NEWS acid. Silver, in combining with chlorine, evolves 34,800 heat units, and hydrogen, combining with iodine in presence of water to form aqueous hydrochloric acid, develops 15,004, the sum being 49,804 units; on the other hand, silver, in combining with iodine, yields 18,651 units, and hydrogen and chlorine, in the presence of water forming aqueous hydrochloric acid, 40,192, the sum being 58,843 heat units. This amount of heat is greater than that developed in the former case, and therefore double decomposition takes place, with production of argentic iodide. the metals, which corresponds with the order of their affinity for zinc, iron, tin, lead, copper, mercury, and silver. In those elements which, like phosphorus, sulphur, and carbon, are susceptible of allotropic modifications, the heat of combustion is as their specific heats; thus charcoal, when burnt, evolves more heat than graphite. If we compare the heat evolved by the combination of any metal, say potassium, with chlorine, bromine, iodine, and sulphur, we shall invariably find that more heat is evolved in the formation of the chloride than in that of the bromide, and similarly, on comparing the bromide with the iodide, and the iodide with the sulphide; moreover, if the metals be arranged according to the amount of heat evolved in the formation of either the chloride, bromide, iodide, or sulphide, the order will always be the same, viz., that of their affinity. Further, supposing a metal, M, combines with chlorine and with bromine, forming the corresponding chloride and bromide, and that a second metal, M', also combines with chlorine and bromine, the thermic relation, expressed by the equation MCI MBr M'CI M'Br, is approximately true; for instance, zinc, in combining with chlorine, evolves 113,134 heat units, and with bromine 89,714, whilst lead similarly devolves 85,322 and 62,578 units. R. ANGUS SMITH, Ph.D., F.R.S., Vice-President, in the ZnCl (113,134) - ZnBr (89,714) = 23,420 heat units, and PbCl (85,322)-PbBr (62,578) = 22,744 heat units, numbers approximately the same. After noticing the interesting results obtained by Professor Thomsen by the combination of hydrogen with the metalloids, the lecturer passed on to the heat evolved by the burning of organic compounds, noticing that isomeric bodies do not develop the same amount, as, for example, ethylene, C2H4, and paramylene, C20H4O, the former of which evolves 11,858 heat units, and the latter only 10,928. Moreover, it is not possible to calculate the amount of heat produced by the combustion of organic substances; thus, acetylene (C2H2) evolves 310,570 heat units when burnt, and two of hydrogen (H2) evolve 68,357, the sum being 378,927. And we should expect that ethylene (C2H4=C2H2+H2) would evolve this amount when burnt; but, in reality, we only obtain 334,800, being a difference of 44,122 units, which is, perhaps, expended in overcoming the affinity which unites the H2 with the C2H2. By extending the numbers thus obtained to marsh-gas (CH4) we may calculate the latent heat of carbon vapour in the following manner :-One molecule of solid carbon, on burning, will develop 93,600 heat units, and four of hydrogen 136,714, from which we must subtract 2 × 44,122, or 88,224 units, representing the heat absorbed in overcoming the affinity between the carbon and four of hydrogen contained in marsh-gas (CH4), giving a total of 142,060 units; by experiment, however, we find that the combustion of marsh-gas develops 209,900 heat units. This difference of 67,840 units represents, therefore, the latent heat of carbon vapour. The thanks of the Society having been tendered to Dr. Debus for his interesting and instructive lecture, the President adjourned the meeting until Thursday, May 1st, when papers will be read "On Zirconia," by J. B. Hannay, and "On a New Class of Explosives," by Dr. H. Sprengel. SOCIETY. MANCHESTER LITERARY AND PHILOSOPHICAL Chair. Mr. J. S. Kipping and Mr. J. Sidebotham were appointed "Note on an Observation of a Small Black Spot on the Sun's Disc," by JOSEPH SIDEBOTHAM, F.R.A.S. As there is again some speculation as to the existence of an intra-mercurial planet, and every little fact bearing on the subject may be of value, I have referred to my diary, and find that on Monday, March 12th, 1849, our late member, Mr. G. C. Lowe, and I saw a small circular black spot cross a portion of the sun's disc. We were trying the mounting and adjustments of a 7-inch reflector we had been making, and used an ink-box between the eye-piece and the plane speculum. At first we thought this small black spot was upon the eye-piece, but soon found it was on the sun's disc, and we watched its progress across the disc for nearly half an hour. The only note in my diary is the fact of the spot being seen; no time is mentioned, but if I remember rightly it was about 4 o'clock in the afternoon. Mr. BAXENDELL, on behalf of Mr. Sidebotham, F.R.A.S., exhibited a knife, the blade of which is steel, the bush at the handle brass, and the handle itself copper, all coated with nickel, beautifully polished. In a letter which Mr. Sidebotham had received from Professor Hamilton L. Smith, of Hobart College, Geneva, N.Y., the writer suggests the use of iron or bell-metal specula, coated with nickel, for reflecting telescopes. He says, "I ground and prepared a bell-metal speculum, which I coated with nickel, and this, when polished, proved to be more reflective (at least I thought so) than speculum metal. The two objects which I sought were-first, to have a polished surface unattackable by sulphuretted hydrogen (this, for example, is not injured by packing with lucifer matches); and, secondly, for large specula, doing most of the work by the turning-tool and lathe. I really think a large, say 3 feet, mirror, coated with nickel, but cast of iron, and finished mostly in the lathe, while it would not cost the tenth of a similar sized speculum metal, would be almost equal to silvered glass of the same size, and vastly more enduring as to polish. In a series of homologous alcohols or acids, it would appear that the heat developed on combustion is less the higher we ascend in the series, that is to say, the more complicated the molecule becomes, which we may suppose to arise from the molecular work performed in packing the molecules more closely together, as it were. The speaker finally made a few remarks on the thermic effects of solution, and of the combination of acids and bases, particularly drawing attention to the fact that, whenever a salt dissolves without producing a compound with the water in definite proportions, heat is absorbed; for example, on adding sufficient water to dry cupric sulphide or calcic chloride to form a crystalline salt, heat is developed, but, on dissolving the crystals so formed in water, heat is absorbed and the solution becomes colder, the molecular state of a solution_differing from that of ordinary chemical combination. The fact that in double E. W. BINNEY, F.R.S., F.G.S., Vice-President, in the decomposition that compound is always formed which develops the greatest amount of heat is well exemplified by the action of hydriodic acid on argentic chloride, which, as is well known, yields argentic iodide and hydrochloric PHYSICAL AND MATHEMATICAL SECTION. Chair. The following gentlemen were elected officers of the Section for the ensuing year : NEWS President-Alfred Brothers, F.R.A.S. the East Indies, which had been sent to him for analysis Vice-Presidents-Joseph Baxendell, F.R.A.S.; Samuel with a view to advising as to their utilisation. The results Broughton. Treasurer-Thomas Carrick. of the examination were rather interesting. Lake deposits were known to occur in several countries-in Central Secretary-George Venables Vernon, F.R.A.S., F.M.S. Africa, in various parts of Asia, and in North and South GLASGOW PHILOSOPHICAL SOCIETY. (CHEMICAL SECTION). Ordinary Meeting, April 14th, 1873. Mr. JOHN JEX LONG, Vice-President, in the Chair. THE PRESIDENT (Dr. Wallace, F.R.S.E.) read a paper on "The Mortar of the Great Pyramid," in which he gave a number of interesting details regarding the mortar employed in building the Great Pyramid; and incidentally referred to the composition of some mortars that he analysed a few years ago, including two from the exterior and interior of the Great Pyramid, two specimens of very ancient Phoenician mortar from the island of Cyprus, two from ruins at Athens, and from Rome and from other places in Italy. It was most interesting to observe the remarkable differences between the mortars of the various ancient peoples. By going to Baalbec and other ruined cities of Turkey in Asia, buildings might be found constructed of immense blocks of stone jointed with such excessive nicety that even the blade of a penknife could not be pushed between them, but without a vestige of mortar. In the structures of the ancient Egyptians, on the other hand, taking the Great Pyramid as an example, mortar was freely employed, but consisting almost entirely of gypsum or sulphate of lime. A specimen was examined from an ancient Phoenician temple, the highest stone of which was a few years ago 5 feet below the level of the ground at the time the specimen was taken. It was something like that found in some of the baronial castles in this country, and was like a piece of solid rock. The gentleman who brought it home supposed it to be the very oldest mortar in existence. If it were so, Dr. Wallace said that it was most remarkable, inasmuch as it was as perfect in constitution as it could possibly be, having been made evidently of burnt lime, fine sand, coarse sand, and gravel. It might be called concrete rather than mortar. At any rate, one thing was certain, namely, that the lime in it had become completely carbonated; and another specimen of the same age exhibited the same phenomenon, thus satisfactorily settling a point which was long in dispute. The ancient Greek mortars from ruins in the vicinity of Athens were also very perfect, but contained more lime than that from Cyprus, and no gravel. The mortars from various ruined buildings in Herculaneum, Rome, and its neighbourhood, appered to have been made from burnt lime and puzzuolana, or what is called by geologists volcanic ash. Dr. Wallace stated that he had had some correspondence with Professor Piazzi Smyth regarding the mortar of the Great Pyramid, some portions of which he read; and he gave the following analysis of a specimen which he had recently examined :: America, where there are seasons of excessive drought, and where many salt-lakes have no outlet, not a few of them being far below the level of the sea. Examples were found in the Dead Sea, Lake Aral, and the Caspian Sea. The rivers flowing into such inland seas must necessarily carry various soluble salts, and these accumulate and ultimately crystallise out on the banks, or, if the lake becomes dry at any particular season of the year, they will form a crystalline deposit upon the surface of the bed of the lake. Dr. Wallace had no exact knowledge regarding the locality from which the salt deposits had been obtained, but he understood that they had been formed in the way just mentioned. The following are the analyses of four examples of the lake deposits : The chief point of interest to chemists in the analysis of the deposit was the condition in which the soda existed. It was found that the text-books generally stated that the Trona of Egypt, and other saline deposits, consisted of sesquicarbonate of soda, but Dr. Wallace's analyses showed that the neutral and sesqui-carbonate were associated in very nearly equal quantities; and it appeared, likewise, that, under the circumstances in which the deposits were formed, a compound of soda was formed that contained very nearly 4 equivs. of soda to 5 equivs. of carbonic anhydride. In no case had Dr. Wallace found the soda and carbonic anhydride present in the proportions necessary to form either the neutral or the sesqui-carbonate. Some chemists who had examined somewhat similar deposits had given the soda entirely as sesquicarbonate, others had given it as neutral carbonate, but a few had given analyses corresponding with those of the author. OBITUARY. JUSTUS LIEBIG. JUSTUS LIEBIG was born in the small German town of Darmstadt, on May 13, 1803, and educated in Bonn and Erlangen. He was originally intended for a pharmaceutist, but having found the means of visiting Paris, and passing some time in the laboratories of the great French chemists who flourished in the year 1823, and, having achieved a success as a chemist, he was at once enrolled by Humboldt in the ranks of the German professoriat, being in 1826 nominated Professor in Ordinary in the University of Giessen, after having for the two preceding years held office as Extraordinary Professor in the same university. Liebig began to publish very early. In the Annales de Chimie et de Physique for the year 1823, tome xxiv., p. 294, there is a paper entitled "Mémoire sur l'Argent et le Mercure Fulminans, par le Dr. Justus Liebig." About the same period there is also a note by Dr. Liebig, "Sur une Couleur Verte," which is an account of some observations on the making of arsenite of copper. It appears, however, that there were some publications of still earlier date, inasmuch as he refers to his own work in Buchner and Kasner's journal. The first publication, however, which excited attention was the one on the fulminates, which was first mentioned: Analyses of fulminate of mercury and fulminate of silver, and the preparation of most of the other fulminates, together with their analyses. We can understand that Humboldt was struck with the young chemist's ability who had accomplished such a task. In his professorship at Giessen, Liebig displayed the greatest activity, and gathered around him a knot of men whose names are household words among chemists. It was in Liebig's hands that ultimate organic analysis assumed the importance which it has acquired; and it was mainly owing to him that it was so popularised among chemists as to become one of the commonest resources of the laboratory. In Poggendorff's Annalen for the year 1831 may be read Liebig's own account of his improvements in the management of a combustion and in the apparatus. The following passage, which is exquisitely pithy and exquisitely modest, winds up the description:"In this apparatus there is nothing new but its simplicity and thorough trustworthiness."* The paper is a study of chemical method, and might be read with advantage by chemists living in the year 1873. We must, says Liebig, separate the determination of nitrogen from the determination of carbon, and make two distinct and independent analyses. We must have a method which admits of operating on 3 or 4 grms. of substances which are poor in carbon, and on to I grm. of substances which are rich in carbon. Liebig chose to weigh the carbonic acid instead of to measure it. In 1831 the measurement of gases was a matter of much greater difficulty than it is to-day, and the advantage gained at that period, by making the common combustion not to involve a gaseous measurement, was more striking than it is at present. Still, even to-day, there would be no gain in the substitution of measurements of carbonic acid for weighings of it, and the belief which some chemists entertain, that there would be, has its origin only in mental confusion and want of appreciation of the practical conditions under which analyses are accomplished and limited. Much of that which is best established and most familiar to us in organic chemistry is the work of Liebig, and was accomplished long ago. The constitution of chemical history of benzoic acid was made out by Liebig and Wöhler. Hippuric acid was explored by Liebig. Aldehyde, which previously bore the name "light oxygen ether," and was known only in a very impure condition, "An diesem Apparate ist nichts neu als seine Einfachheit und die vollkommene Zuverlässigkeit, welche er gewähst. was first rendered intelligible by him. Tyrosine, sarcosine, and creatinine, which are derived from flesh, are his discoveries. Though not the originator of the theory of compound radicals, he was one of its most powerful supporters, and contributed much of that which has proved to be most enduring in it. The theory of the existence of the radical ethyl is Liebig's, and the splendid investigation which led its authors to speak of the radical benzoyl was conjointly Liebig's and Wöhler's. The application of chemistry to agriculture, and to many of the wants of daily life, received so powerful an impulse from Liebig, that the popular mind has taken him for the representative of the science in its application to practical purposes. So great, indeed, has his fame become as a technologist, that writers in English newspapers have overlooked the fact that he was one of the greatest chemists of the century. Liebig left Giessen in the year 1852, and went to Munich, where he became Professor of Chemistry in the University and President of the Academy of Sciences. In 1845 he had been created a Baron. He died at Munich on the 18th of this month. DR. H. BENCE JONES. WE have to announce the death, on the 20th inst., after a long, and latterly, severe illness, of Dr. Bence Jones, the Secretary to the Royal Institution. Dr. Jones was a distinguished chemist; among his contributions to the adLectures "On Matter and Force," " Animal Chemistry in vancement of science may be mentioned his Croonian relation to Stomach and Renal Diseases," "Lectures on Pathology and Therapeutics," &c. His treatise on the early history of the Royal Institution, and his valuable biography of Faraday, are amongst the latest of his works. In our issue of March 21st, we announced the fact of a movement being set on foot to get up a testimonial to Dr. Jones, which, in agreement with his own wishes, will take the form of a bust to be placed in the Royal Institution. CORRESPONDENCE. MANUFACTURE OF SULPHURIC ACID. To the Editor of the Chemical News. SIR,-In reply to Dr. Lünge's observations on the above subject (CHEMICAL NEWS, vol. xxvii., p. 163), I beg to inform him, so far as his personal remarks are concerned, that Messrs. Allhusen's is not the only manufactory in which I have had experience in the manufacture of sulphuric acid, as I have had the advantage of being for a number of years engaged in many parts of both Great Britain and Ireland in the erection of such plant, and in some instances starting it to work; and that the acid plant with Glover towers, to which he refers as my knowing nothing about, was erected from plans prepared exclusively by myself, and the principal erections put up under my personal superintendence. I agree with him as to the ease with which chambers worked with Glover towers can be started by the use of an quantity of nitre," but contend that those worked on that system require this "extra quantity" much longer than the others. This at first sight may appear trifling, but in reality is very serious, when from 10 to 12 per cent of nitre on the sulphur charged has to be used for days in place of from 3 to 4 per cent. extra I still admire the rule-of-three where it can be applied with advantage, but in the case as shown by me it gives erroneous results, and therefore is no guide at all. The correct estimation of the nitrous compounds in the acid is a problem which has not yet been satisfactorily solved, and I, with your readers, will be happy to have the method NEWS from which Dr. Lünge and his friends derive such great comfort in keeping their chambers in good working order. I would also take this opportunity of pointing out a typographical error. In vol. xxvii., p. 137, twenty-seventh line from bottom, the figures 52.947 should be read as a whole number.-I am, &c., JAMES MCCULLOCH. PURIFYING CAUSTIC SODA. To the Editor of the Chemical News. SIR,-The mode of purifying caustic soda described by Dr. Lünge to the Newcastle-upon-Tyne Society, and consisting in blowing air into the soda when in the dry fusion state, is by no means new. I invented and carrried out into working order the same process in 1865, since which time it has been in constant use at these works under my superintendence. I noticed, at the time Mr. Helbig's specification was published in this country, the most remarkable similarity to my method, even to the caoutchouc tube. I have used the term "my method" for convenience only, as in fact the method was patented in 1860 by W. Ralston, of Keele, Newcastle-under-Lyne, dated November 22, printed in " Repertory of Patent Inventions," June 1, 1861, page 496. This latter, and to me disagreeable, fact I only discovered when about to patent the invention myself. That the method has merits is, I think, being shown by the fact of a considerable portion of the trade adopting it. Will you here allow me to correct an error which has crept into my previous letter, and which considerably alters the sense of the concluding paragraph. A single letter only has been left out. What I intended saying was that the bichromate method of estimating tin was in use in "this" (i.e., Ardwick Bridge Chemical Works) laboratory, not "his," i.e., Dr. Penny's laboratory, as I am made to say, in the early part of 1850.-I remain, &c., Ardwick Bridge Chemical Works, Manchester. MISCELLANEOUS. PETER HART. Appointment of Analyst for Sheffield.-At a meeting of the Sheffield Town Council held on the 9th inst., Mr. Alfred H. Allen, F.C.S., was elected Public Analyst for the borough by 39 votes to 13. The salary is £100 per annum. Mr. Allen is Lecturer on Chemistry at the Sheffield School of Medicine, and has given considerable attention to the detection of adulterations. Royal Institution of Great Britain. The following are the lectures to be delivered at this Institution, each lecture commencing at three o'clock:-E. Dannreuther, Esq. (three lectures), "On the Development of Modern Music in connection with the Drama, with Illustrations on the Pianoforte ;" on Tuesdays, April 22, 29, and May 6. J. H. Parker, Esq., C.B. (four lectures), "On the Evidence for the Traditional History of Rome from Existing Architectural Remains;" on Tuesdays, May 13, 20, 27, and June 3. Professor Tyndall, LL.D., F.R.S. (six lectures), "On Light;" on Thursdays, April 24 to June 5. Professor Odling, M.A., F.R.S. (four lectures), "On Ŏzone;" on Saturdays, April 26 to May 17. John Morley, Esq. (three lectures), "On the Limits of the Historic Method;" on Saturdays, May 24, 31, and June 7. To the Friday Evening Meetings, Members and their friends only are, admitted; the discourses will probably be as follows:April 25th, Professor Flower, F.R.S., "On Palæontological Evidence of Gradual Modification of Animal Forms;" May 2, Professor J. Emerson Reynolds, M.D., "On New Alcohols from Flint and Quartz;" May 9, M. E. Grant Duff, Esq., M.P., "A Fortnight in Asia Minor;" May 16, Professor Sidney Colvin, M.A., " On the Limits of Certainty in Taste, or in Artistic Judgment;" May 23, W. Spottiswoode, Esq., M.A., LL.D., Treas. R.S. and R.I., "On Spectra of Polarised Light;" May 30, the Earl of Rosse, D.C.L., F.R.S., M.R.I., "On the Radiation of Heat from the Moon, the Law of its Absorption by our Atmosphere, and its Variation in Amount with her Phases;" June 6, Professor Odling, M.A., F.R.S. Metropolitan Gas Supply.-Dr. Letheby, the Chief Gas Examiner appointed by the Board of Trade, has recently reported to the Corporation of London and the supplied by the Chartered, the Imperial, and the South Metropolitan Board of Works on the quality of the gas Metropolitan Gas Companies during the last three months. Dr. Letheby states that the average illuminating power of the Chartered Company's gas at the several testing places has been as follows:-At Beckton, North Woolwich, 17.22 candles; at Friendly Place, Mile End, 17.12 candles; 17:41 standard sperm candles; at Cannon Street, City, and at Arundel Street, Haymarket, 1678 candles. The gas of the Imperial Company has had an illuminating 16.07 candles at Camden Street, Camden Town; and power of 17.30 candles at Carlisle Square, Chelsea; 1563 candles at Graham Road, Dalston. The average power of the South Metropolitan gas has been 15.79 Company has been equal to 24'99 candles. As regards candles; and the power of the cannel gas of the Chartered Purity, Dr. Letheby reports that with one exception the gas at all the testing places has been constantly free from sulphur in the gas of the several companies has been as sulphuretted hydrogen, and that the average amount of follows:-1176 grains per 100 cubic feet in the Beckton Gas, 9'42 grains in that at Friendly Place, 15:42 grains at Cannon Street, 18:02 grains at Arundel Street, and 16.12 contained 32'11 grains per 100 cubic feet at Carlisle Square, grains at Millbank. The gas of the Imperial Company 2946 grains at Camden Street, and 30:47 grains at Graham Road. The average amount of sulphur in the gas of the South Metropolitan Company was 3611 grains per 100 cubic feet. With respect to this impurity, the referees have notified in their recent instructions for the gas examiners that the maximum amount of sulphur allowable in the gas of the several companies shall be 20 grains per 100 cubic feet of gas. This applies at the present time to the gas made at Beckton and Bow, and will apply to the gas made at other works after the 30th of June next. The amount of ammonia in the gas has not in any case exceeded 2 grains per 100 cubic feet of gas, and has averaged from 0'02 of a grain to 0'56. Anthracene Blue.-A few years since aniline was the great source of new and beautiful colours. Now that every possible shade of colour, surpassing in number and beauty the hues of the rainbow, have been produced from aniline, the chemist has taken up the study of anthracene and alizarine, also coal-tar products. While preparing artificial alizarine from anthracene, Springmühl has obtained a by-product, from which he has made a beautiful blue colour, superior in some respects to any of the aniline blues. The process by which it was prepared he keeps a secret. Dried in vacuo, it is a blue powder with a few little crystals. In this it differs from the aniline dyes, which are one colour when dry, another when in solution. When pure hot water is poured over anthracene blue it mostly dissolves, but leaves a little insoluble residue. The addition of an alkali destroys its colour, which is restored, however, by an acid. The strongest mineral acids are unable to destroy its colour, but rather heightens its tone. Unlike aniline dyes, it is insoluble in alcohol and ether. Experiments show that it withstands the action of light better than aniline blue. Unfortunately, it is at present very expensive, for Springmühl obtained but 25 grains of anthracene blue from 25,000 grains of anthracene, which makes it cost about 3000 dols. per pound at present. A cheaper method of making it is certainly desirable.-American Artizan. CHEMICAL NOTICES FROM FOREIGN SOURCES. Under this heading will be found an encyclopædic list of chemical papers published abroad during the past week, with abstracts of all susceptible of advantageous abridgment. The two halfyearly volumes of the CHEMICAL NEWS, with their copious indices, will, therefore, be equivalent to an English edition of the "Jahresberichte." NEWS oxygen. A current of oxygen in the same conditions gave 7 milligrms. per litre. In further experiments the precaution was taken to remove any nitrogen compounds by passing the air through a solution of caustic potash. The results were unaltered. Hence oxygen, in the condition in which it exists in the air, is more readily transformed into ozone in the proportion of 3 to 1 than pure oxygen gas. Another theoretical conclusion deducible from the above experiments is, that ozone cannot be a combination of oxygen with itself. The combination of several atoms of oxygen to form ozone seems to me to be a hypothesis no longer capable of being sustained. Note on a Series of Artificial Gems Presented to the Academy. -Ch. Feil.-Fragments of pale rose-coloured matter fused by the aid of borax, and stated as composed of almost pure alumina, when illuminated by sunlight in the phosphoroscope, emitted a bright red emitted by the ruby. NOTE. All degrees of temperature are Centigrade, unless otherwise light, the spectrum of which differed little from that of the light expressed. Comptes Rendus Hebdomadaires des Séances de l'Academie des Becquerel on Electric Capillary Batteries and their Action.The principle of electro capillary action consists in a property of the moist sides of capillary spaces; in virtue of which they conduct electricity like solid conducting bodies, whence result currents which produce in these spaces metallic reductions and other chemical actions. Such an electro-capillary element consists of an eprouvette containing a solution of nitrate or sulphate of copper, into which passes a slittube containing a solution of monosulphide of sodium. Into this enters another tube closed at its lower end with a spiral roll of paper, and containing a saturated solution of nitrate or sulphate of copper. Into the closed tube is introduced a slip of copper connected with a thin sheet of the same metal enveloping the outside of the slit tube. The latter is thus in communication with the deposit of copper formed in the crack by electro-capillary action. A battery formed of such elements is useful for producing slow, constant action. In the second part of this memoir the author shows the electro-capillary actions produced when a precipitate moistened with water, or with a solution, is in contact with a sheet of metal, more or less oxidisable, placed between two plates of glass, and cemented on the edges to prevent, as far as possible, the evaporation of water and the entrance of air. All the chemical effects produced are due to the joint action of affinities and of electro-capillary currents springing from the oxidation of the metal. In operating upon a zinc plate with chromate of lead moistened with distilled water, there were formed bibasic chromate of lead, more or less crystalline, and chromate of zinc. Using iron in place of zinc, the result was still bibasic chromate of lead in acicular crystals, ferric oxide, magnetic oxide in brilliant scales, mixed with chromate of iron and oxide of lead. Crystalline double oxalate of potash and copper was formed in an apparatus consisting of a tube closed at one end with parchment-paper, and containing a saturated solution of nitrate of copper, and of a beaker filled with a solution of potassic oxalate, into which the tube was plunged. The double oxalate was found in crystals on the exterior side of the paper, whilst the tube contained nitrate of potash. These researches lead the author to examine the opinions of physicists and chemists on the nature of affinities. He sums up his observations as follows:-In the molecular changes and chemical transformations of bodies we find produced calorific, electric, and sometimes luminous effects, which become the causes of affinities; but are the forces which produce them derived from the same principle and mutually convertible? If the same effect is produced in bodies, is the sum of the calorific or electric action constant? It is not proved. Heat and light are probably due to a vibratory movement communicated to the particles of bodies, but nothing gives a distinct indication that this is also the case with electricity and magnetism. When bodies are heated their volume changes, and reciprocally when their volume is changed thermic effects result. When there is no alteration in the state of aggregation the duty executed is equivalent to the heat emitted or absorbed. When molecular changes take place, they correspond to the amount of heat absorbed or emitted. In chemical actions we observe also thermic effects, but they only indicate the consequence of complex results, such as the mutual approximation or separation of molecules, especial groupings, &c. As to the disengagement of electricity in the changes of the state of aggregation of bodies nothing is ascertained. When bodies are unequally heated, if they are liquid no thermo-electric effect is observed. If solid, and if the parts in contact differ in nature, such effects become sensible. Still they are not energetic, and cannot serve to measure the effects produced. With metals those which have the highest specific heat are electro-positive. In the chemical action due to electricity, contrary to what is the case with heat, the laws are more simple, for each equivalent of electricity decomposes an equivalent of a compound body submitted to its action. The electro-capillary actions due to the joint influence of electricity, affinity, and molecular attraction introduce a new element into the question. If it is possible in certain cases to measure chemical action by the calorific effects produced, nothing similar can be done with the two electricities set free under the same circumstances, as they follow all conductors present, and even the extremely minute films of moisture adhering to nonconductors in order to re-constitute the "neutral Auid." These recompositions, after producing electro-capillary currents, take part in chemical reactions, and complicate the question of affinities. It may be remarked, further, that in chemical reactions produced with the aid of heat, such as fusion, nothing proves that there may not be electro-capillary currents acting as chemical forces-a question which will be treated in a future memoir. Note on the Effects Produced by Electric Currents on Mercury Submerged in Different Solutions.-Th. du Moncel.A physical examination of the movements of mercury under the above circumstances. Note on the Solvent Action of Glycerine on the Metallic and Calcareous Oleates, and on Sulphate of Lime.-E. Asselin. -Pure glycerine free from lime, of the sp. gr. 1'114, dissolved o'71_per cent of iron soap, o'94 of magnesia soap, and 118 of lime soap. The metallic and earthy sub-soaps, which impregnates the fibre of wool in the process of combing, are easily emulsified by water mixed with glycerine. Sulphate of lime dissolves in glycerine to the extent of o'957 per cent, and the amount dissolved increases with the temperature. Action of Chloride of Chloracetyl upon Aniline and Toluidine.-D. Tommassi.-Aniline and toluidine, under the influence of the chloride of chloracetyl, exchange an atom of hydrogen for an atom of chloracetyl, and give rise to two new crystalline products-phenylchloracetamideC&H H and benzyl-chloracetamide C2H CIOJ H N The former compound forms fine crystalline needles in an aqueous solution. It fuses at 97° C., and sublimes at high temperatures. Ether and acetic acid dissolve it in the cold to a large extent. Sulphuric and hydrochloric acid dissolve it easily when hot. Boiling nitric acid converts it into a new nitrogenous compound not yet analysed. Benzyl-chloracetamide crystallises in prismatic needles, which sublime at 110°, and fuse at 1620. It is insoluble in cold, and very sparingly soluble in boiling water. Sulphuric and acetic acids dissolve it sparingly in the cold, but freely when hot. In hydrochloric acid it is insoluble. By nitric acid it is converted into a nitro derivative. Note on the Poisonous Effects of the Iodides of TetramethylAmmonium or Tetramyl-Ammonium.-M. Rabuteau.-A physiological investigation. The iodides above mentioned destroy animal life by paralysing the nerves of motion; and their effects are, therefore, completely analogous to those of Curere or Wourali. Revue Hebdomadaire de Chimie Scientifique et Industielle, This number contains no paper of any chemical interest. La Revue Scientifique de la France et de l'Etranger, Annalen der Chemie und Pharmacie, No. 3, March 24, 1873. This number contains the following original memoirs and papers :Studies on the Alkaloids contained in the Cinchona Barks. O. Hesse. This exhaustive monograph contains a most complete historical, pharmacognostical, and chemical resumé of all that relates to this subject. The essay, though not suited for abstraction, is an excellent quinologicai vade-mecum, and a valuable contribution to the literature on the cinchona alkaloids. On Aurine.-R. S. Dale and C. Schorlemmer.-After referring to the earliest discovery of aurine by Kolbe and Schmitt (1861), to the labours of these chemists, and also of Fresenius, the authors state that Fresenius's coralline and their aurine are not identical. They then proceed to detail first, the method of purification of the commercially made aurine, and next, quote the properties of this body in pure state. It is crystalline, soluble in alcohol, acetic and hydrochloric acids, fusion-point 220°; the aurine is also soluble in alkaline solutions which exhibit a brilliant fuchsia colour. Acids precipitate from these solutions a crystalline powder. Formula of pure aurine, CH10. The following combinations are further described:-Aurine-sulpho-dioxide, 2(C1H180g)SO2+51H2O; aurine-potassium-bisulphite, C21H10O3+KHSO1; aurine-ammonium-bisulphite; leukaurine, the product of the action of iron and acetic acid upon aurine, CHO; triacetyl-leukaurine, C21H1O(CHO); tribenzyl-leukaurine; coralline (Fresenius's). Aurine prepared from pure phenol differs from the aurine obtained |