions of wealth; they have set of writers has opposed the idea of endowing research, helped to bring distant countries nearer together, they upon what appear to me to be wholly fallacious grounds have benefited every human being within the limits of They have urged that the payment of salaries to scien. civilisation. In every country of the civilised world there tific men, either as a reward for past services or as a are many rich men who owe their wealth to the applica. means of encouraging future work, would probably result tions of these sciences. In our own country especially, in the foundation of sinecures in which pretentious idlers we find such men ready and often anxious to give. Every might find an excuse for doing nothing. A man could day we hear of large bequests for public purposes; of easily pretend to make investigations, and in reality only gifts to colleges, libraries, observatories, and museums; to fritter away his time in a sort of elegant leisure. No en hospitals, asylums, and churches; to the poor and to the dowment would render brilliant discoveries certain, so heathen. Surely some of the wealth which our science that fruitlessness might find ready apologies. This is a has rendered possible ought to come back a little more somewhat extreme statement of the case, though not a directly for her benefit. There must be men who would wholly unjust one. Such forebodings as these might be give liberally to her purposes if they only knew of her realised, although it does not to me seem probable that needs. Can we not do something towards making our the men who now labour so earnestly and assiduously for wants known ? Are we not able to present a strong case the love of knowledge would accomplish any less because in our own favour? Might we not by some combined of greater encouragement. Still an endowment which effort at least make a beginning, and secure a fund, which afforded large salaries for no regular, specific duties, might should serve as a fulcrum for our future exertions? Let in some cases work mischief. The true man of science a nucleus once be established near some large university, would hardly advise even a possible wasting of means. or under the control of such an institution as the Smith.

The idea of an endowed laboratory for research is of a sonian, and it cannot fail to grow. If the first organised very different kind. It proposes an institution in which laboratory, for such work as I propose, could be founded salaries shall be paid for work of a definite, prescribed in this country, it would soon be recognised as a nationa character. Men would not be employed in it to make glory and a benefactor of the whole human race. I throw showy discoveries, although these might be rendered inci. out these suggestions merely as suggestions, with the dentally possible. The laboratory would, in short, be a hope that some means may speedily be found which shall place wherein the fundamental data of chemistry and lead us to the much desired end. physics should be accurately established, without more In Europe the needs of science are often liberally pro. than casual reference to particular industrial questions or vided for by Government. The scientific institutions of to theories. In it a body of trained specialists would co Germany, for example, owe their existence and support operate upon such researches as I have suggested ; they chiefly to funds drawn from the public treasury. This would fix some of the foundation stones of science; they policy I believe to be wise and proper, although it might would combine their strength upon those tasks which are not be judicious to urge it strongly here. With us, the too large and too arduous for individuals to undertake. proposal to establish a purely scientific institution, upon Just as an astronomer makes an exact map of a given moneys raised by general taxation, would undoubtedly be zone in the heavens, observing the position of each star seriously opposed. The public importance of the measure over and over again; so the workers in this laboratory would be obscured by a clamour about economy, and would undertake repeatedly those delicate measurements upon the wickedness of expending the means of the many which physical science so much needs. The physical for the benefit of the scientific few. Much of this oppo. properties of substances could be exactly determined ;sition would be foolish, although at the same time effec. methods of measurement could be tested and improved ; tive. Still, granting that it might be unwise to ask the apparatus too expensive for individuals to own might be National Government to establish a laboratory for reconstructed and employed; the quantitative relations of search, there is another kind of laboratory which it might the several forces could be accurately ascertained. One build, equip, and organise, with unquestionable propriety. great problem at a time might be taken up, and the energy All the time the General Government finds it necessary of the whole body of workers concentrated upon it. to employ chemists for special expert work. For the Under ordinary existing circumstances a scientific man Bureau of Engraving and Printing investigations are teaches several hours a day, and after that he labours at made with reference to the inks and paper used in the research. Here he would have a different routine from manufacture of notes and bonds. Questions are con.


CHEMICAL News, 1 The Seven Fundamental Types of Organic Chemistry.

February 7, 1879.7 tinually arising in conneaion with the custom houses, Science, I may be permitted to broach one more subject which can only be settled by the testimony of a reliable which I believe to be of some importance Year after chemist. Frequently the Examiners of Patents would be year the researches of American chemists are steadily much aided in their decisions if they had laboratory facili- | increasing in number, extent, and value. Work like that ties at their command. The War and Navy departments of Gibbs, Cooke, Smith, Mallet, Remsen, Jackson, and a are continually needing work done, it may be in the dozen others who might be named, is certainly work of examination of supplies, in testing metals, or in experi- which we may reasonably feel proud. But how is all this ments upon explosives. For the Lighthouse Board there material published ? A little of it in the American are oils to be tested, and for the Geological Surveys there Fournal of Science and Arts; a part in certain foreign are rocks and minerals to be analysed: As for the Agri- | periodicals; another portion in several local transactions, cultural Department, it already has a small laboratory, l as for example the Proceedings of the American Academy. and there is another connected with the Army Medical In short, the work is widely scattered, and some of it is Museum. These examples do not by any means complete effectually buried beyond the reach of a majority of our the list; they only serve to show how great an amount of fellow chemists. We need, I believe, in this country, á scientific labour the National Government is obliged good chemical journal which shall fairly represent the annually to employ. The work is now done in a scattered work that America is doing for chemistry. A journal in way, often with imperfect appliances, and much less which every chemical research published in the United thoroughly than is desirable. The question I now raise States should find a place, either in full or in abstract, is this: Would it not be eminently proper for the Govern would certainly stimulate investigation among us, and ment to establish a first-class chemical and physical send all over the world a truer estimate of our scientific laboratory, in which all of its work in these departments standing. We might have for our organ a chemical should be done by an adequate body of scientific men, periodical equal to any in the world, and I sincerely hope provided with the best materials and apparatus ? Would that we may not have to wait long for its establishment. not this be a measure of true public economy? Could Where or by whom it should be edited and published is not more and better work be done for a given sum of a question I will not attempt to raise ; suffice it to say money than is done now ? Tome it seems that the plan that it ought to be controlled by no local clique, and is decidedly practical, and that Congress might by judi- managed in no Pharisaical spirit. It should be broad cious pressure be induced to carry it out. Of course the | enough not to fear novelty, and courageous enough to measure is open to the usual political objections. It reject trash; two qualifications more easily stated than might enable inefficient men to get responsible positions found. I throw out these suggestions, hoping that they through political influence; and there would be a possible may take root somewhere, and that without much delay. danger that corruption should secure another foothold Even though we ourselves may lack the power to carry where it is already too firmly lodged. This objection I them out, our recognition of their importance may lead do not believe to be sound. At present experts may be to action elsewere. If we in our gatherings can point employed through political favour, while the country at out good pathways, others with richer means may be large knows nothing of what is going on. In a national | induced to follow them. Our united counsels and comlaboratory the appointments would be conspicuous, and bined efforts may achieve results where, working sepamismanagement would at once be recognised. There is rately, we should fail. an argument from analogy which may be even stronger than this. Whatever weakness our public officers in general may have exhibited, our scientific service has always been remarkably able and strong. If the proposed THE SEVEN FUNDAMENTAL TYPES OF laboratory could be made as efficient as the Naval Obser

ORGANIC CHEMISTRY, vatory, the Coast Survey, or the Army Medical Museum ; if it could secure as thorough men as these have secured, AS VIEWED AND INTERPRETED FROM THE STANDPOINT the objections just urged would disappear. The nation

OF THE “ TYPO-NUCLEUS” THEORY, must get the work done somehow, and would it not be best done in the manner I propose ?

By OTTO RICHTER, Ph.D. Such a laboratory as this, organised at first for the

(Concluded from p. 48.) merely practical work of the Government, might in course of time widen its scope a little. The National Observa. tory, established originally for the purposes of the Navy In passing on to consider the second stage of the process, Department, has been able to do much for science beyond we may suppose that, by a species of lateral movement on its purely routine labours. The expenditure of public the part of the newly formed subjunct nucleus away from money for eclipse and transit expeditions, in furnishing the outer or inner conjunct chamber towards the outer the means for work like that of Newcomb and Hall, has or inner subjunct chamber, that molecule, while it remains been for the interests of abstract science ; but I doubt still firmly attached to the principal nucleus by means of whether any intelligent citizen has ever begrudged aits appropriate number of thermal bonds, will at length dollar of it. The nation has been ennobled by such re. arrive at the particular point whence it may be brought to searches, even though no material benefits should ever take up a fixed and well-defined position within the cor. spring from them. So with a national laboratory. At responding subjunct chamber, a position which it will unfirst its work would be only a technical routine ; but doubtedly continue to maintain after the whole system sooner or later this would necessarily develop into some has returned from the nascent state of unstable equilibrium thing more. The Government investigations could not into the quiescent state of stable equilibrium. It is be carried on for ever by imperfect methods; and accord. scarcely necessary to add that at the close of this second ingly better methods would have to be devised. What. stage of the process no substitutional action has as yet ever researches tended towards improving the work done taken place, the affected molecule having simply undergone for the nation would, of course, be properly carried out that particular preparatury treatment which befits it for in a national laboratory. Thus an institution, established the exercise of its newly acquired chemical duties and for pra&ical purposes at public expense, could at the same functions. Finally, as regards the third and last stage of time benefit the public service, and advance the interests the process which, in the majority)i cases, involves the of science. The cost would be justified ver and over presence and co-operation of two contending molecules, again in a purely material way, so that the question of its chief characteristic feature consists in the successive the usefulness of the laboratory could never be seriousl interchange of one or more thermal bonds with simultaraised.

neous transfer of their respective subjuncts from one As we are gathered together for the Advancement of' principal nucleus to the other. :

I CRYMICAL NEW 60 The Seven Fundamental Types of Organic Chemistry. { Cheroes, Nisay

February, 7 1879. Reserving the fuller discussion of this important subject tive and fascinating subject, in order to examine into the for a future communication, I shall here content myself last remaining set of fundamental types which I have with a brief enunciation of the general law which I hold represented as standing under the immediate control of to preside over this particular order of chemical pheno- the principle of polarity or chemical principle. This mena. But before doing so it will be necessary for me to principle rests upon the hyphothesis that in their nascent pass a few observations on the proper meaning and use of or chemically active state of existence every species of ihe technical terms" Multivalence" and "Quantivalence," molecules, from the simplest to the most complex, is terms which, the reader will not fail to remember, have capable of being transiently thrown into a state of electronow and then formed the subject of very animated but far chemical polarity. This new kind of agency is supposed from satisfactory controversies in our leading journals and to attain its maximum of force in the direction of a straight debating societies.

line intersecting the molecule at right angles to its opera. In pondering this question from the novel and more tive axis, and coinciding with the polar axis of that moleelevated standpoint of my “ Typo-nucleus” theory, I was cule; while in a plane at right angles to that axis, which not slow in perceivir.g that a fatal error had been committed coincides therefore with the equatorial plane of that mole. by either side of combatants in not sufficiently discrimina. cule, the said agency is supposed to attain its minimum. 'ting between the absolute substitutional power and capa. This hypothesis, strange and mysterious though it may city of a principal nucleus pure and simple and the relative appear at first sight, leads at once to the consideration substitutional power and capacity of that same nucleus of two possible alternatives. In the first alternative, any when associated with a variable number and quality of two conflicting molecules may be represented as conouter or inner conjunct molecules.

fronting each other in such a way that the polar axis of From an extensive series of researches in this direction the one becomes opposed to the polar axis of the other ; I have arrived at the interesting and all-important conclu. | while in the second alternative they may be represented sion that in the former case the said power and capacity | as confronting each other in such a way that the polar is always measured and expressed by one single thermal axis of the one becomes opposed to the equatorial plane bond only, because it forms the only connecting link be. of the other. tween the two semi-nuclei into which the original mole. | Applying this hypothesis to the direct chemical union cule has been made to resolve itself, while in the latter of two or more principal nuclei with each other, I have case the said power and capacity is always measured and arrived at the conclusion that all the members of the outer expressed by the variable number and quality of those adjunct type which embrace the true polyatomic alcohols outer or inner conjunct molecules which have passed from and their numerous basic and acid derivatives owe their the original state of conjunds into the typically altered origin and formation to the first of these alternatives, and, state of subjuncts. Now, in my mode of viewing the | again, that all the members of the inner adjuna type term, “ Multivalence is correctly emloyed whenever we which embrace the pseudo-polyatomic alcohols and their wish to indicate the aggregate number of chemically numerous basic and acid derivatives owe their origin and similar or dissimilar conjunct molecules that have entered formation to the second of these alternatives. It deserves into direct chemical union with a given principal nucleus, special notice also that the typical differences arising while the term “ Quantivalence" is correctly employed from the circumstance that the chief component groups of whenever we wish to indicate the number of subjunct the former class of molecules are co-ordinately, because molecules into which the whole, or a certain part only, of axially and axially, united, while those of the latter associated conjuna molecules have been successively con. class of molecules are subordinately, because axially and verted, it being distinctly understood that such conversion equatorially, united, are of such a nature as materially to is invariably accompanied by the simultaneous formation interfere with the general law of molecular collocation of a corresponding number of as many thermal bonds as and arrangement. From a host of well-established exare lawsully required to serve as connecting links between perimental facts and observations I have it in my power the principal nucleus and its evolved subjuncts.

to prove that, while the general law continues to exercise The preceding statements and explanations will, I trust, an absolute control over all the members of the outer enable the reader to grasp the full scientific bearing and adjunct type, it is no longer applicable to the members of significance of the remarkable law above referred to, and the inner adjunct type, where its frequent infringement which may be briefly enunciated as follows:- The substi. is apt to give rise to a great number and variety of isotutional power and capacity of a given principal nucleus, meric compounds, the formation of which seems chiefly after it has entered into direct chemical union with a to depend upon the precise order in which certain organic given number of outer or inner conjunct molecules is a and inorganic bases or acids are made to unite with that variable and fluctuating quantity, which is measured and class of molecules. expressed pro tem. by the collective number of thermal! Having now submitted to the reader a brief and tolerably bonds emanating from that particular set of outer or inner complete general outline of the seven fundamental types conjunct molecules which have been made to pass from of chemistry as colle&ively exhibited and placed side by the original state of conjuncts into the typically altered side in our model molecule, I may yet be allowed, in state of subjunds."

drawing to a close, to give vent to a few appropriate It deserves to be borne in mind that the said power and remarks and sentiments. capacity is entirely independent of the chemical nature of It is my humble opinion-an opinion that is probably the element out of which the principal nucleus has been shared by the majority of unbiassed and more calmly moulded, for that element is found to contribute not one refleding chemists—that, in the course of its marvellously single unit to the sum total of the thermal bonds collec. rapid progress and development our science has at length tively attached thereto. We are thus driven to the un. arrived at that critical turning point where its votaries are expected but inevitable conclusion that the substitutional compelled to answer to themselves the question—"Is it power and capacity with which our modern speculators meet and desirable in the face of such an overwhelming are in the habit of crediting the principal nucleus does not mass of ever-accumulating facts that we should still go on reside therein at all, but may be said to exist in a kind of contenting ourselves with the adulterated and unpalatable latent state within the outer or inner conjunct molecules, compost of antiquated notions and untenable dogmas, until the conversion of the latter into the corresponding hallowed though they may be by the honoured memories subjuncts causes that power and capacity to become of so many deserving and illustrious experimentalists, and revealed under the form of interchangeable thermal bonds may it not be that our boasted knowledge and pretended which, as a variable and fluctuating quantity, are made to insight into nature's secrets is merely a gross delusion and range between the more or less circumscribed limits of a á snare, the natural result, in fact, of grave speculative well-defined maximum and minimum.

errors and prejudices, which must inevitably melt away It is now time for me to dismiss this singularly attrac. | under the genial rays of a more profound and enlightened News

The Graham Lecture. February 7, 1879.7 system of chemical philosophy ?" Already, if we may aniline without going through the violet; and taking as udge from certain highly interesting and invaluable con. startiog-point the theoretical and meritorious studies of tributions to spectroscopy with which Mr. Norman Prof A. Baeyer, Otto Fischer, in Munich, and Oscar Lockyer and others have recently regaled the chemical Docbner, in Berlin, it has been found possible to produce

profession, a new and unexpected light has suddenly been green direct from dimethyl-aniline, and even at a very low · brought to bear upon the all-important question whether price.

the chemical elements ought still to be regarded as simple. These direct greens are brought into the market under bodies in the ordinary sense of the word, or whether these the names of New Fast Green, Malachite Green, &c.,' and elements ought not rather to be regarded as more or less possess about the same chemical qualities, but the mode complex bodies that, under the dissociating influence of of manufacture and the attention paid to the same, cause temperature, may, like other truly compound substances, more or less a difference in brilliancy of shade and be brought to resolve themselves into molecules of lower yielding. It is, however, very easy to distinguish direct atomic weight, and presumably also of different chemical greens from methyl.greens through the simple fact that and physical properties, from their parent molecules. It wool, silk, or cotton, when dyed with direct greens, can is contended -- and I think rightly so--that these wonderful stand a very high degree of heat without the green colour spectroscopic discoveries are totally inexplicable on the turning into violet ; whilst stuff dyed with methyl-greens prevailing biatomic hypothesis. What other hypothesis turns violet when brought into contact with an iron exihen, I would ask the reader in all humility, remains for ceeding 120° of heat. our final adoption but that same polyatomic hypothesis The aforesaid theoretical mode of Otto Fischer, in which forms the theoretical basis of that very system of Munich, was published in the reports of the Berlin Chechemical philosophy I have been the first in expounding mical Society on August 11, 1877, under the title of and elaborating-a system, moreover, which, with respect “ Condensations Producte Tertiärer Aromatischer Basen." to the splitting up or condensation of chemically simple or Otto Fischer describes therein a new base, which he compound molecules, presents no difficulties whatsoever, I obtains by the reaction of dimethyl-aniline, chloride of while it possesses in these two opposite tendencies a ready zinc, and hydride of benzyl, and further states that and fertile source for the complete elucidation of many | oxidising the salts derived from his method led to the hitherto obscure and unintelligible chemical phenomena. production of a beautiful bluish green colour. With regard to the fundamental axiom which underlies my The exceedingly high price of the hydride of benzyl has whole chemical system, namely, that not only every species hitherto prevented the practical application of Fischer's of chemically elementary molecules, but likewise every most interesting discovery. Now, however, this material variety of chemically compound molecules, as embraced is produced at a price which renders its practical use quite under the generic term " Model Molecule," aie made to possible. exhibit relatively to the thiee conjugate axes of space the The process of manufacturing malachite-green is based most perfect symmetry of form and atomic arrangement, upon the theoretical studies of Oscar Doebner, pub. I have yet to observe that our model molecule with its lished in the reports of the Berlin Chemical Society, seven-chamber system, in order to satisfy the aforesaid | May 27, 1878. fundamental law, requires to be doubled; in other words, Doebner proves in his report that green can be ob. that such molecules require to be united into one by tained direct from dimethyl-aniline, chloride of zinc, and joining them together with their inner adjunct chambers. trichloride of benzol.

t will at once be seen that, under this new aspect, the Besides the before-mentioned system of producing direct symmetry of the whole system is rendered perfect; and I greens through the medium of hydride of benzyl, there are may now state, in addition, that this re-duplication of our other methods by which the same can be obtained : for model molecule will not oblige me to alter my customary instance, the product of the reaction of dimethyl-aniline, mode of notation, if it is taken for granted that any mole. chloride of zinc, and dichloride of benzoyl, submitted to cular changes in the right moiety of our model molecule oxidation, gives a very beautiful and cheap green. are invariably and simultaneously accompanied by similar From the preceding statement it is obvious that different molecular changes in the left moiety.

methods of manufacturing direct green exist. In now taking final leave of my subject, I may yet be permitted to express an anxious hope that the arduous but imperatively necessary task of a thorough revision and reconstru&ion of the groundwork of theoretical chemistry,

THE GRAHAM LECTURE, a task initiated by me a number of years ago, and evidently desired and prayed for by that small but rapidly increasing band of chemical practitioners whose reasoning powers

Thy Philosophical Society of Glasgow have determined have not as yet been crippled and paralysed under the to institute a triennial lecture in memory of the late Prof. withering influence of a perverse and unyielding dogma. Graham, Master of the Mint, who was for thirty or forty tism-may soon engage the earnest and undivided attention years a member of that Society. He communicated some of our leading men of science, and induce them to counte. of his earliest papers to it before publication of its Transnance and second my isolated and hitherto scarcely appre-actions was undertaken. The Council have also caused a ciated efforts by honouring with a fair, impartial, and portrait medal of the value of £10 to be struck, and this candid criticism those novel and original views and prin. they propose to award every third year for the best original ciples I have ventured to advance and to publish in this | investigation, either in chemical physics or in pure or and preceding communications.

applied chemistry, which may be communicated to the Society or to its Chemical Section in the interval of the awards. The choice as first Graham Lecturer appro.

priately fell on Mr. W. Chandler Roberts, F.R.S., who A NEW FAST GREEN AND MALACHITE GREEN. had so long been associated with Graham's work, and

who was enabled to employ for the purposes of demonstra. By Messrs. BINDSCHEDLER and BUSCH.

tion much of the apparatus that had been used by his

distinguished master. A very large audience assembled Up to the present the so-called methyl-green has been on the 22nd of January in the Hall of Glasgow University, obtained from dimethyl-aniline by converting the latter where Graham graduated in 1824, and the chair was at into violet by oxidation, and then the violet again by first occupied by Mr. James Mactear, President of the methylation into green.

Chemical Section, who pointed out that they were doubly It has long been the endeavour of the manufacturers of fortunate in having secured the services of Mr. Roberts, aniline colours to get the green dired from dimethyl. 1 and in the fact that Mr. James Young, F.R.S., of Kelly,

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