cent.

3. Moisture content of a charcoal was increased by addition of lime, common salt, or potassium carbonate. Unsatisfactory results were obtained as the mass tended to become sticky and unworkable. With phosgene, COCl2, the moisture would be advantageous, as decomposition into CO2 and HCI would be assisted. Further, the water would serve as a reservoir for the HCl. This gas was not studied as it could not be got in sufficient quantities; also, laboratory class work could not be interfered with.

4. Porosity of a mass of charcoal dust was increased by mixing with solid ammonium bichromate and beating out of air. The efficiency against gases was increased per cc. of actual charcoal, but per cc. of wbole product efficiency was low.

5. Decolorising power was tested, using caramel and indigo solutions, also highly discoloured crude glycerin. Birch charcoal dust was found a remarkably good decoloriser, but subsequent filtration was slow. Coarse charcoals do best at high temperatures, when penetration effect is considerable. Heating immediately before use drives from the charcoal any contained air or hydrocarbons, thus increasing the efficiency.

6. As gas adsorbents the denser charcoals were most efficient. The order of efficiency was found to be-palm nut, cocoanut, fruitstone. The values obtained by Hunter were not even approximately obtained. It is very probable that he used a highly specialised form of charcoal. State of division is an important factor. Fine dusts offer a large resistance to a gas and in large quantities there would be some difficulty in their use. Granules of about 1 mm. diameter were found suitable.

7. Selective adsorption.-Iodine residues were treated with chlorine water and iodine liberated removed by warming the solution with charcoal dust. The charcoal then filtered off and heated in an iron retort. The iodine sublimed into the neck of the retort and removed. The charcoal remaining was of little further use. In one case the charcoal was extracted with hot alcohol, but the process was slow and required a large volume of alcohol. The alcohol was subsequently distilled off from a water-bath, the iodine remaining. Both methods were found to be somewhat tedious in practice but fairly efficient as regards iodine yield. Iodine in iodates could be liberated by using bisulphite solutions after chlorine bad liberated iodine from iodides and such iodine had been removed as above. Later, selective adsorption will be studied as a means of removing alkaloids from alkaline extracts of vegetable tissues.

8. Adsorption of iodine from its solution in benzene and of benzoic acid from benzene was studied. The iodine was removed to a small extent comparatively, 17 per cent. Since iodine in KI solution exists as the ion 13, and is removed to the extent of 80 per cent under the same conditions of temperature, &c., it is probable that iodine in benzene exists in a simpler form. Benzoic acid was removed to the extent of 80 per cent; this points to benzoic acid molecules being associated in benzene.

It was noticed throughout the preceding work that the more complex in structure a substance may be the more readily is it adsorbed by charcoal. This fact should be useful in the case of alkaloid extraction.

PHYSICAL APPARATUS FOR CANADIAN UNIVERSITY.— A report has been received in the Department of Overseas Trade from His Majesty's Trade Commissioner at Toronto (Mr. F. W. Field) to the effect that a professor of a Canadian university desires to receive catalogues from United Kingdom manufacturers of physical apparatus for university laboratories for his guidance in placing orders. The name and address of the professor referred to will be furnished by the Department to any United Kingdom manufacturers interested, on application.

THEORY.

The 1920 atomic-weights are given alongside the ones deducible by means of the scheme. The significance of Note 1 of Part IV. is now made more apparent.

The order of the elements in the above table is necessitated by the scheme, and this agrees with that given by the atomic numbers.

Argon resembles beryllium in its composition, having apparently three outriders.

Cobalt and nickel have isotopes of mass 59, the others being 57 and 58 respectively. It looks as if the iron isotope of mass 56 is responsible for the high magnetisability of iron.

The regularity of odd and even valencies associated with odd- and even-number isotopes seems to break down at nickel and cobalt.

The calculated atomic-weights of nickel and iron when averaged become equal to the average of the experimental values, suggesting thereby a certain amount of perhaps unavoidable contamination in the experimental determinations.

From a study of the values obtained by the method of positive rays and these relations, I have come to the con. clusion that further experimental work on isotopes may reveal the fact that, under certain conditions of extreme dilution, it will be possible to get "mass spectra " of many metallic elements. Moreover, that some of the atoms may be broken up so that the values recorded are not always representative of those functioning in ordinary chemical actions, or in ordinary physical processes. There is also the possibility of a small percentage of contamina. tion due to what might be termed broken or disintegrated atoms-not necessarily due to radio-activity. This may account for the masses obtained by chemical methods deviating from the theoretical values; but, on the whole, the values seem very concordant: probably they are, for the most part, within the range of experimental error.

There is a regularity in the extended table which points to the possible modification of the nitrogen outrider, in that it may consist of two a-parts taken together instead of one more "compact" b-part; but as Sir E. Rutherford lays stress on the disrupted member of nitrogen having possibly a mass of 2 (see CHEMICAL NEWS, 1919, cxviii., p. 311), such evidence would appear possibly to contradict experiment. I am, however, aware that further experiments have been made which may clear up the difficulty. In the absence of full details of such experiments, this point cannot be discussed from the experimental side.

An attempt to explain the non-isotopic characteristic of C, N, O, and F has already been made (see CHEMICAL NEWS, 1915, cxi., p. 157), but there may be a further peculiarity as a contributory cause. These particula,

elements may be made up of sub-atoms of masses indicated by " in the table on p. 183, and the number (") may be 4 in each case.

EQUATION OF STATE.

By FRED. G. EDWARDS.

THE equation of molecular heat, namely, k = mx log T, may be converted into the equation of state b(k+a log 0) = mx log T, where e is the number of degrees below the critical temperature, a is an infinitesimal coefficient producing the relative values of the intrinsic pressures at the critical and observation temperatures respectively, and b is a constant making the sum in brackets equal to the intrinsic pressure, the surface tension, or the vo ume density, with any given units. The values of y obtained from m=595/y and m=4-(2y/295) will give the specific beats at variable volume, while m will be integral at the natural temperature of change of phase and recalescence. The specific density ratio D-Am≈ log T, and the coefficient of linear expansion

d.V/3d.Tid.1/Amx log TT/3Amx.

The atomic volume ratio V = 1/mx log T is a more general form of the equation of Lothar Meyer's curve V=A/D. | The tangent to the curve d.V/d.T=T/mx, and the minimum values d.2V/d.T =m-x = 0. Also, d.D/d.T= Amx/T. | The datum value of k will vary for each change of phase with the intrinsic pressure. The values of x are 0.0698A} generally, for certain gaseous substances 0.76384A, and for hydrogen, unity. It will be found that Groups V. and VI. of the Periodic Table form one homogeneous group as required for symmetrical atomic shape built up from a primordial mass unit, which may be nebulium. The coefficients of these equations can only be determined by a very extended analysis of the physical state of liquid and solid substances; but inspection shows that the terms are of the right order of magnitude, and, moreover, they are derived from an equation showing exact agreement with the specific heat at constant volume, and there is a distinct parallelism between the coefficient of expansion and the specific heat at variable volume.

THE

EXAMINATION OF CHINESE CRUDE CAMPHOR.
By E. R. DOVEY, A.R.C.Sc., A.I C.,
Government Laboratory, Hongkong.

Is the examination of crude camphor, the estimations usually required are those of non-volatile matter (or dirt), moisture, and oil, and the sum of these impurities subtracted from 100 per cent is supposed to represent the camphor present. The moisture may be conveniently estimated by the calcium carbide method, allowing three hours for the evolution of gas, and the dirt by the residue left after volatilising a weighed portion of camphor.

So far as is known to the writer, no reliable method for the estimation of camphor oil in crude camphor has been published, other than the melting-point method given in Allen's "Commercial Organic Analysis," vol. iv., p. 197. As this laboratory was called upon to examine a considerable number of Chinese crude camphors, the follow ing method worked out here may be of interest :-The moisture is first estimated on the well-mixed sample, then 100 grms., weighed to the nearest o'i grm., are transferred to a press and pressed between two layers of lint. The press designed for this work has a steel cylinder 2 inches in diameter and 6 inches deep, and is furnished with a movable perforated bottom plate. The piston is operated by a strong screw thread. The sample is allowed to remain in the press under pressure for fifteen

minutes, at the end of which time it is carefully removed and the pressed cake weighed, any camphor adhering to the lint being carefully brushed off and added to the cake. From the loss in weight the amount of water plus oil expressed is found.

The moisture is then estimated on the pressed cake, and from the difference between the result and the original moisture the amount of water expressed is found, and, by difference, the amount of oil in the expressed liquid is found.

It is then assumed that the water still remaining in the pressed cake is associated with as much oil as that in the expressed liquid, and the total cil calculated on that basis. The accuracy of this assumption may be open to question, but, with a good press, very little moisture remains in the cake, while the m. pt. of the pressed camphor usually indicates a fairly high degree of purity.-The Analyst, June, 1920.

DETECTION OF MINUTE QUANTITIES OF PETROLEUM SPIRIT IN VEGETABLE OILS.

By MASAHIRO AIDA.

A NUMBER of methods for the detection of petroleum spirit in vegetable oils have been proposed. A careful study of these has shown that they are not satisfactory, but it has been found that Nastjukoff's formolite reaction may be applied successfully for the purpose as follows:The oil (50-100 grms.) is saponified by means of potassium hydroxide solution. Distilled water and pure calcium chloride solution are added, the liquid distilled by means of steam, and the distillate treated with 40 per cent formaldehyde solution and a few drops of concentrated sulphuric acid. A reddish brown film coloration on the surface of the liquid, gradually changing to deep yellow, indicates presence of petroleum spirit. If a few drops of the distillate are added to water, a brilliant interference ring of optical waves is produced on the surface of the water; this ring becomes almost invisible after standing for some time and disappears completely on heating. With soya bean oil the ring does not change, even on beating. The above process is capable of detecting traces of petroleum spirit in vegetable oils, and may be made the basis of a quantitative method, the formolite precipitate being weighed after drying at 110-115° C.Journal Society Chemical Industry, June 15, 1920.

A REVISION OF THE ATOMIC WEIGHT OF TIN.* By HENRY KREPELKA.

We have determined in a new and more careful series of trials the ratio SnBr4: Ag by analysis of newly prepared tetrabromide of tin.

The materials for this purpose were prepared with great care and cleanliness, and chief attention was paid to removing all traces of moisture from the bromine used for the synthesis of the tetrabromide, and to keeping the latter in an absolutely dry state. Individual analyses were carried out in the same way as before (B. Brauner and H. Krepelka (Fourn. Am. Chem. Soc., xlii., No. 5), in the earlier work. The details follow. although one profited, of course, by the experience gained

Preparation of New Materials.

(The remaining reagents not mentioned here were prepared in the same way as stated in the preliminary work). Bromine.-Ordinary bromine was shaken in portions in a separatory funnel containing distilled water, every

• Presented to the Bohemian Academy of Sciences, Prague, 1919. From the Journal of the American Chemical Society, xlii., No. 5.

portion being thus treated three times. This bromine was then redistilled from a saturated solution of potassium bromide. The distillate was allowed to drip into a solution of potassium oxalate prepared by neutralising pure oxalic acid with pure potassium carbonate. The potassium bromide thus obtained was recrystallised three times, and its solution was evaporated with a small quantity of potassium dichromate and twice distilled sulphuric acid. The bromine thus set free removed all iodine that may have been present. This evaporation was repeated three times. In order to remove organic matter the dry bromide was melted in small quantities in a platinum crucible. From this remelted bromide bromine was set free by means of an amount of potassium dichromate and sul phuric acid, such as to leave undecomposed bromide in the distilling flask. The bromine was then redistilled, and from a portion of this distillate was prepared the calcium bromide used to dry the remaining part of the bromine, which was then further dried by shaking it with phosphorus pentoxide (twice sublimed in a stream of oxygen), and was afterwards distilled directly into the apparatus in which the synthesis of tetrabromide took place.

Tetrabromide of tin was prepared in the modified Lorenz apparatus. During the preparation the communication with the outside air was effected by a drying system (described in a previous communication-Fourn. Am. Chem. Soc., xlii., No. 5, p. 917) to which were added tubes containing sublimed phosphorus pentoxide.

The course of the reaction showed that both the bromine used and atmosphere of the reaction bottle were absolutely free from moisture, since the first drop of bromine did not at once react with the tin-foil-only after five minutes did the reaction begin slowly to take place. As soon as the first foil was covered with tetrabromide the reaction became violent and accompanied by such heat that the surrounding pieces of foil were melted into a ball, and the whole reaction bottle had to be quickly cooled.

The tetrabromide obtained was introduced into glass bulbs provided with cone-shaped necks and there sealed. This arrangement removed the difficulties encountered at the same operation during the preliminary work, when the bulbs used had straight necks.

Silver.-750 grms. of pure ordinary silver was dissolved in portions in distilled nitric acid (1:2) in such a way as to leave a small part of the silver undissolved.

The solution of silver nitrate thus obtained was heated, to the boiling point, and, after the expulsion of nitrous gases, was filtered. The clear solution, coloured pale blue by copper, was allowed to crystallise by evaporation. Silver nitrate thus obtained was fused in a porcelain dish until the melted mass became black. This black substance was dissolved in water, and the solution was filtered and allowed to crystallise by evaporation. The crystallisation was repeated three times. A spectroscopic examination of the last crystals showed only the lead line 3683 62 (intensity 1000), proving thus that all other metals had been removed.

The silver nitrate obtained in this manner was reduced by ammonium formate (prepared from pure formic acid and freshly distilled ammonia) and the reduced silver was washed with distilled water until the Nessler reagent gave no test for ammonia, dried in an electric drying oven at 150°, and then melted in a current of pure hydrogen according to the method elaborated by T. W. Richards (Journ. Am. Chem. Soc., 1905, xxvii., 472).

Pure hydrogen for this purpose was obtained by the electrolysis of a solution of pure sodium hydroxide prepared from pure metallic sodium. The apparatus used consisted of a long U-shaped tube, in one arm of which was evolved oxygen and in the other hydrogen. The arms were long in order to prevent the mixing of the two gases. The hydrogen was conducted into a purifying system composed of two Richards' washing flasks filled with a saturated solution of silver sulphate, a U-tube containing fused sodium bydrexide, a tube filled with red-bot pumice stone covered with platinum and of another Utube containing fused sodium hydroxide. The individual parts of the apparatus were connected by means of airtight ground joints.

Grains of remelted silver were etched with dilute nitric acid which had been redistilled, then washed successively in distilled water, ammonia water, and again in distilled water.

The final delicate operation, namely, the preparation of small pieces of pure silver for weighing, was carried out in the following manner :-The greater portion of the silver buttons was cut up into small pieces on a slab of pure silver with a sharp steel chisel the pieces were then etched and washed as above. The remaining grains were rolled between clean steel rollers in such a way that after each passing through the roller the silver was etched and washed in order to remove any trace of iron which it might have acquired. The silver foil was then cut by scissors into small pieces, which were then etched and washed as before.

Weighing was done on the same balance as in the preliminary work, but not until after the weights had been

tested and corrected.

Sx analyses were made in this series, and the results are given in the accompanying table.

Discussion. The mean value from six determinations is 118 699 (0.016). The maximum figure, 118.727, found only once, was arrived at by the analysis of Bulb No. 18, which was filled as far as to the neck. The minimum was 118 674. and this was the result of the analysis of Bulb No. 8, 1 kewise filled up to the neck. The maximum difference between the highest and lowest values is thus o 053. The mean value of all six ratios, SnBr: 4Ag. is 101586. The only probable source of error of this series of analyses appears to have been the space in the necks of the bulbs not filled with tetrabromide.

The agreement of the resulting mean value of the atomic weight of this series of analyses with the mean value of the preliminary determination increases the probability of this figure, and supports the value of the atomic weight of tin,

below the hot wire. It would be interesting to establish | if this were the case. Another interesting point was the connection, if any, between the central core of the hot column and the total width. When a hot body is standing in air there is a very definite zone of hot gas surrounding it. He had observed this recently by Zoepler's "schlieren" method (which he described), but it was not possible to say from the appearance of the currents above a candle-flame, for instance, whether an actual discontinuity existed at the edge of the current or not.

Mr. J. GUILD pointed out that these and other points could readily be investigated quantitatively by placing the apparatus in one beam of a Michelson interferometer arranged to give "Contour" fringes.

Mr. F. J. W. WHIPPLE referred to the practical applications such as the use of the instrument in an aeroplane. How would the results be effected by angular acceleration of the system?

Mr. F. E. SMITH emphasised this point. It appeared that this inclinometer would give precisely the same indication as a mechanical inclinometer, such, for instance, as a suspended bob or a marble in a glaas cylinder. In the two possible cases of unaccelerated flight, viz., right way up and upside down, there was never any doubt.

Dr. BARLOW asked if the pressure of the gas affected the results given by the instrument?

Dr. HOPWOOD asked how the behaviour varied with the diameter of wire used? Some time ago he had heated two loops of fine wire in series in coal gas. At atmospheric pressure the finer of the two glowed perceptibly and the other did not. On reducing the pressure it was possible to get the thicker wire glowing while the other was dark. Could any anomalous effects arise from such causes as this?

Mr. THOMAS, in reply, said that in a previous paper he had determined the ratio of the thermal conductivity of various gases to that of air. He had found the same ratio at 600° C. as at ordinary temperatures. He had interpreted this as indicating the existence of a skin of occluded gas round the wire. The thickness of this skin would be the term in King's formula. He had not yet investigated the conditions below the wire. Mr. Guild's suggestion of doing this with an interferometer was very interest ing. With regard to Mr. Smith's remarks he agreed that the instrument only indicated the apparent direction of gravity, but he had had the impression that there was some difficulty in discriminating between tight and wrong way up in certain cases, and that there was no satisfac tory indicator for this purpose in use. Another application connected with aviation is in setting the nose of experimental models exactly head on to the wind. Experiments had been made with various wires and no anomalies of

the type mentioned by Dr. Hopwood were found. The gas was at atmospheric pressure in practice.

A paper on "Convective Cooling and the Theory of Dimensions," was read by Mr. L. F. RICHARDSON.

viscosity of the gas. Langmuir had arrived at the opposite conclusion.

Mr. J. GUILD asked if in applying the theory of dimensions to the heat loss from bodies of different sizes, the considerations were not vitiated by the fact that the size and mean free path of the gas molecules were not varying with the other parts of the apparatus.

The AUTHOR, in reply, said that the effect mentioned by Mr. Gosling was apparent only. Actually from the nature of the other terms involved, the equation gave reduced values of the convection loss as the viscosity increased. As regards the invariant size of the gas molecules, mean free path, &c., probably the equations cease to hold when any of the dimensions become comparable with the mean free path of the gas.

Diffusing Circular Disc," by J. W. T. WALSH, was taken A paper entitled "The Radiation from a Perfectly as read, the author being absent.

NOTICES OF BOOKS.

Intermediate Text book of Chemistry. By ALEXANDER
SMITH. Pp. vi+520. 1920. London: G. Bell and
Sons, York House, Portugal Street, W.C. 2.
8s. 6d net.

Price

THE author has named this book " Intermediate," because it is shorter than his College Chemistry, but longer than bis Elementary Chemistry.

The book is divided into forty-three chapters, these giving divisions in the book. Chapters on Agricultural Chemistry, Foods and their Heating Values, and the Softening of Water are contained therein.

The chapter on Agricultural Chemistry contains articles on Plants, Fuels, and Food. It contains a brief outline of the substances used by plants as food and of the conditions which favour the growth of plants.

Chapters XXXI. and XLIII. deal with the recognition of substances, Chapter XXXI. with the non-metallic elements, and Chapter XLIII. with the metallic elements.

Organic Chemistry is introduced into the book only so far as to give a clear idea of the subject under discussion for instance, in Chapter XXXII., on Fats, Soaps, and Related Compounds, and in Chapter XXXIII. on Explosives and Plastics.

Physical Chemistry enters into the book a great deal, several chapters being devoted to the discussion of its

different branches.

In an appendix are given several useful tables, such as (1) the solubilities of bases and salts in water at 18°, (2) vapour pressure of water, (3) order of activity of the metals, and (4) International Atomic Weights (1917).

The book appears to be remarkably free from errors, and should prove a valuable help to those intending to take higher examinations in Chemistry.

DISCUSSION.

SOURCES.

There

took both forced and free convection into account. were many meteoric problems to which the application of the theory would be of value. Aitken bad compared the radiation and convection losses of bodies by exposing them to the sun and measuring their rise in temperature. Using a series of blackened cubes, he had obtained values for the convection which agreed roughly with Barratt's square root law, and would no doubt also fit in with the results of this paper.

Mr. GOSLING pointed out that formula No. 13 appeared to make the convection loss increase with the

des Science. Vol. clxx., No. 21, May 25, 1920. THE PLATING OF ALUMINIUM AND ITS ALLOYS.-MM. Léon Guillet and Maxime Gasnier.-The plating of aluminium and its alloys has been considered, till very recently, as an operation giving very unsatisfactory results owing to the feeble adherence of the deposit. A method, shown by M. Tassilly (Revue de Métallurgie, 1914, Mémoires, p. 670), based upon the previous attack of the metal by hydrochloric acid, has given commercial results. Having come to the conclusion that the adherence of the

deposit was simply due to an imperfect surface on the metal, the authors tried the very simple mechanical means and very effective method of producing this imperfection, that of spraying the surface with sand. The first results were very favourable, and the authors found that the following points had to be remembered in order to obtain the best results:

a. The quickness with which the grains of sand were projected on to the surface of the metal, which depends on the pressure of air employed.

b. The size of the grains.

Chimie et Industrie, April, 1920. TUNGSTEN.-M. Camille Matignon.-In the April issue of this journal M. Camille Matignon gives the second half of his paper on tungsten, which includes the manufacture of tungsten wire for electric lamps. The author has divided the processes of manufacture into three classes: -(1) Substitution, (2) by the help of an organic paste, and (3) by the use of colloidal tungstic acid. With regard to the first class, a carbon filament is brought to incandescence by an electric current in an atmosphere of bydrogen and tungsten oxychloride, thus giving a metallic filament according to the equations

Tungsten wire is also made by mixing tungsten powder with an organic paste, such as sugar, gum-arabic, dextrin, &c., and drawn into a wire. These wires are calcined in a reducing atmosphere, after which the wire is a mixture of tungsten and carbon. The wire is a sufficiently good conductor to allow an electric current to pass through it, so as to raise the temperature to 1100°, which is carried out in an atmosphere of hydrogen containing a little water vapour. The water vapour oxidises the carbon, but the metal is protected from oxidation by a sufficient pressure of bydrogen. During this operation the wires shrink to about three-fourths of their length, at the same time assuming a metallic lustre. The third class is the employment of colloidal tungstic acid, which has the advantage of not having to get rid of carbon. Wires obtained by one of these methods have a good metallic lustre, but they are brittle when cold. When warm they are pliable. The life of tungsten wire lamps is limited because of the tendency of the wire to become crystalline.

Revue des Produits Chimiques, May 15, 1920. PHYSICO CHEMICAL RESEARCHES INTO THE CONSTITUTION OF THE COBALTI-AMINES.-M. A. Job.-The researches of M. A. Job on the cobaltic pentamines have led him to adopt the general formula Co(NH3)5X3.4Ag. X stands for an electro-negative_monovalent radical (e.g., SO4.CI,OH, H2O, NO2, &c.). This gives the series Roseo and Purpureo. In the Purpureo series one of the X

on the oxidation of nitrogen, and secondly by combining nitrogen and hydrogen to form ammonia and the combustion of this latter product. The basis of producing the oxidation of nitrogen is by combining oxygen and nitrogen by means of an electric spark as shown first by Cavendish. The author mentions several types of furnaces used in the operation. The oxidation and hydrolysis are expressed by the following equations, with nitrous acid as an intermediate product:

Reaction (1) requires a high temperature, Reactions (2) and (3) are very rapid; they are opposed by a rise in temperature and by the presence of nitric acid in the watery liquor. The nitric acid liquor is concentrated either by concentration in vacuum or by distillation with sulphuric acid. With respect to the combustion of ammonia, catalysis comes into play, and MM. Pascal and Decarnère have studied various forms of catalysers (Bull. Soc. Chim., Sept. 19). They found that the mixture only reacted with an appreciable speed above a certain temperature, which depended on the form in which the platinum was used, but not on the duration of the contact. The oxidation of ammonia by air in the presence of platinum gives, first, nitric oxide and water; the nitric oxide is transformed by contact with the oxygen in the air into N2O3, NO2, and N204 (which is only stable above 150°). The transformation of the dioxide into the peroxide is not instantaneous. In conclusion, the author says that to solve part of the problem of synthetic nitric acid it is necessary to unify more completely the methods employed and to increase their number.

THE REPORT ON THE ECONOMIC CONDITIONS OF GERMANY.-This Report treats of the dominant factors in Germany economic and industrial and shows the condition of paralysis to which that country has been reduced by the_losses and liabilities of the war. The industrial machine is intact, but the wheels are turning very slowly. Even when the necessary raw materials are obtainable within the country the shortage of fuel and the reluctance of labour to exert itself reduce production to a fraction of what it was before the war. The collapse of credit makes very difficult and costly the purchase from outside Germany of materials for industries dependent upon foreign supplies. The report sums up the situation as follows:-"Germany has very nearly ceased to be a purchaser owing to the state of her exchanges, and we are presented with the spectacle of this country in urgent need of food and raw material lying impotent, unable either to satisfy her own requirements or to relieve her neighbours of accumulations which are rapidly becoming a burden to them. As Germany cannot buy, so also she cannot produce; she is, therefore,