times with ether. The ethereal solution is dried with potash, filtered, freed from ether by distillation, and purified by distillation under reduced pressure. The hydrosulphite reduction process has certain advantages over the methods of reduction in use. Sodium bisulphite is not a sufficiently strong reducing agent to bring about the reduction to hydrazine sulphonate readily, hence Fischer used zinc and acetic acid as the reducing agent, but this cannot be used without first forming the diazo sulphonate. Hence a somewhat more energetic reducing agent than bisulphite, which moreover affects the reduction directly, is preferable, especially as there is no risk of further reduction occurring at the hydrazine group. As compared with V. Meyer's process, the hydrosulphite method has the advantage of giving pure phenyl hydrazine hydrochloride, whereas in the former method practical difficulties are introduced by the presence of tin The hydrosulphite process gives a better yield than either of the other methods. The reactions are represented by the following equations CH,N2C1+Na,S,O,+H2O= CH,NH. NHSO,Na+NaCl+SO2. C.H,NH. NHSO,Na+HC1+H2O= the conditions given above, or, indeed, under any of our experimental conditions. This is due to several factors. p-Nitro phenyl hydrazine differs from the hydrazines already dealt with in being further reducible both at the hydrazine group and the nitro group the ultimate reduction product being p-phenylene diamine. Consequently, the sulphonic groups cannot be removed from the hydrazine disulphonate by the further action of hydrosulphite. Moreover, it is not theoretically possible to prepare the hydrazine disulphonate by the action of hydrosulphite alone, whether the latter goes to sulphite or sulphate, and there is no monosulphonate. Furthermore, the product of the reduction always resinifies, thus accounting for the presence of unreduced diazo sulphonate. The best yield of hydrazine was obtained under the following conditions: 42 grms. of p-nitraniline were boiled with 200 cc. of water and 100 CC. of concentrated hydrochloric acid, and the solution cooled in a freezing mixture. This was diazotised at a low temperature by rapidly adding 24 grms. of sodium nitrate dissolved in 50 cc. of water. The filtered diazo solution was treated with 30 cc. of concentrated hydrochloric acid, stirred mechanically, and slowly reduced at a temperature not exceeding 2° C. with 130 grms. of hydrosulphite dissolved in 700 cc. of water. The solid product contained both the hydrazine hydrochloride and hydrazine disulphonate, and gave 13 grms. of the hydrazine base after hydrosodium acetate. The mother liquor gave 6 grms. of the base on neutralising, and after salting out the remaining hydrazine disulphonate, this gave a further 4 grms, of the base. By extracting with ether a further small quantity was obtained. This makes a total yield of 24 grms. or 53 per cent of the theoretical. When the reduction is carried out in sodium carbonate solution, the main product appears to be p-nitro diazo benzene imide. CHINH.NH, HC1+NaHSO. Phenyl hydrazine p-sulphonic acid. This can be readily prepared by a method similar to that used for preparing phenyl hydrazine, employing either one molecule or two molecules of hydrolysing and treating with sodium carbonate and sulphite. In the latter case the hydrazine is obtained directly with a yield of about 53 per cent. Using one molecule of reducing agent the method is as follows: The solid diazo anhydride is first prepared by dissolving 19 grms. of recrystallised sulphanilic acid in 23 cc. of 20 per cent caustic soda and 100 cc. of water. Seven grms, of sodium nitrite are added, and the solution is poured into a cold solution of 12 cc. of strong sulphuric acid in 100 cc, water. The precipitated diazo compound is filtered off. The diazo compound in the form of a paste is reduced with a cooled solution of 22 grms. of hydrosulphite in 125 cc. of water, 20 cc. of hydrochloric acid being added during the reduction. The clear yellow solution of the p-sulphonic acid of phenyl hydrazine sulphonate of sodium which is thus produced, is easily hydrolysed by boiling with a further 30 cc. of hydrochloric acid. The free hydrazine is obtained directly as this hydrazine derivative forms no hydrochloride; 8:5 grms. of the pure base are obtained on crystallising, and the mother liquor gives a further 3 grms. on boiling down. This gives a total yield of 60 per cent of the theoretical, calculated on the original amine. C.H. N: N SO,H.C,H,NH. NHSO,Na+NaCl+SO2. SO,HC,H,N2H2SO,Na+H20= SO,H.C,H,NH. NH,+NaHSO,. It is interesting to note that the theoretical quantity of reducing agent is employed, whereas in the ordinary method about 24 times the theoretical quantity of bisulphite is generally used. Para-nitro phenyl hydrazine.-The reduction of p-nitro benzene diazonium chloride with hydrosulphite does not give satisfactory results under Para-nitro phenyl hydrazine can, however, be prepared by reduction of sodium p-nitro isodiazo benzene with hydrosulphite in alkaline solution, the method being similar to that used for the esti mation of this diazo or nitrosamine compound. The product is a tautomeric form of p-nitro phenyl hydrazine which is supposed to have a quinonoid structure and forms a sodium salt, as shown by Baly and Tuck (J. Chem. Soc., 1906). NaO N–NH, This gives the ordinary hydrazine on neutralising with acid. The product obtained in this preparation consists of a mixture of p-nitro phenyl hydrazine with a small proportion of the hydrazine disulphonate. It is best to isolate the nitrosamine compound and to carry out the reduction fairly rapidly so as to minimise the proportion of hydrazine disulphonate formed. Under certain conditions the product is obtained on neutralising in a finely divided form which is difficult to isolate. This is obviated if the acid hydrolysis is carried out as described below without isolating the hydrazine. The production of hydrazine compound was shown by titrating the solution resulting from this preparation to be practically quantitative. 28, The nitrosamine compound is obtained by pouring the diazo solution into caustic soda, as described by Schraube and Schmidt (Ber., 27, 514). Ten grms. of the pure nitrosamine compound, NO,C,H,N2ONa,2H,Ó, was mixed with a little water containing 6 grms. of caustic soda and reduced at o° C. with 20 grms, of hydrosulphite dissolved in 120 cc. of water. Some of the hydrazine base crystallised out as the quantity of alkali was only slightly in excess of that required by the equation : NO,C,H,N2ONa+2Na,S,O,+3NaOH= NO,C,H,N,H,+4Na2SO,. 200 cc. of hydrochloric acid was added and the solution boiled, in order to hydrolyse the small quantity of hydrazine sulphonate present. On neutralising the cooled solution with sodium carbonate and sodium acetate, 6'2 grms, of p-nitro phenyl hydrazine was obtained. Ether extraction of the mother liquor gave a further o'3 grm, of the base. The total yield is 95 per cent of the theoretical. Meta-nitro phenyl hydrazine.-The action of hydrosulphite on in-nitro benzene diazonium chloride under various conditions was investigated with the object of preparing m-nitro phenyl hydrazine. The reduction is analogous to that of the p-nitro compound, but only comparatively low yields of the hydrazine (40 per cent) were obtained, together with the hydrazine disulphonate, the diazo sulphonate, and, when working in sodium carbonate solution, the diazo imide. Use of titanous salts for the reduction of diazo compound. It has been stated in a previous paper that phenyl hydrazine is not obtained by the action of titanous salt on benzene diazonium chloride, the product being diazo benzene phenyl hydrazide, which is a condensation product of the diazo compound with phenyl hydrazine. In the case of diazotised p-nitraniline a similar reaction pro bably occurs, as only about half the theoretical quantity of reducing agent is used up. By carrying out the reduction with this reduced quantity of titanous sulphate, a bulky red precipitate was obtained which was extracted with alcohol and treated with sodium carbonate. The product thus obtained was free from titanium and contained no diazo imide. It was insoluble in cold water, decomposed by hot water, and melted at 65-70° C. By treating with alcoholic potash or alkaline hydrosulphite and then acidifying, p-nitro phenyl hydrazine was formed. Hence the substance was probably a diazo hydrazide, and although the compound NO,C,H1N: N.N(NH)C,H,NO, has not been previously described, Bamberger (Ber., xxviii., 840) obtained a very similar compound of the formula NO,C,H,N: N.N. (NH)CH1. It has now been found that analogous reactions take place when stannous chloride and bisulphite of soda are used as reducing agents, the equivalent of only one molecule (=2H instead of 4H) of either of these being sufficient to prevent the coupling of a solution of diazotised p-nitraniline with 3-naphthol. These results have some bearing on the method of producing white resists under insoluble azo colours in calico printing. In the printing of stannous chloride and bisulphite resists on B-naphthol prepared cloth under diazotised p-nitraniline or a-naphthylamine, it is generally assumed that the diazo compounds do not touch the printed parts owing to their being instantly reduced to hydrazine compounds. This evidently does not take place, and the fact that no colour develops is due to other causes. Presumably in the case of diazotised p-nitraniline, a precipitate of the insoluble diazo hydrazide is immediately formed where the diazo compound comes in contact with the stannous chloride. Furthermore, the stannous chloride used is capable of destroying, as far as the coupling effect is concerned, twice as much of the diazo compound as if it brought about the reduction to the ordinary hydrazine. In the case of diazotised meta-nitraniline, a similar reaction apparently occurs, but here the diazo hydrazide is further reducible either by titanous or stannous salts, and it has therefore been possible to prepare m-nitro phenyl hydrazine by using titanous sulphate as reducing agent. The product of the reduction is a yellowish-orange frothy precipitate, which is remarkably bulky. After filtering and extracting with hot alcohol, the alcoholic solution gives a flocculent precipitate of what appears to be the titanium double salt of m-nitro phenyl hydrazine. Such double salts of titanium with a salt of an organic base are very rare, and an attempt was made to purify some of this as the oxalate, but it could not be obtained crystalline. The free hydrazine base was obtained from the solution of the double salt by treating with sodium acetate, boiling, and filtering from the residue of titanic hydrate. The yield of the base thus obtained is 65 per cent of the theoretical. This method of preparation does not seem to be of much value, owing to the practical difficulties which are encountered. Thus it is evident that sodium hydrosulphite can be used with advantage in the preparation of hydrazine derivatives, in place of bisulphites and stannous salts, which have formerly been almost invariably used. In certain cases titanous salts may be used for the purpose, but do not offer any advantages In conclusion, I wish to thank Prof. Knecht for his direction and supervision of this work. THE CHEMISTRY AND CRYSTALLOGRAPHY OF SOME FLUORIDES OF COBALT, NICKEL, MANGANESE AND COPPER.* By FLOYD H. EDMINSTER and HERMON C. COOPER. (Continued from p. 30.) Cobalt Fluoride Analysis. The fluorine of the cobalt fluoride was determined by adding an excess of standard alkali to the water solution. The precipitate was four times washed by decantation with hot water, whereupon it was brought upon the filter and washed with hot water until the washings gave no test for alkali with phenolpthalein. The filtrate was then titrated with standard hydrochloric acid and the weight of sodium hydroxide used was calculated. In order to check this method, determinations were made by precipitating the fluorine with calcium acetate. The results were lower than by titration, and are not considered reliable. A more detailed account of this work was submitted to the Faculty of the Graduate School of Syracuse University by Floyd H. Edminster in May, 1918, in partial fulfilment of the requirements for the degree of Doctor of Philosophy. 44 Fluorides of Cobalt, Nickel, Manganese, and Copper [G All of the general methods were used for deter mining cobalt metal. The first method employed was that of precipitating with sodium hydroxide, filtering the precipitate, and washing it with hot water. The dried hydroxide was ignited and the oxide decomposed with concentrated sulphuric acid. This acid solution was then evaporated to dryness and the anhydrous cobalt sulphate weighed. Another method used for cobalt was to treat the fluoride with sulphuric acid and evaporate. This should volatilise all of the constituents except the metal. Consistent results were obtained by this method which agree with the electrolytic determinations. The reaction with sulphuric acid is vigourous and complete within a few minutes. The sulphuric acid is then driven off in an airbath, the residue heated for five minutes and eventually weighed as anhydrous cobalt sulphate. In electrolytic deposition, cobalt does not behave ideally; it does not always form a good coating on the cathode, but often scales off before the deposition is complete. We carried out the electrolysis as specified by Treadwell-Hall (Treadwell-Hall, “Analytical Chemistry" II., 1915, p. 138, 4th ed., N.Y.). Our experience has been that, if the voltage exceeds 15 volts, the cobalt will precipitate as the hydroxide, and, if the solu tion is not kept strongly alkaline, a black ring will be deposited, particularly around the edge. A voltage of 10 to 15 and an amperage of ro to 13 gave the best results. A 100-cc. platinum basin served as the cathode. It is not necessary to precipitate the hydroxide of cobalt, but the crystals may be dissolved in water, ammonium hydroxide added, and the solution electrolysed directly. The possibility of contamination with alkali is eliminated and accurate results are to be expected, but no determination of fluorine can be made on the same sample. Cobalt hydroxide was also reduced to the metal by the Rose method. Unfortunately, the ignited precipitate was always in masses, which would not reduce unless removed from the crucible and ground. If this was not done, the reduction was incomplete, and the results were too high. Nickel Fluoride Analysis. In the nickel fluoride the fluorine was determined as in the case of cobalt. The metal also was determined (1) as the anhydrous sulphate, after evaporating the fluoride crystals with sulphuric acid; (2) by electrolysis; and (3) as the oxide. Unlike cobalt oxide, nickel oxide has a constant composition and the metal can be calculated from the weight of the oxide. Anhydrous nickel sulphate is hygroscopic and must be weighed quickly after removal from the desiccator. The electrolysis was conducted in a strongly alkaline solution with a voltage of about 15 and an amperage of 15. In all cases the platinum basin was used as the cathode. No analyses for nickel were made by the Rose method. Copper Fluoride Analysis.-The copper is best determined (1) by electrolysis in the water solution of the crystals, which are acid with hydrofluoric acid, unless the fluorine is to be determined in the same sample. In the latter case, the copper is precipitated as the hydroxide, dissolved in dilute nitric acid, and subjected to electrolysis. Copper was also determined (2) by evaporating the crystals with sulphuric acid. (3) When the CHEMICAL NEWS copper fluoride crystals are heated alone, they give off water and hydrofluoric acid and are converted to the oxide. The weight of copper calculated from the oxide thus obtained agrees approximately with that obtained by other methods. Manganese Fluoride Analysis.-The fluorine was determined by the same method as for the other fluorides. The metal was determined (1) by decomposing with sulphuric acid, and (2) by converting to the pyrophosphate. For the latter method the manganese is first precipitated as the hydroxide, washed free from alkali and dissolved in dilute sulphuric acid. The Analytical Data.-The results of the analyses are tabulated in the following tables. The numbers in the first column are analytical reference numbers; the method employed in the analysis is indicated in the second column; the weights of salt and constituent, respectively, are given in the next two columns; the computed percentage is found in the fifth column; while below will be found memoranda that might aid in the appraisal of the results. Cobalt Fluoride. Prepared by the action of HF on the hydroxide or carbonate, no difference being seen in the products. Reference No. Salt. Fluorine. Per G. cent. 6 Pptd. as CaF2 0*3000 O'1214 39'97 3 Titration 0'5000 O'1310 41°30 0*3000 01285 41*45 42.85(a) PROCEEDINGS OF SOCIETIES. ROYAL SOCIETY. Ordinary Meeting, January 20, 1921. PROF. C. S. SHERRINGTON, President, in the Chair. THE following papers were read :— "The Magnetic Mechanical Analysis of Manganese Steel." By Sir ROBERT HADFIELD, S. R. WILLIAMS, and I. S. BOWEN. was The This paper is an attempt to correlate some of the magnetic and mechanical properties of manganese steel. Tests were made on six rods quenched in water, when they are in the nonmagnetic condition, and three were afterwards annealed, which renders them magnetic. changes in length of the rods when subjected to magnetic fields were determined (Joule Effect). In the case of the rods in the magnetic condition the change an increment for all field strengths. No change in length to o ̄000004 cm. could be detected for the non-magnetic specimens. The effect on the intensity of magnetisation when subjected to longitudinal stress was investigated (Villari Effect). An absolute method of measuring the intensity of magnetisation when comparatively small was adopted, consisting in the use of an exploring coil made up of two coils in series so arranged that the E.M.F. generated in the first balances that in the second, and calibrated by means of a long solenoid of general dimensions equal to those of the rods tested. For all field strengths the application of tensile stress increased the intensity of magnetisation of the magnetic specimens. The non-magnetic rods showed no change in intensity of magnetisation by being stretched. They did, however, show an intensity of magnetisation about 1/36 of that of the specimens in the magnetic condition. This effect was found to be entirely due to oxidation of the skin of the rods, for, on removing a few thousandths, the specimens showed no magnetic susceptibility when tested by a hand magnet. "A Selective Hot-wire Microphone." By W. S. TUCKER, D.Sc., and E. T. PARIS. The instrument consists of an electrically heated grid of fine platinum wire placed in the neck of a Helmholtz resonator. The effect of a sound having the same frequency as that natural to the resonator itself is to produce an oscillatory motion of the air in the neck of the resonator, which in turn causes changes in resistance of the platinum wire grid. The total resistance change comprises a steady fall in resistance, due to an average cooling of the grid and a periodic change due to the to-and-fro motion of the air. Two methods of using the microphone are described : (i.) A Bridge method, depending on the steady drop in resistance, and (ii.) An Amplifier method which makes use of the periodic resistance changes. Curves are given showing the sharpness of resonance a smeasured by the Bridge method. The various factors affecting the sensitivity of the microphone are discussed. Results of experiments on cooling the grid by low-velocity air-currents are described. It is deduced that the principal resistance changes to be expected when the grid is cooled by an oscillatory air-current are: (1) A steady drop due to an average cooling; (2) A periodic resistance change of the same frequency as that of the sound; and (3) A periodic resistance change of frequency twice that of the sound. Further All these effects are found in practice. deductions are that the steady change of resistance is proportional to the intensity of the sound, while the periodic resistance change in (2) is proportional to the amplitude. These conclusions are confirmed by experiment. "Siren Harmonics and a Pure-tone Siren.” By E. A. MILNE and R. H. FOWLER. The ordinary siren can be regarded as a point source of air variable flux, the flux being proportional to the area of the orifice exposed by the holes in the disc. In general the tone from such a siren is far from pure. The relative intensities of the harmonics for a siren with circular holes and a circular orifice are calculated and compared with experiment. It is concluded that a fairly pure note should be obtained from a siren of this type, in which the distance between the centres of adjacent holes is twice the diameter of the holes. If, however, the original is rectangular in section, the holes can be so shaped that the area of the orifice exposed varies exactly as the sine of the displacement. Such a siren should produce a very pure tone. Experimental tests of a siren constructed on these lines are quoted and discussed. "Design of Diaphragms capable of Continuous Tuning." By L. V. KING. In designing submarine sound generators and receivers it is important to be able to tune the diaphragm to a desired pitch, thus realising selective transmission and reception. A type of diaphragm so constructed that continuous tuning is achieved by the application of air-pressure (or suction) was designed by the writer and is designed in detail. It is constructed from a single piece of metal, and consists of a thick, undeformable, central disc, connected by a thin, concentric, annular portion, to a heavy circular rim, which is fited very accurately on a rigid mounting. The application of air-pressure over the interior of the diaphragm alters the tension of the thin annular portion, so that the rigid central portion vibrates about the static equilibrium position with a different pitch. A steel diaphragm, 3in. in diameter, was constructed in the manner described. A range of pressure from -25cm. of mercury to +25 cm. altered the pitch of the diaphragm vibrating in air from 430 to 620, and vibrating in water from 370 to 530. By comparing the frequencies corresponding to the same pressures on the diaphragm when vibrating in air and water, it is shown that the accoustic mass amounted to as much as 40 per cent of the actual mass. To realise sharp tuning and high sensitivity, it was concluded as a result of experience that diaphragms of this type should be made with almost optical precision in the form of accurate solids of revolution. CORRESPONDENCE. GLUCOSAZONE SULPHURIC ACIDS. To the Editor of the Chemical News. SIR, While the glucosazones are well-known compounds, their sulphuric acids do not seem to have been prepared and described. A short investigation of these bodies was undertaken early in 1920, with the following results. (1) Sodium phenylglucosazone para sulphurate was prepared by heating phenylhydrazine para sulphuric acid with glucose and sodium acetate in aqueous solution it was obtained as a pale lemon yellow powder, very soluble in water, slightly soluble in absolute alcohol, and insoluble in ether, acetone, benzene, &c. I have not succeeded in crystallising it. (2) Sodium phenyllactosazone para sulphonate was prepared in the same way, and has similar properties. (3) Sodium naphthylglucosazone 1: 4 sulphonate was obtained in a similar way from naphthylhydrazine 14 sulphuric acid (prepared from naphthianic acid): it is a powder similar to the above, though not such a pure colour, These osazones are dyes similar to phenyl glucosazone para carboxylic acid described by Kodak, Ltd., in the British Journal of Photography in 1919. It is clear that by the use of halogen and other derivatives of phenyl and naphthylhydrazine sulphuric acids many new osazones could be prepared; also various sugars and substances such as glycerine aldehyde which contain the group -CHOH-CHO might be employed. Since one molecule of a sugar combines with two of a hydrazine derivative to form an osazone, it seems to me probable that two further series of compounds could be prepared; (a) where one molecule of a sugar combines with one molecule of a dihydrazine derivative obtained from diamines such as phenylene and toluylene diamines; |