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ALTHOUGH the foregoing statements relate specifically to the first of the three great problems, similar principles apply to the second. If we are to determine what general laws connect the properties of compounds with those of the elements contained in them, we must first secure a large mass of well-established data to work from. For a very large number of substances, such constants as density, crystalline form, melting and boiling point, thermal conductivity, specific and latent heat, co-efficient of expansion, index of refraction, electrical resistance, and so on, ought to be rigorously ascertained. With such accurate data, we may hope to reach the desired laws; without them we can see but a little way. Moreover, every constant should be determined in a much more thorough manner than any have been determined hitherto. Every measurement should be repeated many times, and under all attainable conditions; otherwise the work would be manifestly incomplete.

Fragmentary researches of this kind have already been carried out in great number; but how? In some directions

Address before the Permanent Sub-section of Chemistry of the American Association for the Advancement of Science, at the SA Louie Meeting, August, 1878,

I have tried to collect the evidence, in order that we might know what data were really available, and where the worst gaps lay. The discrepancies which sometimes come to light are amazing. Take a large number of specific gravity determinations for any given compound, and see how discordant they are. The values will range through wide limits, so that it is often imposible to say which one out of several is the best. These variations may be due partly to bad work, and partly to unrecognised differences in chemical constitution. Some of them are so peculiar that they can hardly be expiained, except upon the hypothesis isomerism. The metallic iodides furnish some good illusthat they spring from some undiscovered allotropy or trations of this idea. The well-known properties of mercuric iodide, Rodwell's experiments upon silver iodide, and Cooke's researches into antimony iodide are sufficiently suggestive. When, therefore, we meet with discordant specific gravity determinations among other iodides, we may reasonably suppose that one experimenter has dealt with one allotrope, and another with another, both unconscious of any existing differences. But however this may be, the discordance of so many data, not only among specific gravity measurements, but in all other series of determinations, serves to show how little freshly, and how much ought to be done over again. Of we really know, how much work remains to be done all the figures upon which we now rely for the solution of these grander problems, at least three-fourths should be scrupulously re-determined; and even after that had been done our material would still be woefully insufficient. The kind of work we need may be well illustrated by the classical labours of Stas upon the atomic weights, and the immortal researches of Regnault into the physical properties of vapours. Such work as this will give imperishable foundations for exact science, strong enough and broad enough to sustain the most stately edifice which the human intellect can rear.

To my mind, the investigation of this sort most immediately needed is the accurate determination of all the physical constants for all the so-called elements. This would supply evidence directly related to all three of the great problems. We might thus learn something about the nature of the elements themselves, and how far the transformations of energy due to chemical action depended upon their individual characters; we should also be put in some position to predict the properties of compounds. In many important lines of research, science would then replace speculation, and the imagination could still find ample fields in which to exert its powers. As yet such work as this has not been done for even one of the sixty-five or sixty-six elements known. Take iron, for example, the most important of the metals, one which has been the subject of numberless practical researches,-and we as yet know it in these more purely scientific relations barely on the surface. Not a single series of physical constants has yet been thoroughly determined with regard to it, notwithstanding the light that such investigations might shed upon important industrial problems. We know a little here and a little there; a bit about its thermal properties and another bit about its electrical properties, but nothing systematically and well. As for gold, silver, copper, and mercury, rather more is known; but even with these elements not a tenth of what ought to be done has really been accomplished.

The reason for such incompleteness in chemistry is suf ficiently evident. Indeed I have already hinted at it. The labour of investigation hitherto has fallen chiefly upon the shoulders of volunteers, who have worked in great measure independently of each other, every man following his own particular bent. Part of the work has been done by teachers, in their odd moments of freedom from the drudgery of instruction; other portions were carried out by inventors, or by manufacturers with reference to special industrial questions. There has been little co-operation, and no organisation of efforts. The one class of investigators has sought for the glory which bril

58

Cultivation of Chemistry.

liant discoveries bring; the other has laboured to secure pecuniary rewards. Thus has our pure science grown unsystematically, and our applied science has been imperfectly applied. The two depend on each other; and the more complete pure science can be made, the simpler and more beneficent will its applications become.

CHEMICAL NEWS,
February 7, 1879.

that of teaching, and probably as much leisure for himsel
and his own ideas as before. Indeed, to carry out the
latter his opportunities would be vastly improved.
Who can doubt that such a laboratory would benefit
science? To have important data systematically deter-
mined, with every conceivable precaution and the best
appliances, would certainly be worth while. Every industry
involving applications of physics or chemistry would be
aided. The special problems of the ironmaster might not
be touched, and yet evidence would be discovered which
certainly than before. Precision would be gained every-
where; in facts, in methods, and in appliances; theories
would rest on more solid foundations; the intellect would
find new food for thought. The work done might seem at
first sight to be of the hardest, driest, and most practical
character; and yet there would be within it more than
utility. We cannot deepen our knowledge of the real
without at the same time broadening our insight into the
ideal. The more we know, the vaster the unknown seems
to us. The better we know, the more truly do we recog-
nise the imperfections of our knowledge. We climb each
mountain only to see a bluer, higher, grander summit far
beyond.

Can this conception of a laboratory for pure research be realised? I believe it can. Physics and chemistry have created millions upon millions of wealth; they have helped to bring distant countries nearer together; they have benefited every human being within the limits of civilisation. In every country of the civilised world there are many rich men who owe their wealth to the applica tions of these sciences. In our own country especially, we find such men ready and often anxious to give. Every day we hear of large bequests for public purposes; of gifts to colleges, libraries, observatories, and museums; to hospitals, asylums, and churches; to the poor and to the heathen. Surely some of the wealth which our science has rendered possible ought to come back a little more directly for her benefit. There must be men who would give liberally to her purposes if they only knew of her needs. Can we not do something towards making our wants known? Are we not able to present a strong case in our own favour? Might we not by some combined effort at least make a beginning, and secure a fund, which should serve as a fulcrum for our future exertions? Let a nucleus once be established near some large university, or under the control of such an institution as the Smithsonian, and it cannot fail to grow. If the first organised laboratory, for such work as I propose, could be founded in this country, it would soon be recognised as a nationa glory and a benefactor of the whole human race. I throw out these suggestions merely as suggestions, with the hope that some means may speedily be found which shall lead us to the much desired end.

What chemistry needs, then, is combined effort upon some general plan. There must be a body of trained workers under an efficient head, who shall mark out some of the lines for investigation to follow. Such a cooperation can hardly be brought about under existing cir-should enable him to solve them much more easily and cumstances and with present facilities, since as a matter of course every scientific man prefers to work independently, and to shape his researches for himself. Something may be done, perhaps, by those college professors who are fortunate enough to have a considerable number of advanced students to assist them; but work carried forward under such conditions can scarcely amount to more than a clearing of the ground. Still such pioneer labour is not to be despised. It marks out many useful pathways for us, and shows where the chief difficulties are to be encountered. The one great method, however, by which the desired ends may be attained is to be found in the establishment of endowed laboratories devoted to pure research. With regard to laboratories of this kind much has been written, both for and against. From two distinct points of view has the subject been treated. One set of writers has opposed the idea of endowing research, upon what appear to me to be wholly fallacious grounds. They have urged that the payment of salaries to scientific men, either as a reward for past services or as a means of encouraging future work, would probably result in the foundation of sinecures in which pretentious idlers might find an excuse for doing nothing. A man could easily pretend to make investigations, and in reality only fritter away his time in a sort of elegant leisure. No endowment would render brilliant discoveries certain, so that fruitlessness might find ready apologies. This is a somewhat extreme statement of the case, though not a wholly unjust one. Such forebodings as these might be realised, although it does not to me seem probable that the men who now labour so earnestly and assiduously for the love of knowledge would accomplish any less because of greater encouragement. Still an endowment which afforded large salaries for no regular, specific duties, might in some cases work mischief. The true man of science would hardly advise even a possible wasting of means. The idea of an endowed laboratory for research is of a very different kind. It proposes an institution in which salaries shall be paid for work of a definite, prescribed character. Men would not be employed in it to make showy discoveries, although these might be rendered incidentally possible. The laboratory would, in short, be a place wherein the fundamental data of chemistry and physics should be accurately established, without more than casual reference to particular industrial questions or to theories. In it a body of trained specialists would cooperate upon such researches as I have suggested; they would fix some of the foundation stones of science; they would combine their strength upon those tasks which are too large and too arduous for individuals to undertake. Just as an astronomer makes an exact map of a given zone in the heavens, observing the position of each star over and over again; so the workers in this laboratory would undertake repeatedly those delicate measurements which physical science so much needs. The physical properties of substances could be exactly determined; methods of measurement could be tested and improved; apparatus too expensive for individuals to own might be constructed and employed; the quantitative relations of the several forces could be accurately ascertained. One great problem at a time might be taken up, and the energy of the whole body of workers concentrated upon it. Under ordinary existing circumstances a scientific man teaches several hours a day, and after that he labours at research. Here he would have a different routine from

In Europe the needs of science are often liberally provided for by Government. The scientific institutions of Germany, for example, owe their existence and support chiefly to funds drawn from the public treasury. This policy I believe to be wise and proper, although it might not be judicious to urge it strongly here. With us, the proposal to establish a purely scientific institution, upon moneys raised by general taxation, would undoubtedly be seriously opposed. The public importance of the measure would be obscured by a clamour about economy, and upon the wickedness of expending the means of the many for the benefit of the scientific few. Much of this opposition would be foolish, although at the same time effec tive. Still, granting that it might be unwise to ask the National Government to establish a laboratory for research, there is another kind of laboratory which it might build, equip, and organise, with unquestionable propriety.

All the time the General Government finds it necessary to employ chemists for special expert work. For the Bureau of Engraving and Printing investigations are made with reference to the inks and paper used in the manufacture of notes and bonds. Questions are con

NEWS

Science, I may be permitted to broach one more subject which I believe to be of some importance. Year after year the researches of American chemists are steadily increasing in number, extent, and value. Work like that of Gibbs, Cooke, Smith, Mallet, Remsen, Jackson, and a dozen others who might be named, is certainly work of which we may reasonably feel proud. But how is all this material published? A little of it in the American Journal of Science and Arts; a part in certain foreign periodicals; another portion in several local transactions, as for example the Proceedings of the American Academy. In short, the work is widely scattered, and some of it is effectually buried beyond the reach of a majority of our fellow chemists. We need, I believe, in this country, á good chemical journal which shall fairly represent the work that America is doing for chemistry. A journal in which every chemical research published in the United States should find a place, either in full or in abstract, would certainly stimulate investigation among us, and send all over the world a truer estimate of our scientific standing. We might have for our organ a chemical periodical equal to any in the world, and I sincerely hope that we may not have to wait long for its establishment. Where or by whom it should be edited and published is a question I will not attempt to raise; suffice it to say that it ought to be controlled by no local clique, and managed in no Pharisaical spirit. It should be broad enough not to fear novelty, and courageous enough to reject trash; two qualifications more easily stated than found. I throw out these suggestions, hoping that they may take root somewhere, and that without much delay. Even though we ourselves may lack the power to carry them out, our recognition of their importance may lead to action elsewere. If we in our gatherings can point out good pathways, others with richer means may be induced to follow them. Our united counsels and combined efforts may achieve results where, working separately, we should fail.

tinually arising in connection with the custom houses, which can only be settled by the testimony of a reliable chemist. Frequently the Examiners of Patents would be much aided in their decisions if they had laboratory facilities at their command. The War and Navy departments are continually needing work done, it may be in the examination of supplies, in testing metals, or in experiments upon explosives. For the Lighthouse Board there are oils to be tested, and for the Geological Surveys there are rocks and minerals to be analysed. As for the Agricultural Department, it already has a small laboratory, and there is another connected with the Army Medical Museum. These examples do not by any means complete the list; they only serve to show how great an amount of scientific labour the National Government is obliged annually to employ. The work is now done in a scattered way, often with imperfect appliances, and much less thoroughly than is desirable. The question I now raise is this: Would it not be eminently proper for the Government to establish a first-class chemical and physical laboratory, in which all of its work in these departments should be done by an adequate body of scientific men, provided with the best materials and apparatus? Would not this be a measure of true public economy? Could not more and better work be done for a given sum of money than is done now? To me it seems that the plan is decidedly practical, and that Congress might by judicious pressure be induced to carry it out. Of course the measure is open to the usual political objections. It might enable inefficient men to get responsible positions through political influence; and there would be a possible danger that corruption should secure another foothold where it is already too firmly lodged. This objection I do not believe to be sound. At present experts may be employed through political favour, while the country at large knows nothing of what is going on. In a national laboratory the appointments would be conspicuous, and mismanagement would at once be recognised. There is 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 laboratory could be made as efficient as the Naval Observatory, 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 must get the work done somehow, and would it not be best done in the manner I propose?

Such a laboratory as this, organised at first for the merely practical work of the Government, might in course of time widen its scope a little. The National Observatory, established originally for the purposes of the Navy Department, has been able to do much for science beyond its purely routine labours. The expenditure of public money for eclipse and transit expeditions, in furnishing the means for work like that of Newcomb and Hall, has been for the interests of abstract science; but I doubt whether any intelligent citizen has ever begrudged a dollar of it. The nation has been ennobled by such researches, even though no material benefits should ever spring from them. So with a national laboratory. At first its work would be only a technical routine; but sooner or later this would necessarily develop into something more. The Government investigations could not be carried on for ever by imperfect methods; and accordingly better_methods would have to be devised. What ever researches tended towards improving the work done for the nation would, of course, be properly carried out in a national laboratory. Thus an institution, established for practical purposes at public expense, could at the same time benefit the public service, and advance the interests of science. The cost would be justified over and over again in a purely material way, so that the question of the usefulness of the laboratory could never be seriousl raised.

As we are gathered together for the Advancement of

THE SEVEN FUNDAMENTAL TYPES OF

ORGANIC CHEMISTRY,

66
OF THE TYPO-NUCLEUS THEORY,
By OTTO RICHTER, Ph.D.
(Concluded from p. 48.)

In passing on to consider the second stage of the process, we may suppose that, by a species of lateral movement on the part of the newly formed subjunct nucleus away from the outer or inner conjunct chamber towards the outer or inner subjunct chamber, that molecule, while it remains still firmly attached to the principal nucleus by means of its appropriate number of thermal bonds, will at length arrive at the particular point whence it may be brought to take up a fixed and well-defined position within the corresponding subjunct chamber, a position which it will undoubtedly continue to maintain after the whole system has returned from the nascent state of unstable equilibrium into the quiescent state of stable equilibrium. It is scarcely necessary to add that at the close of this second stage of the process no substitutional action has as yet taken place, the affected molecule having simply undergone that particular preparatory treatment which befits it for the exercise of its newly acquired chemical duties and functions. Finally, as regards the third and last stage of the process which, in the majority cases, involves the presence and co-operation of two contending molecules, its chief characteristic feature consists in the successive interchange of one or more thermal bonds with simultaneous transfer of their respective subjuncts from one principal nucleus to the other.

60

The Seven Fundamental Types of Organic Chemistry.

CHEMICAL NEws

{February, 7, 1879.

Reserving the fuller discussion of this important subjective and fascinating subject, in order to examine into the for a future communication, I shall here content myself with a brief enunciation of the general law which I hold to preside over this particular order of chemical phenomena. But before doing so it will be necessary for me to pass a few observations on the proper meaning and use of the technical terms "Multivalenice" and "Quantivalence," terms which, the reader will not fail to remember, have now and then formed the subject of very animated but far from satisfactory controversies in our leading journals and debating societies.

In pondering this question from the novel and more elevated standpoint of my "Typo-nucleus" theory, I was not slow in perceiving that a fatal error had been committed by either side of combatants in not sufficiently discriminating between the absolute substitutional power and capacity of a principal nucleus pure and simple and the relative substitutional power and capacity of that same nucleus when associated with a variable number and quality of outer or inner conjunct molecules.

From an extensive series of researches in this direction I have arrived at the interesting and all-important conclusion that in the former case the said power and capacity is always measured and expressed by one single thermal bond only, because it forms the only connecting link between the two semi-nuclei into which the original molecule has been made to resolve itself, while in the latter case the said power and capacity is always measured and expressed by the variable number and quality of those outer or inner conjunct molecules which have passed from the original state of conjuncts into the typically altered state of subjuncts. Now, in my mode of viewing the term, "Multivalence is correctly employed whenever we wish to indicate the aggregate number of chemically similar or dissimilar conjunct molecules that have entered into direct chemical union with a given principal nucleus, while the term "Quantivalence" is correctly employed whenever we wish to indicate the number of subjunct molecules into which the whole, or a certain part only, of associated conjunct molecules have been successively converted, it being distinctly understood that such conversion is invariably accompanied by the simultaneous formation of a corresponding number of as many thermal bonds as are lawfully required to serve as connecting links between the principal nucleus and its evolved subjuncts.

The preceding statements and explanations will, I trust, enable the reader to grasp the full scientific bearing and significance of the remarkable law above referred to, and which may be briefly enunciated as follows:-The substitutional power and capacity of a given principal nucleus, after it has entered into direct chemical union with a given number of outer or inner conjunct molecules is a variable and fluctuating quantity, which is measured and expressed pro tem. by the collective number of thermal bonds emanating from that particular set of outer or inner conjunct molecules which have been made to pass from the original state of conjuncts into the typically altered state of subjuncts."

It deserves to be borne in mind that the said power and capacity is entirely independent of the chemical nature of the element out of which the principal nucleus has been moulded, for that element is found to contribute not one single unit to the sum total of the thermal bonds collectively attached thereto. We are thus driven to the unexpected but inevitable conclusion that the substitutional power and capacity with which our modern speculators are in the habit of crediting the principal nucleus does not reside therein at all, but may be said to exist in a kind of latent state within the outer or inner conjunct molecules, until the conversion of the latter into the corresponding subjuncts causes that power and capacity to become revealed under the form of interchangeable thermal bonds which, as a variable and fluctuating quantity, are made to range between the more or less circumscribed limits of a well-defined maximum and minimum.

It is now time for me to dismiss this singularly attrac

last remaining set of fundamental types which I have represented as standing under the immediate control of the principle of polarity or chemical principle. This principle rests upon the hyphothesis that in their nascent or chemically active state of existence every species of molecules, from the simplest to the most complex, is capable of being transiently thrown into a state of electrochemical polarity. This new kind of agency is supposed to attain its maximum of force in the direction of a straight line intersecting the molecule at right angles to its operative axis, and coinciding with the polar axis of that molecule; while in a plane at right angles to that axis, which coincides therefore with the equatorial plane of that mole. cule, the said agency is supposed to attain its minimum. This hypothesis, strange and mysterious though it may appear at first sight, leads at once to the consideration of two possible alternatives. In the first alternative, any two conflicting molecules may be represented as confronting each other in such a way that the polar axis of the one becomes opposed to the polar axis of the other; while in the second alternative they may be represented as confronting each other in such a way that the polar axis of the one becomes opposed to the equatorial plane of the other.

Applying this hypothesis to the direct chemical union of two or more principal nuclei with each other, I have arrived at the conclusion that all the members of the outer adjunct type which embrace the true polyatomic alcohols and their numerous basic and acid derivatives owe their origin and formation to the first of these alternatives, and, again, that all the members of the inner adjunct type which embrace the pseudo-polyatomic alcohols and their numerous basic and acid derivatives owe their origin and formation to the second of these alternatives. It deserves special notice also that the typical differences arising from the circumstance that the chief component groups of the former class of molecules are co-ordinately, because axially and axially, united, while those of the latter class of molecules are subordinately, because axially and equatorially, united, are of such a nature as materially to interfere with the general law of molecular collocation and arrangement. From a host of well-established experimental facts and observations I have it in my power to prove that, while the general law continues to exercise an absolute control over all the members of the outer adjunct type, it is no longer applicable to the members of the inner adjunct type, where its frequent infringement is apt to give rise to a great number and variety of isomeric compounds, the formation of which seems chiefly to depend upon the precise order in which certain organic and inorganic bases or acids are made to unite with that class of molecules.

Having now submitted to the reader a brief and tolerably complete general outline of the seven fundamental types of chemistry as collectively exhibited and placed side by side in our model molecule, I may yet be allowed, in drawing to a close, to give vent to a few appropriate remarks and sentiments.

It is my humble opinion-an opinion that is probably shared by the majority of unbiassed and more calmly reflecting chemists-that, in the course of its marvellously rapid progress and development our science has at length arrived at that critical turning-point where its votaries are compelled to answer to themselves the question-"Is it meet and desirable in the face of such an overwhelming mass of ever-accumulating facts that we should still go on contenting ourselves with the adulterated and unpalatable compost of antiquated notions and untenable dogmas, hallowed though they may be by the honoured memories of so many deserving and illustrious experimentalists, and may it not be that our boasted knowledge and pretended insight into nature's secrets is merely a gross delusion and a snare, the natural result, in fact, of grave speculative errors and prejudices, which must inevitably melt away under the genial rays of a more profound and enlightened

NEWS

, 1879"

These direct greens are brought into the market under the names of New Fast Green, Malachite Green, &c., and possess about the same chemical qualities, but the mode of manufacture and the attention paid to the same, cause more or less a difference in brilliancy of shade and yielding. It is, however, very easy to distinguish direct greens from methyl-greens through the simple fact that wool, silk, or cotton, when dyed with direct greens, can stand a very high degree of heat without the green colour turning into violet; whilst stuff dyed with methyl-greens turns violet when brought into contact with an iron exceeding 120° of heat.

The aforesaid theoretical mode of Otto Fischer, in Munich, was published in the reports of the Berlin Chemical Society on August 11, 1877, under the title of "Condensations Producte Tertiärer Aromatischer Basen." Otto Fischer describes therein a new base, which he obtains by the reaction of dimethyl-aniline, chloride of zinc, and hydride of benzyl, and further states that oxidising the salts derived from his method led to the production of a beautiful bluish green colour.

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- starting-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 | Doebner, 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 bodies in the ordinary sense of the word, or whether these elements ought not rather to be regarded as more or less complex bodies that, under the dissociating influence of temperature, may, like other truly compound substances, be brought to resolve themselves into molecules of lower atomic weight, and presumably also of different chemical and physical properties, from their parent molecules. It is contended-and I think rightly so--that these wonderful spectroscopic discoveries are totally inexplicable on the prevailing biatomic hypothesis. What other hypothesis then, I would ask the reader in all humility, remains for our final adoption but that same polyatomic hypothesis which forms the theoretical basis of that very system of chemical philosophy I have been the first in expounding and elaborating-a system, moreover, which, with respect to the splitting up or condensation of chemically simple or compound molecules, presents no difficulties whatsoever, while it possesses in these two opposite tendencies a ready and fertile source for the complete elucidation of many hitherto obscure and unintelligible chemical phenomena. With regard to the fundamental axiom which underlies my whole chemical system, namely, that not only every species of chemically elementary molecules, but likewise every variety of chemically compound molecules, as embraced under the generic term "Model Molecule," aie made to exhibit relatively to the three conjugate axes of space the most perfect symmetry of form and atomic arrangement, I have yet to observe that our model molecule with its seven-chamber system, in order to satisfy the aforesaid fundamental law, requires to be doubled; in other words, that such molecules require to be united into one by joining them together with their inner adjunct chambers. t will at once be seen that, under this new aspect, the symmetry of the whole system is rendered perfect; and I may now state, in addition, that this re-duplication of our model molecule will not oblige me to alter my customary mode of notation, if it is taken for granted that any molecular changes in the right moiety of our model molecule are invariably and simultaneously accompanied by similar molecular changes in the left moiety.

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 reconstruction of the groundwork of theoretical chemistrya 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 have not as yet been crippled and paralysed under the withering influence of a perverse and unyielding dogmatism-may soon engage the earnest and undivided attention of our leading men of science, and induce them to countenance and second my isolated and hitherto scarcely appreciated efforts by honouring with a fair, impartial, and candid criticism those novel and original views and principles I have ventured to advance and to publish in this and preceding communications.

A NEW FAST GREEN AND MALACHITE GREEN.
By Messrs. BINDSCHEDLER and BUSCH.

Up to the present the so-called methyl-green has been obtained from dimethyl-aniline by converting the latter into violet by oxidation, and then the violet again by methylation into green.

It has long been the endeavour of the manufacturers of aniline colours to get the green direct from dimethyl

The exceedingly high price of the hydride of benzyl has hitherto prevented the practical application of Fischer's most interesting discovery. Now, however, this material is produced at a price which renders its practical use quite possible.

The process of manufacturing malachite-green is based upon the theoretical studies of Oscar Doebner, published in the reports of the Berlin Chemical Society, May 27, 1878.

Doebner proves in his report that green can be ob tained direct from dimethyl-aniline, chloride of zinc, and trichloride of benzol.

Besides the before-mentioned system of producing direct greens through the medium of hydride of benzyl, there are other methods by which the same can be obtained for instance, the product of the reaction of dimethyl-aniline, chloride of zinc, and dichloride of benzoyl, submitted to oxidation, gives a very beautiful and cheap green.

From the preceding statement it is obvious that different methods of manufacturing direct green exist.

THE GRAHAM LECTURE.

THF Philosophical Society of Glasgow have determined to institute a triennial lecture in memory of the late Prof. Graham, Master of the Mint, who was for thirty or forty years a member of that Society. He communicated some of his earliest papers to it before publication of its Transactions was undertaken. The Council have also caused a portrait medal of the value of £10 to be struck, and this they propose to award every third year for the best original investigation, either in chemical physics or in pure or applied chemistry, which may be communieated to the Society or to its Chemical Section in the interval of the awards. The choice as first Graham Lecturer appropriately fell on Mr. W. Chandler Roberts, F.R.S., who had so long been associated with Graham's work, and who was enabled to employ for the purposes of demonstration much of the apparatus that had been used by his distinguished master. A very large audience assembled on the 22nd of January in the Hall of Glasgow University, where Graham graduated in 1824, and the chair was at first occupied by Mr. JAMES MACTEAR, President of the Chemical Section, who pointed out that they were doubly fortunate in having secured the services of Mr. Roberts, and in the fact that Mr. James Young, F.R.S., of Kelly,

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