22 Molecular Determinations in Solutions. I regret that I made the groundless and utterly erroneous assumption that "Suum Cuique" was not acquainted with the classical experiment of Cavendish; seeing that it is by no means the best known of his experiments, I imagined that probability was against his having known it. I am sorry that, in attributing ignorance to him, I used the unnecessary word "blissfully," and admit that the annoyance I must have caused him justifies his free use of adjectives. {CHEMICAL NEWS, stated that Prof. Ramsay is not the chemist with whom A process of this sort, described by Ostwald, was put Lord Rayleigh would have associated himself had he in practice by Walker, and by Will and Bredig, but it been left a free agent. It looks very much as if Prof. involves too great an expenditure of time; even for a Ramsay's scientific work is to be belittled, because ex- liquid as volatile as alcohol a single experiment occupied ception is taken to his conduct from an ethical standpoint. twenty-four hours. Would it not be more manly to state any real grounds of By the method here described a single experiment occomplaint that may exist, than to assail his work inaccu-cupies, when once the apparatus has been constructed, rately and anonymously? about twenty minutes, and it can be repeated in ten. It consists of a couple of well-corked test-tubes, each fitted like a Woulff's bottle, with a tube dipping nearly to the bottom, and a short outlet tube with one bend; in one of these test-tubes is placed the solution, in the other the pure solvent. One of the outlet tubes is put in communication with an aspirator, and the dipping-tube of the other testtube in communication with the air-cistern-a closed vessel into which the water of the aspirator is allowed to run. Thus a current of air is drawn through the liquid in the one test-tube and driven through the other, the quantities of air in each case being approximately equal. This approximation is sufficiently exact when by changing the connections the current, under the same conditions, has been reversed. The difference still remaining is due to the difference of vapour pressure between the two liquids, and it may be got over by saturating the air with the pure liquid, as under aspiration it issues from the test-tube containing the dissolved substance. The advantage seemed, however, on trial to be more theoretical than practical. In conclusion, Sir, I hope, as a student of Prof. Ramsay's work, that he and his colleague will not be led by this discussion to defer publication of any more results till they have isolated all the gases of the atmosphere in a state of absolute purity, and have determined the whole of their properties: I believe I shall voice the opinion of a considerable section, if I say that the publication of their results as they get them will be welcomed as an addition to the world's knowledge.-I am, &c., H. DROOP RICHMOND. St. Margaret's, July 5, 1898. MOLECULAR DETERMINATIONS IN SOLUTIONS. To the Editor of the Chemical News. SIR, If it be the case, as mentioned in the paper by Messrs. Jones and King (CHEMICAL NEWS, Ixxvii., p. 243), that the boiling-point method is the only one at present applicable to the generality of solvents, it may doubtless be of interest to describe a process which under some circumstances may be found useful. I tested it some time ago with satisfactory results. It is generally applicable to all, or at all events to the more volatile solvents, not limited strictly to one particular temperature, but workable for a considerable range below the boiling-points. It is independent of any constants special to different liquids. It is, moreover, capable of being applied rapidly, and with no further equipment than is found in every laboratory. The principle of the method is the measurement of vapour pressure by means of evaporation. With a liquid evaporating, the number of vapour molecules per unit volume of the space above will be proportional to the pressure of the vapour. If the space-i. e., if the air above the liquid is renewed as fast as saturated, the number of molecules carried off will be proportional to the vapour pressure. This will also be true when different liquids are compared, and when a pure liquid is compared with the same liquid containing a non-volatile dissolved substance. The presence of substances in solution lowers the pressure, the amount evaporated is diminished, the diminution of the quantity evaporated is a measure of the diminution of pressure. To apply this in practice it is, of course, not sufficient simply to leave the pure liquid and the solution to evaporate under similar conditions of pressure, temperature, and extent of exposed surface. The changes of concentration at the surface of the solution are too tardily counteracted by diffusion; the decrement of evaporation is far greater than it would be if the process were simply determined by the average concentration. A uniform concentration throughout the liquid and a uniform evaporation, however, can be secured by blowing through the solution and the pure solvent approximately equal quantities of air. The temperature was kept uniform by means of a (generally cold) water-bath, in which the test-tubes stood. To keep them dry, for greater convenience and correctness of weighing, they were surrounded by two closefitting cylinders of thin copper, blocked at the bottom, which were inserted in the closed top of the water-bath; thus the test-tubes were not in contact with water or water-vapour. The test-tubes were fitted with rubber corks of two holes; but in the case of carbon disulphide, benzene, and such solvents as rapidly pass through indiarubber, these had to be replaced by ordinary corks capped with sealingwax. The weighing of the test-tubes and contents was done with the corks and glass fittings in situ. Special precautions in the case of volatile solvents had to be taken with the capping of the small glass tubes. Part of an old Kipp's apparatus was extremely serviceable as aspirator; the construction enabled the amount of water passed to be very accurately controlled. For water and liquids of low volatility the whole of the water-bath with the test-tube should be put in a wateroven, and so arranged that the connections can be changed on the outside. This will prevent the solvent from condensing on the outlet tubes, which it would otherwise do if only the water-bath were heated. With such apparatus, when both test-tubes are charged with the pure solvent the difference of the amount evaporated ought not to differ by 1/10th per cent. For the purpose of the experiment the air passing must be saturated. This renders the application of heat necessary in the case of liquids of non-volatility equal to toluene. For such a liquid as carbon disulphide it made no difference whether the dipping-tubes passed 9 c.m. or 1.5 c.m. into the liquid; but, of course, for the sake of equalising the pressure, both dipping-tubes should go to the same depth (they may be graduated for the purpose). This question of pressure seems to prevent the use of two blow. throughs, — with one suction arrangement and one blow-through it is greatly neutralised. -- Where advisable it is possible to substitute any other gas for air. Of course the air must be dried as it passes from the air-cistern. The rate of air-flow is without effect on the result, but splashing inside the test-tubes must be avoided. Of course the concentration of the solution varies during the experiment, the average concentration has to be calculated for. Not more than 1/10th of the whole solu. tion need generally be evaporated. CHEMICAL NEWS,} July 8, 1898. Chemical Notices from Foreign Sources. 23 plate with paraffin as in M. Becquerel's sxperiment. The whole was left in the dark from December 24, 1897, until April 27, 1898. After developing the plate, it was found that the iron ring under the jar had made no impression, but that the ring placed directly on the sensitive film had produced an image of a slightly larger size than the ring itself, and therefore extending beyond the line of contact. This experiment shows that the phenomenon is not due to radiations, but to a volatile body produced by the iron. On a Borocarbide of Glucinum.-P. Lebeau.—Al Or if q be the amount evaporated from the pure solvent, q' the amount evaporated from the solution, N the number of gramme-molecules of solvent in the solution, the number of gramme-molecules of the dis-ready inserted in full. solved substance Some Halogen Salts of Lead.-V. Thomas.-The object of this note is the study of the chloroiodides of lead. The action of boiling hydrochloric acid on iodide of lead always gives rise to a chloroiodide, PыICl. If iodide of lead reacts on a chloride, or chloride of lead on an iodide, the result is always the same,-PbICI is formed. The existence of the chloroiodide as a welldefined chemical compound is shown by the product of oxidation it is able to form when treated with peroxide of nitrogen. Thermic Data relating to Ethyl-malonic Acid. Comparison with its Isomers, Glutaric and Methylsuccinic Acids.-G. Massol.-Anhydrous ethyl-malonic acid dissolves in water with a heat of absorption of -2.96 cals. The heats of neutralisation are-for CH7O4K, CHEMICAL NOTICES FROM FOREIGN +14'08 cals., and for CH604K2, +13.80 cals. The heat SOURCES. of formation of a solid neutral salt, from the solid acid and base, is NOTE.-All degrees oftemperature are Centigrade unless otherwise C5H8O4 sol. +2KOH sol.= expressed. Comptes Rendus Hebdomadaires des Séances, de l'Académie des Sciences. Vol. cxxvi., No. 19, May 9, 1898. Method for the Detection and Estimation of Car. bonic Oxide in the presence of Traces of Carburised Gas in the Atmosphere.-Armand Gautier.-To determine the amount of carbonic oxide in air, the air, previously deprived of all dust, acid gases, and water, is passed through two tubes, the first o'28 m. in length, containing iodic anhydride, and the second o'18 m. long, containing pure powdered copper (reduced by hydrogen): these tubes are sealed together in such a manner that they can both be placed in an air-oven and heated to 100-105°. This amount of copper is quite sufficient to take up all the iodine given off, no matter how dilute the vapour may be. A number of experiments which follow show that this method is sure and convenient in the ordinary cases when the air, or other inert gas, contains not more than 1/10,000th part of carbonic oxide. But the figures given, however satisfactory they may be in an ordinary case, may not be so certain when there is only a trace of carbonic acid present. To settle this point another potash tube was added at the end of the copper tube for the purpose of collecting the last traces of iodine, and then, for eight hours, a quantity of air containing enough CO2 to set free nearly 15 m.grms. of iodine was slowly circulated through the apparatus. The iodide stopped by the copper The author then goes on to describe further experiments for the purpose of eliminating any hydrocarbides which may be present. Vaporisation of Iron at the Ordinary Temperatures.-H. Pellat.-The following experiment whs made by the author:-A small iron ring was laid directly on the sensitive surface of a bromo-gelatin plate; at its side another similar ring was placed, but separated from the sensitive surface by a very thin sheet of microscopic cover glass; the latter was covered by a bell-jar fastened to the =C5H604K2 sol. + 2H2O sol. + 48′25 cals. The comparison of the values of the three isomers shows that the acidimetric value measured thermically by the heat of formation of a solid neutral potash salt, varies for each of the three isomers : Position 13 ethyl-malonic acid +48.25 cals. 1:5 normal-glutaric acid + 44'23,, Formation of Furfurol by Cellulose, and its Oxy. and Hydro-derivatives. Leo Vignon. The author took equal weights of pure cotton cellulose, and submitted them respectively to the action of (1) acids, (2) oxidising agents, and (3) reducing agents. He obtained three substances; these were left in contact with a cold solution of caustic potash, at 10° B. for five hours; the first and third gave a colourless liquid, the second one a liquid of a pale yellow golden colour; after washing and drying it was found that Nos. 1 and 3 had undergone a loss of weight of 15 per cent, and No. 2 of 25 per cent. Thus oxycellulose is distinctly different from hydro-cellulose, which appears to be identical with hydrogenised cellulose. These were then submitted to the action of boiling hydro. chloric acid at 106 density, and the furfurol obtained was estimated in the distillate collected, and transformed by phenylhydrazin into hydrazone, according to the fol lowing equation: C5H4O2+C6H5N2H3=C5H2ON2HC6H5+H2O. Berichte der Deutschen Chemischen Gesellschaft. Organic Derivatives of Selenium.-A. Michaelis and A. Kunckell.-By acting on the ether oxides of naphthol, on the phenols, and the ketones by SeCl3 various compounds are formed. The reactions take place in the cold in ethereal solution; it is fairly energetic. 2CH3-O.C10Hy+SeCl2 = (CH3O.C10H6)2Se+ 2HCI; this compound is a reddish crystalline mass, soluble in CHCl3, melting at 138°. The action of SeCl2 on phenol gives a red mass having the formula Se(C6H4OH)2. Some Organic Derivatives of Tellurium.-E. Rust.Tetrachloride of tellurium reacts on anisol, giving 24 Chemical Notices from Foreign Sources. THE OHEMICAL NEWS, The ARRANGEMENT OF ATOMS IN SPACE. TeCl2(C6H4.OCIH3)2, in yellow needles melting at 190°, soluble in ether, benzene, HCl, and the alkalis. chloroplatinate appears in the form of brown needles, soluble in water and alkalis. The hydrate, bromide, iodide, and nitrate have also been obtained and described. Tetrachloride of tellurium also reacts on phenetol, phenol, and resorcine. Antimonic Derivatives of Anisol aed Phenetol.C. Loeloff. These derivatives are obtained (1) by the action of Na on a mixture of SbCl, and bromanisol or bromophenetol; (2) by the action of bromanisol on antimoniate of soda. A large number of derivatives are de. scribed. On some Aromatic Compounds containing Bismuth.-A. Gillmeister.-Iodine acts on bismuth-triphenyl in ethereal solution, giving the oxyiodide of bismuth. The iodide, (C6H5)2Bil is obtained by treating an alkaline solution of the chlorine, (C6H3)3BiCl2, by KI. HgCl2 reacts on an alkaline solution of bismuth-triphenyl, giving BIOCI, benzene, and chloromercurate of phenyl. A mixture of nitric and sulphuric acids completely decomposes bismuth-triphenyl into nitrate of bismuth and ortho-di. nitrobenzene. On some Dissymmetric Substituted Phenylhydra. zines and their Derivatives.-A. Michaelis.-A certain number of substituted aß-phenylhydrazines have been prepared by acting on the soda derivative of phenylhydrazine with the alcoholic bromides; the reaction takes place on the water-bath in the presence of benzene. The author describes the hydrochlorate of a-ethyl-phenylhydrazine, ethylindolcarbonic acid, dichlorethyloxindol, dibromethyloxindol, and many other bodies and their derivatives. Action of Chloroform and Alcoholic Potash on Phenylhydrazine.-S. Ruhemann.-The action of nitric acid on diphenyltetrazoline furnishes two nitrated derivatives, one of which melts above 300° and is difficultly soluble in acetic acid. By reducing it by warm SnCl2 and HCl an amidodiphenyltetrazoline is obtained, crystallising in white needles, fusible at 188°, and soluble in alcohol. NOTES AND QUERIES, Second, Revised, and Enlarged Edition. and an Appendix, Stereochemistry among Inorganic LONDON, NEW YORK, and BOMBAY : CHEAP SETS OF STANDARD BOOKS. FOR SALE. THE CHEMICAL GAZETTE. Complete set (unbound), 17 Volumes, 1842—1859. Price £4 4s. net. Lane, Ludgate Hill, London, E.C. DAVY FARADAY RESEARCH LABORATORY Our Notes and Queries column was opened for the purpose of Address "Gazette," CHEMICAL NEWs Office, 6 & 7, Creed giving and obtaining information likely to be of use to our readers generally. We cannot undertake to let this column be the means of transmitting merely private information, or such trade notices as should legitimately come in the advertisement columns. Decolourising Oils. (Reply to H. Matthews).- Decolourising oils is a rather incorrect expression. There is no process for bleaching rape oils or oils for lubricating purposes; they are rendered paler, but they are not decolourised. This result can be attained by osone, which at the same time thickens the oil. Dark low-grade fats are transformed into a yellowish material without the use of acid.-EM. Andreoli. Physics of Gases. Could any of your readers inform me, through yourNotes and Queries" column, if there is any work or works from which I could learn something of the boiling- or liquefying. points of gases (including air), their behaviour under very high pressures, and also their influence or action upon metals. Said works should be as free as possible from technical terms and mathematics. I most particularly desire to know the behaviour under high pressures. Please state prices and publishers.- ENGINEERING STUDENT OF PHYSICS. ERRATUM.-Vol. lxxvii., p. 263, col 1, line 2 of the paragraph commencing" At the regular meeting," for "Breyer and Schweitzer read "Frear and Sweetser." OLD PLATINUM IN ANY FORM PURCHASED for Cash. OF THE ROYAL INSTITUTION. Directors: The Right Hon. LORD RAYLEIGH, M.A., D.C.L., LL.D., F.R.S. This Superintendent of the Laboratory: Dr. ALEXANDER SCOTT, M.A., D.Sc. his Laboratory, founded by Dr. LUDWIG MOND, F.R.S., as a Memorial of Davy and Faraday for the purpose of promoting original research in Pure and Physical Chemistry, will be open during the following Terms: MICHAELMAS TERM-Monday, October 3rd, to Saturday, December 17th. LENT TERM-Monday, January 9th, to Saturday, March 25th. EASTER TERM-Monday, April 17th, to Saturday, July 29th. Under the Deed of Trust, workers in the Laboratory are entitled, free of charge, to Gas, Electricity, and Water, as far as available, and at the discretion of the Directors, to the use of the apparatus belonging to the Laboratory, together with such materials and chemicals as may be authorised. All persons desiring to be admitted as workers, must send evidence of scientific training, qualification, and previous experience in original research, along with a statement of the nature of the investigation they propose to undertake. Candidates must apply for admission during the course of the preceding Term. Forms of application can be had from the Assistant Secretary, Royal Institution, Albemarle Street, W. ON THE POSITION OF HELIUM, ARGON, AND KRYPTON IN THE SCHEME OF ELEMENTS.* By Sir WILLIAM CROOKES, F.R.S. and it fulfils every condition of the problem. Such a figure will result from three very simple simultaneous motions. First, an oscillation to and fro (suppose east and west); secondly, an oscillation at right angles to the former (suppose north and south), and thirdly, a motion at right angles to these two (suppose downwards), which, in its simplest form, would be with unvarying velocity. IT has been found difficult to give the elements argon and helium (and I think the same difficulty will exist in respect to the gas krypton) their proper place in the scheme of arrangement of the elements which we owe to the ingenuity and scientific acumen of Newlands, Mendeléef, and others. Some years ago, carrying a little further Professor Emerson Reynolds's idea of representing the scheme of elements by a zigzag line, I thought of projecting a scheme in three dimensional space, and exhibited at one of the meetings of the Chemical Societyt a model illustrating my views. Since that time, I have re-arranged I take any arbitrary and convenient figure-of-eight, without reference to its exact nature; I divide each of the loops into eight equal parts, and then drop from these points ordinates corresponding to the atomic weights of the first cycle of elements. I have here a model representing this figure projected in space; in it the elements are supposed to follow one another at equal distances along the figure-of-eight spiral, a gap of one division being left at the point of crossing. The vertical height is divided into 240 equal parts on which the atomic weights are plotted, from H = 1 to Ur = 239'59. Each black disc represents an element, and is accurately on a level with its atomic weight on the vertical scale. The accompanying figure, photographed from the solid model, illustrates the proposed arrangement. The ele ments falling one under the other along each of the vertical ordinates are shown in the Table. Rh Ru Pd с F Ca Sc ᎢᎥ V Cr Mn Fe Ni Co Rb Sr Yt Zr Nb Mo Ba La Ce () ( ) ( ) () () Ir Pt Os Bi Th Ur Au Hg () () TI Pb the positions then assigned to some of the less known elements in accordance with later atomic weight determinations, and thereby made the curve more symmetrical. Many of the elemental facts can be well explained by supposing the space projection of the scheme of elements to be a spiral. This curve is, however, inadmissible, inasmuch, as the curve has to pass through a point neutral as to electricity and chemical energy twice in each cycle. A Paper read before the Royal Society, June 9, 1898. +Presidential Address to the Chemical Society, March 28, 1888. The bracketed spaces between cerium and tantalum are probably occupied by elements of the didymium and erbium groups. Their chemical properties are not known with sufficient accuracy to enable their positions to be well defined. They all give coloured absorption spectra and have atomic weights between these limits. Positions marked by a dash) (-) are waiting for future discoveries to fill up. Let me suppose that at the birth of the elements, as we now know them, the action of the vis generatrix might be diagrammatically represented by a journey to and fro in 26 Constituents of Indian and American Podophyllum. stages. Note, June 22, 1898.-Since the above was written, Professor Ramsay and Mr. Travers have discovered two other inert gases accompanying argon in the atmosphere. These are called Neon and Metargon. From data supplied me by Professor Ramsay, it is probable that neon has an atomic weight of about 22, which would bring it into the neutral position between fluorine and sodium. Metargon is said to have an atomic weight of about 40; if so, it shares the third neutral position with argon. I have marked the positions of these new elements on the diagram. cycles along a figure-of-eight path, while, simultaneously are interperiodic in the sense of being formed in transition time is flowing on, and some circumstance by which the element-forming cause is conditioned (e.g., temperature) is declining; (variations which I have endeavoured to represent by the downward slope.) The result of the first cycle may be represented in the diagram by supposing that the unknown formative cause has scattered along its journey the groupings now called hydrogen, lithium, glucinum, boron, carbon, nitrogen, oxygen, fluorine, sodium, magnesium, aluminium, silicon, phosphorus, sulphur, and chlorine. But the swing of the pendulum is not arrested at the end of the first round. It still proceeds on its journey, and had the conditions remained constant, the next elementary grouping generated would again be lithium, and the original cycle would eternally reappear, producing again and again the same fourteen elements. But the conditions are not quite the same. Those represented by the two mutually rectan gular horizontal components of the motion (say chemical and electrical energy) are not materially modified; that to which the vertical component corresponds has lessened, and so, instead of lithium being repeated by lithium, the groupings which form the commencement of CONSTITUENTS OF INDIAN AND AMERICAN the second cycle are not lithium, but its lineal descendant, potassium. It is seen that each coil of the lemniscate track crosses the neutral line at lower and lower points. This line is neutral as to electricity, and neutral as to chemical action. Electro-positive elements are generated on the northerly or retreating half of the swing, and electro-negative elements on the southerly or approaching half, Chemical atomicity is governed by distance from the central point of neutrality; monatomic elements being one remove from it, diatomic elements two removes, and so on. Paramagnetic elements congregate to the left of the neutral line, and diamagnetic elements to the right. With few exceptions, all the most metallic elements lie on the north. Till recently chemists knew no element which had not more or less marked chemical properties, but now by the researches of Lord Rayleigh and Professor Ramsay, we are brought face to face with a group of bodies with apparently no chemical properties, forming an exception to the other chemical elements. I venture to suggest that these elements, helium, argon, and krypton, in this scheme naturally fall into their places as they stand on the neutral line. Helium, with an atomic weight of 4, fits into the neutral position between hydrogen and lithium. Argon with an atomic weight of about 40, as naturally falls into the neutral position between chlorine and potassium. While krypton with an atomic weight of about 80, will find a place between bromine and rubidium. See how well the analogous elements follow one another in order: C, Ti, and Zr; N and V; Gl, Ca, Sr, and Ba; Li, K, Rb, and Cs; Cl, Br, and I; S, Se, and Te; Mg, Zn, Cd, and Hg; P, As, Sb, and Bi; Al, Ga, In, and Tl. The symmetry of these series shows that we are on the right track. It also shows how many missing elements are waiting for discovery, and it would not now be impossible to emulate the brilliant feat of Mendeléef in the celebrated cases of Eka-silicon and Eka-aluminium. Along the neutral line alone are places for many more bodies, which will probably increase in density and atomic weight until we come to inert bodies in the solid form. Four groups are seen under one another, each consisting of closely allied elements which Professor Mendeléef has relegated to his 8th family. They congregate round the atomic weight 57, manganese, iron, nickel, and cobalt; round the atomic weight 103, ruthenium, rhodium, and palladium; while lower down round atomic weight 195 are congregated osmium, iridium, and platinum. These groups are interperiodic because their atomic weights exclude them from the small periods into which the other elements fall; and because their chemical relations with some members of the neighbouring groups show that they | SOME OBSERVATIONS ON A PAPER BY ENTITLED "A CHEMICAL INVESTIGATION OF THE PODOPHYLLUM." By F. B. POWER, Ph.D., F.C.S. In a paper published in the Journal of the Chemical Society, April, 1898, pp. 209-226, bearing the abovementioned title, there are some errors and omissions which ought to be corrected. On page 209 the authors make the following statement :-" The chemical constituents of the rhizome of the American Podophyllum peltatum have, however, been made the subject of several investigations. First, in 1832, Hodgson prepared the mixture of resins known and largely used in medicine as 'podophyllin' by precipitating a concentrated alcoholic extract of the rhizome with water; this is now manufactured on a large scale, and is the form in which 'podophyllum' is usually administered as a drug. The first important contribution to the chemistry of Podophyllum was that made by Podwyssotski (Pharm. Journ. (iii.), 12, pp. 217, 1011). This chemist showed that the rhizome did not, as was previously supposed, contain the alkaloid berberine." From this statement the inference would naturally be drawn that Podwyssotski was the first to prove the absence of berberine in Podophyllum. The absence of berberine, or any other alkaloid, in Podophyllum was first conclusively proved and recorded by me in 1877, or four years before the publication of Podwyssotski's first paper on Podophyllum, as may be seen from the following extract from the Proc. Amer. Pharm. Assoc., 1877, p. 425:-"The rhizome of Podophyllum peltatum contains no berberine, and the colouring matter is a constituent of the resin itself; a fact all the more surprising when we consider that for a period of nearly half a century the supposed presence of this alkaloid in the rhizome should have become so universally accepted; and from time to time confirmed, without ever having been isolated from it." And again (loc. cit., p. 433), briefly summarise the results of these experiments, it may finally be observed that Podophyllum contains no alkaloid, and that the yellow colouring principle heretofore supposed to be due to berberine is due to the resin, and to that portion of it which is of acid character and which may with some degree of propriety receive the previously applied name of podophyllinic acid, which has also in chemical behaviour many analogies to quercitrin." 66 to Podwyssotski, indeed, never claimed to have first shown the absence of berberine in Podophyllum, but simply confirmed my observations that no alkaloid was present. In his chronological review of the investigations preceding his own (see Pharm. Zeitschrift für Russland, 1881, p. 888), he refers to a note by Flückiger in the French translation by Lanessan of the first edition of Pharmaco |