once. CHEMICAL NEWS 217 Industrial Applications of the Phosphide of Cop-, the solution is very concentrated is clear, but is rendered per and of Phosphor Bronze.- MM. H. de Ruoiz, turbid by the addition of water. The precipitate, doubt. Montchal, and de Fontenay. The authors claim priority less an oxychloride, is only very slowly re-dissolved by in the preparation and use of phosphor bronze, of which dilute hydrochloric acid. Thus, if it be desired to remove they have cast several pieces of artillery at Douai from all the gallium contained in an insoluble product, it is prudent 1854 to 1856. They consider that phosphorus, even in to heat it with strong hydrochloric acid. Ifto a concentrated minute doses, when added to melted alloys containing solution of chloride of gallium there is added exactly so copper prevents oxidation. much hydrochloric acid that it may be diluted with water without turbidity, we obtain a liquid which precipitates No. 18, October 30, 1876. copiously on boiling, but grows clear again on cooling. A New Electric Lamp designed by M. P. Jablosch. A slightly acid solution of chloride of gallium, if dried at koif.-11. L. Denayrouze.---'The new source of light is a gentle heat, deposits crystalline needles or leaflets, composed of two pieces of charcoal nxed in a parallel which act strongly upon polarised light. Sulphate of galpunton at a little distance from each other, and separated water a clear solution, which becomes turbid in heat, and lium is not deliquescent. Like alum, it forms with cold by un insulating substance capable of wasting away at the same speed as the charcoal. When the electric cur grows bright on cooling. I have prepared gallium-alum Itnt Legins to pass the voltaic arc is formed between the by mixing solutions of the pure sulphates of ammonium tu uncovered extremities of the iwo charcuals. Tlie and gallium. If protected from airiospheric dust the nearest layer of the insulating matter melts, is volatilised, liquid remains clear, but on contact with a fragment of and slowly lays bare the two rods of charcoal just as the common alum it deposits voluminous and well-defined wax of a candle progressively uncovers its wick as the crystals of ammonio-gallic alum. The existence of this combustion is propagated downwards. The heat springing salt, therefore, is no longer doubtful. from the combustion of the charcoal is utilised for the On Terephthalic Aldehyd.-M. E. Grimaux.-Not fusion and volatilisation of the insulating mixture. The suitable for abstraction. composition of this latter may be varitd indefinitely, since Simultaneous Formation of Two Trioxyanthramost earthy matters may be employed. The simplest quinons, and the Synthesis of a New Isomer of Purmixture provisionally adopted consists of sand and purin.-M. A. Rosenstiehl.- This paper will be inserted powdered glass, which with an equal electric power gives in full. double the light of a regulator. The author has been able to divide the liget produced by a single source of the current. With a single Gramme machine of the common Bulletin de la Societe Chimique de Paris, make he has caused three sets of charcoals to burn at Nos. 6 and 7, October 5, 1876. Nitro- and Amido-Naphthyl Sulphurous Acids, Distribution of Magnetism on the Surface of Mag- and on their Derivatives (Part II.) — M. P. T. Clève.nets.-MM. Tréve ard Durassier.— The authors find that An examination of naphthionic acid, diazo-naphthionic the more highly steel is carburetted the more the mag- acid, and of the dichloro-naphthalin derived from naphnetism is condensed towards its extremities. On the con thionic acid. trary, the less it is carburetted the more the magnetism is Two New Modifications of Dichlorated Naphthaequally spread over its surface. lin.--M. P. T. lève.- These are d-dichloro-naphthalin, Circular Polarisation of Quartz.-J. L. Soret and E. i Col16C12; and e-dichloro-naphthalin, eC10116C12. Sarasin.-Not suitable for abstraction. Explanatory Note on the Atomic Theory.-M. E. Chemical Reactions of Gallium.-M. Lecoq de Bourgoin.---The few lines which follow are not designed Boisbaudran.-When I merely possessed a few milligrms. / to refute the new critical observations which have been of impure compounds of gallium I admitted, though not addressed to the author in relation to his memoir on without reserve (Comptes Rendus, December 6, 1875, atomicity. They are merely intended to rectify two or p. 1105), that the oxide of gallium is more soluble in three assertions which have been gratuitously ascribed to ammonia than is alumina. Recent experiments confirm him, and the authorship of which he refuses to admit. this opinion. Thus, a mixture of the chlorides of aluminium He has been made to say that all atomic formulæ spring and gallium having been repeatedly treated with an excess from the type-formulæ of Gerhardt. He has never put of ammonia, the first ammoniacal solution was found very forward such an opinion. It is imagined that he admits rich in gallium, and the last precipitate consisted exclus the atomic weights of simple bodies to be proportional to sively of alumina. A single precipitation with a large their gaseous densities. He has never said anything excess of ammonia suffices to yield on the one hand a salt similar, for the very simple reason that he no more of gallium poor in aluminium, and on the other, alumina i believes in atoms than in the atomic theory, even as percontaining little gallium. If a mixture of the chlorides of fected by M. J. A. Le Bel. aluminium and gallium is subjected to tractional precipi- Various Notes on Analytical Chemistry.-H. Pellet. tation with carbonate of soda the rays Ga u 417.0 and -Reserved for insertion in full. Ga ß 403-1 are most intense in the first product, and sub Ferrocyanide of Tetramethyl-ammonium.-M. L. sequently go on diminishing. Still we cannot, in this Barth. This compound is obtained by neutralising a manner, arrive at a satisfactory separation og gallium and solution of hydrate of tetramethyl-ammonium with hydro. aluminium. Carbonate of soda only precipitates indium ferrocyanic acid.—Deutsche. Chem. Ges. after gallium. It is to be remarked that according to a theory which regards gallium as an intermediate stage sium.-M. Skraup.-By the action of a mixture of CIO3K Action of Halogens upon Ferricyanide of Potasbetween aluminium and indium, the precipitation of the oxide of gallium ought to be intermediate between that and HCl upon a neutral solution of ferricyanide of potasof the oxide of indium and that of alumina, and not to sium, and by adding alcohol, the author obtained small precede them both, as observation shows. The chloride black drops, which ultimately became a black crystalline and sulphate of gallium, if slightly acid, are not precipi. This is doubtless the same body which Bong tated in the cold by acetate of ammonia, also feebly acid, obtained by the action of chloric acid upon ferrocyanide. but the same salts, if neutral, are rendered turbid. An --Deutsche Chem. Ges. excess of acetate of ammonia renders the liquid clea Compounds of Sulpho-Urea with the Metallic again, and in that case it no longer grows turbid on heatSalts.--M. R. Maley.--An examination of the compounds ing, unless a large excess of water be added. Chloride of of sulpho-urea with the zincic, stannous, and mercuric gallium is very soluble and deliquescent. After having chlorides, cadmic sulphate, and mercuric iodide.--Deutsche been dried it attracts moisture from the air and liquefies: Chem. Ges. a mass. 218 Chemical Notices from Foreign Sources. { CHEMICAL News, Nov. 17, 1876. LESSONS IN ELECTRICITY at the Royal OF OR THE Derivatives of Sulpho-Urea.-MM. Claus and Rim Now ready, in crown 8vo., with 58 Woodcuts, price 2s.6d., bach.-The authors describe the reaction of sulpho-urea and trichlor-acetic acid. . , , Substitution Derivatives of Oxide of Ethylen.-M. | F.R.S., Professor of Natural Philosophy in the Royal Institution of E. Demole. Great Britain. London; LONGMANS and CO. Researches on Ethyl- and Methyl-Oxamethan.0. Wallach and P. West.–These two papers do not admit Now ready, Third Edition, enlarged and revised, with 74 engravings; of useful condensation, Svo., 155. Tetra-Substituted Ureas.-M. W. Michler.-A pre A SYSTEMATIC HANDBOOK liminary notice. On Oxymercaptans.--R. Biedermann.-- The author is VOLUMETRIC ANALYSIS; engaged with attempts to introduce the group SH into phenol, and the group of into thiophenol. —Deutsche QUANTITATIVE ESTIMATION OF CHEMICAL SUBSTANCES Chem. Ges. BY MEASURE, APPLIED TO LIQUIDS, SOLIDS, AND GASES. On Gaulterylen.-R. Biedermann.-The author con. Adapted to the requirements of Pure Chemical Research, Patholofirms the view of Cahours that this compound is a terpen gical Chemistry, Pharmacy, Metallurgy, Manufacturing Chemistry, of the formula C10H16. Photography, &c., and for the Valuation of Substances used in Com merce, Agriculture, and the Arts. Action of Cyanide of Potassium upon Halogenated By FRANCIS SUTTON, F.C.S. Compounds.-MM. Claus and Beuttel.-Chloro-crotonic 1. and A. CHURCHILL, New Burlington Street. ether in an alcoholic solution is treated under pressure with cyanide of potassium. The products are two acids, Now ready, New Edition, 8vo., 75. 6d., one of which has received the name of the tricarballylic. CHEMIA COARTATA: -Deutsche Chem. Ges. OR, THE Key TO MODERN CHEMISTRY. Product of the Reaction of Potassium upon the By A. H. KOLLMYER, A.M., M.D., Succinate of Ethyl.-Ira Remsen.—This product, which Professor of Materia Medica and Therapeutics at Montreal. represents the ether of a disuccinic acid, has been further J. and A. CHURCHILL, New Burlington Street. examined by the author. XERCISES IN EXPERIMENTAL PHYSICS. By C. J. WOODWARD, B.Sc., and GEORGE SMITH, the derivatives of u-chloro-propionic ether. B.Sc. Part I. A, price 6d. ; Acoustics, Light, and Heat (Elementary Hydrazinic Compounds of the Fatty Series.-M. stage). Part II., price gd.; Magnetism and Electricity Elementary and advanced stages). E. Fischer. The compounds studied by the author are London: SIMPKIN, MARSHALL, and Co. nitroso-diethylen, nitroso-diglycolamidic acid, and nitrosopiperidin. There is also a paper by the same author on REFINED ANTHRACENE the “ Aromatic Hydrazinic Compounds." Aromatic Nitriles.-V. Merz and K. Schelnberger. COAL-TAR PRODUCTS. Nitriles are formed by the action of yellow prussiate upon the halogenous aromatic carbides. HENRY SCHOLEFIELD, Action of Aniline upon Nitrobenzol.—MM. Dechend Cleadon Chemical Works, Newcastle-on-Tyne. and Wichelhaus.--Already noticed. Amidated Acids.-J. W. Brühl.-An examination of EXE AND OTHER edachloro-nitro-benzol, hand_on, certain, Chloe: South London School of Pharmacy: 325, Ken inised Compounds.-M. A. Laubenheimer. -Not adapted for condensation. Extraction of Sulphur from Pyrites.-P. W. Hofmann.-If sulphide of calcium-e.g., the vat-waste from alkali works-is heated to dull redness in a current of sulphurous acid gas, obtained by roasting pyrites, the latter is at first completely absorbed. Sulphur then distils over, and the sulphide is converted into sulphate, which may be anew reduced to sulphide by calcination in a current of coal-gas.—Deutsche Industrie Zeitung. On Aniline-Black.-M. Nietzki.-Reserved for insertion in full. On Pittacal.-M. C. Liebermann.-Reserved for inser. tion in full. Daily Lectures on the following subjects:- MATERIA MEDICA. PHARMACY CLASSICS. For all particulars, enclose a stamped envelope to the Secretary, Mr. W. BAXTER, at his ottice, Central Public Laboratory, Kennington Cross, London, S.E. COLLEGE of CHEMISTRY, in conjunction with the SCIENTIFIC DEPARTMENT of the ROYAL POLYTECHNIC INSTITUTION. Instruction and preparation in CHEMISTRY and the EXPERIMENTAL SCIENCES under the direction of Professor E. V. GARDNER, F.A.S., M.S.A. The Class Rooms are open from ii to 5 a.m. and from 7 to 10 p.m. daily. Especial facilities for persons preparing for Government and other examinations. Private Pupils will find every convenience. Analyses, Assays, and Practical Investigations connected with Patents, &c., conducted. Prospectuses and lull particulars on appiication to Prof. Gardner at Berner's College, 44, Berners-strett, W., or at the Royal Polytechnic Institution. BERNERS Les Mondes, Revue Hebdomadaire des Sciences, No. 7, October 19, 1876. Society of Public Analysts. We are informed on good authority that the Tieasurer of the Society of Public Analysts (Dr. Stevenson) has sent in his resignation and retired from the Society. MORRIS TANNENBAUM, 37, Fitzroy MEETINGS FOR THE WEEK. STREET, offers Jewellers, Mineralogists, Lapidaries, and specially Collectors of Rare Cut Gems (which he possesses in all existing kinds), large Collections of Fine Hyacinths in all Colours, Clear Spanish Topazes, Blue and Yellow Amethysts, Jargon, Olivine, Fossils, Fine Collections of Shells, Thousands of Indian Pebbles. Polished Agates, &c., Starstones and Catseyes, Garnets, Cape Rubies, Fine Slabs of Lapis Lazuli, Fine Emeralds in the Matrix, Fine Crystallised Rubies and Brazilian Topazes, and Thousands of Rare Opals. Specimens and for Cuttings. Orders effected to all parts of the world. SATURDAY, Nov. 18th.-Physical, 3. "On the Cohesion or Capillary Action of Films of Water, especially when } Repulsion Resulting from Radiation. NEWS. CHEMICAL News, 219 It is worthy of notice in these Tables that the attraction THE CHEMICAL by the incandescent spiral is only moderate in air of ordi. nary density. The attraction diminishes to a minimum between a tension of 50 millims. and 150 millims., then Vol. XXXIV. No. 887. rises as the pressure diminishes, until, at a tension of 1'15 millims., the attraction is nearly four times what it was in dense air. Above this exhaustion the attraction sud. denly drops and changes to repulsion, which at the best ON REPULSION RESULTING FROM vacuum I could get was nearly thirteen times stronger RADIATION.-PART II.* than the attraction in air. By WILLIAM CROOKES, F.R.S., &c. TABLE II. Tension of enclosed oscillation in millims. 100. EXPERIMENTS were first tried in air of normal den Temp. = 16° C. at end of 40" obsersity. The pump was then set to work, and observations Bar. = 772 millims. vation. were taken at different heights of the gauge. The differ 772'0 +0:460 ence between the height of the gauge and that of the 770'0 +0:540 barometer gave the tension of air in the apparatus in 7695 +0.570 millimetres of mercury; this is recorded in the first 769'0 +0:440 column of the following tables. The second column gives 769 0 +0:520 the greatest amplitude of the half oscillation of the pen 76990 +0'440 dulum in millimetres— the sign plus signifying attraction, 76900 +0:450 and minus repulsion. 565'0 +09560 Near the centre of Table I., in the second column, are 557'0 +0*540 five observations to which I have affixed no sign. When 472'0 +0.490 trying the experiments I thought that either I had mis 440'0 +0:550 taken the direction of impulse, or my assistant had com 369.0 +0:416 menced to count the make-and-break seconds wrongly, as 2130 +0:233 the movement seemed to be repulsion. Never having had 207'0 +0:130 repulsion at such a pressure before, I was not prepared 189.0 +0:180 for it; and fearing there might be an error, left the sign 173'0 +0:140 queried. Another series of observations were taken to 16440 to'100 re-examine this point; they are given in Table II. 162'0 -O100 142'0 -O'120 132'0 -0'130 Tension of enclosed 127'0 -o'ogo 105'0 -0'140 Temp. = 16° C. at end of 40" obser 102'0 +0.083 73'0 -0*130 боо -Oʻ123 56.0 -0.136 51'0 –0'030 41'0 +0*150 33'5 +0*170 32'0 +0:106 23'0 +0'110 22'0 to'o80 16:1 +0'170 16'0 +0*140 140'00 7'I +0'380 6'0 +0'293 3:9 +0.610 70050 1'9 +0.880 54'00 I'2 +0.755 o'9 +0*340 097 -0'740 - 1700 0'3 -3.800 -5'080 Oo - 5.680 -0.05 -6°320 ti'oo The last figure in the first column requires explanation. All the others are obtained by subtracting the height of 1'15 +1°72 the guage from that of the barometer, and are positive. 0*75 +1470 At the highest rarefactions, however. I get the gauge 0.65 +1:46 about 0'05 millim. above the barometer (85, note); the sign, therefore, becomes negative. Table II. agrees in the main with Table I. changes to repulsion at pressures corresponding to those queried in Table I.; the repulsion, though slight, was -0'05 -5.90 unmistakable. At 102 millims. pressure the observation has a positive sign. This looks ke an error ; but as it is * A Paper communicated to the Royal Society, March 20, 1875. so recorded in my notebook, and as I was at that time From the Philosophical Transactions of the Royal Society of London vol. clxv., pt. 2. specially looking for repulsions, I do not feel justified in 0'07 ? 0'03 ? 0'02 ? 0:6 The sign 42.8 arc. ON THE CHEMICAL News, 220 Development of the Chemical Arts. { , 1876. altering it. What I have called the neutral point, or the Chromium 29:8 point where attraction changes to repulsion, is in this Arsenic 42-7 series lower than in the former. There it occurred at a Oxygen (by diff.) 2785 tension of about o‘3 millim. of mercury; here at about 0.8. Neither does the previous attraction attain such strength, although the ultimate repulsion is more intense. This agrees very closely with the formula CrAsO 3, The agreement is, however, sufficiently satisfactory, con- which would be-sidering the faulty method of measurement. Chromium 30'0 There are many errors almost inseparable from this form Arsenic of apparatus. The making and breaking contact by hand is not sufficiently certain, and hesitation for a fraction of Oxygen 27'2 a second would seriously affect the ultimate amplitude of I tried making and breaking by clockwork, also by a seconds' pendulum, but there were difficulties in each I think we may reasonably conclude that the powder is plan. an arsenite of chromium. I am now engaged in preparing Owing to the mode of suspension, there was uncertainty a further quantity of it (having only prepared a smali as to the length of the pendulum. I tried to make it the quantity on the former occasion) with a view to further right length to beat seconds in vacuo. Assuming that I investigation. had succeeded in this, the pendulum would have executed Chemical Laboratory, Catholic University College, fewer vibrations in the 40 seconds when oscillating in air, Wright's Lane, Kensington. and consequently I should not have got the full benefit from the making and breaking contact, supposing these were accurately timed to seconds. REPORT The battery-power varied, being stronger at the commencement, and gradually declining towards the end of the experiment ; and even were the battery to remain DEVELOPMENT OF THE CHEMICAL ARTS constant, the spiral became much hotter, owing to the DURING THE LAST TEN YEARS.* removal of the air from the apparatus, ranging from a bright red heat in air to a full white heat in vacuo. By Dr. A. W. HOFMANN. Owing to the height of the centre of suspension of the (Continued from p. 216.) pendulum from the stand of the apparatus, the slightest deviation from the perpendicular made an appreciable difference in the distance of the weight from the spiral, Chlorine, Bromine, Iodine, and Fluorine. and thereby increased or diminished the effect of radiation. By Dr. E. Mylius, of Ludwigshafen. Thus the tread of a person across the floor of the labora. G. LANGBEin reports that he has introduced another protory, or the passage of a cart along the street, would cess in the works of the firm tildemeister and Co., as cause the image of the edge of the magnesium weight the process of Thiercelin disregards the iodine existing as apparently to move from the cross wires in the telescope. sodium iodide along with the iodic acid. This does not, Many of these sources of error could have been re- however, apply to the more recent method of Thiercelin, moved; bnt in the meantime having devised a form of since hydriodic acid is very readily decomposed by nitrous apparatus which seemed capable of giving much more acid. accurate results, I ceased experimenting with the The compounds of iodine find little application in manupendulum. factures, and are therefore merely produced on a small Before proceeding to describe the apparatus subse-scale. Proposals for improved methods of preparation are quently employed, ỉ may mention that a candle flame therefore of limited interest and require but a very brief brought within a few inches of the magnesium weight, or notice. its image focused on the weight and alternately obscured For the preparation of the iodides of potassium, and exposed by a piece of card at intervals of one second, calcium, and lithium Liebigt proposes to form a solution will soon set the pendulum in vibration when the vacuum of phosphoric and hydriodic acids by the reaction of amor. is very good. A ray of sunlight allowed to fall once on phous phosphorus, iodine, and water, and to saturate the the pendulum immediately sets its swinging. The acid liquid with caustic baryta. Phosphate of baryta is pendulum apparatus above described was exhibited, and precipitated and iodide of barium remains in solution, experiments shown with it, at the Royal Society, April from which (Pettenkofer) any desired iodide may be ob22nd, 1874, and also before the Physical Society," June tained by precipitation by means of a sulphate. In pre20th, 1874. paring calcic iodide the acid may be neutralised with (To be continued). milk of lime. Rud. Wagner: proposes to form the iodides by decom. posing sulphites with iodine. For this purpose the sulphite of barium is particularly adapted, which is COMPOUND OF CHROMIUM ARSENIC. diffused in water and treated with iodine, yielding sulphate of baryta, marketable as blanc fixe and iodide of barium. By R. H. C. NEVILE. But the process already in use of reducing sulphate of barium and decomposing the sulphide thus obtained with I THINK that a short notice of a compound of which I iodine is evidently simpler. have seen no mention in any book may not be without Fluorine.-Fluorine, which it was hoped would, in its interest to your readers. On pouring á hot and strong compounds, prove capable of important industrial applicasolution of pure chromic acid into a hot and saturated (or tions, has in no manner fulfilled the expectations enternearly so) solucion of arsenious acid, the liquid in the tained. Many attempts made with this view down to the first instance becomes green, still remaining transparent. year 1867 have proved fruitless. Amongst such we may If, however, it be kept at nearly the boiling point it remember the proposal of Weldon || to prepare soda by gradually becomes opaque by reflected, but transparent by * “ Berichte über die Entwickelung der Chemischen Industr'e transmitted, light, and finally a dark green powder falls. Während des Letzten Jahrzehends." On washing this powder thoroughly and analysing it, it + Liebig, Ann. Chem. Pharm., cxxi., 222. Wagner Jahresber., 1862, was found to have the following composition : Wagner, Bayer, Kunst, &c., Gewerbbl., 1862, 235. Wagner Jahresber., 1862, 261. * Phil. Mag. August, 1874. ! Weldon, Dingi. Pol. Journ., clxxxii., 228. 257 a ,} Nov. 24, 1876. Calculation for Analyses of Superphosphates, &c. 221 means of hydrofluoric acid. A solution of sulphate of required result (with great accuracy) in a far shorter time soda was decomposed by means of hydrofluoric acid, than when the ordinary method is adopted; the chances obtained either by heating a mixture of magnesium of a mistake are also greatly reduced. For every fraction fluoride and sulphuric acid, or by decomposing sodium of a grm.of the various precipitates obtained, the substance fluoride with superheated steam. The sulphate of soda sought may at once be found by looking under its number was thus to be resolved into bisulphate, which remains in in the table, and removing the decimal point as the case solution, and natrium fluoride, which separates out. This may require. An example is given, which I trust will at latter salt is either converted into hydrofluoric acid and once make the matter quite clear, and show the shortness hydrate of soda by means of superheated steam or con- of the method :verted into hydrate of soda and magnesium fluoride by the addition of magnesia. The magnesia necessary for this Calculations for a Superphosphate. purpose is obtained by heating common salt with Epsom P20, soluble in cold water, existing as CaH4P208. salt (MgSO4+H2O), forming magnesia, hydrochloric acid, and sulphate of soda, which latter, as above mentioned, I grm. gave oʻ1995 Mg2P20,= 19*95 per cent Mg2P207. serves for the preparation of the sulphate of soda. The Required, the per cent of CaH4P208:-magnesium fluoride formed by decomposing the sodium 10'00 10*5405000 fluoride with magnesia serves for the preparation of 9:00 9:4864500 hydrofluoric acid, being heated along with the acid sul. 0990 o'9486450 phate of soda obtained in the first operation, and thus 0'05 0-0527025 converted into sulphates of magnesia and soda and hydrofuoric acid, the latter being again applicable for the 19'95 21.0282975 CaH4P208. decomposition of sulphate of soda. Thus all the materials required for the manufacture of soda are regenerated, and Required, water lost by the CaH4P208 on ignition, to be merely the common salt and the fuel are consumed. subtracted from the total loss on ignition, which would According to the inventor the cost of plant, fuel, &c., is otherwise be counted as “organic matter and combined smaller than in Le Blanc's process. As a shorter process water":Weldon suggests to convert common salt at a red heat 1.6216000 into sulphate of soda and hydrochloric acid by means of 9'00 I'4594400 bisulphate of soda. The sulphate of soda is then dis o'90 Oʻ1459440 solved in water, and split up into sodium fuoride and 0'05 0'0081080 bisulphate of soda by means of hydrofluoric acid, and from the sodium fluoride the hydrofluoric acid is recovered 19'95 3*2350920 OH2 in 19895 CaH4P208. by treatment with superheated steam, hydrate of soda being the final product of this series of reactions. Not Insoluble P205 existing as CazP208, obtained by subwithstanding the alleged remunerative nature of these tracting the soluble P205 (Mg2P207) from the total quanprocesses neither of them has found its way into practice. tity, i.e., the portion dissolved in Hći. (To be continued.) I'1045 grms. gave 0'2595 Mg2P207. 19.95 soluble 10'00 3'00 ON THE 3:54 % insoluble CALCULATION OF THE RESULTS OBTAINED Required the per cent of Ca3P208:FROM THE ANALYSES OF SUPERPHOSPHATES, 4:1891700 MANURES, &c. 0:50 0.6981950 0'04 By R: C. WOODCOCK, F.C.S., 0'0558556 Royal Agricultural College, Cirencester. 3:54 4:9432206 CazP208. I'1045 grms. gave oʻ508 CaCO3. There are probably few substances met with during the ordinary course of commercial analyses that require a Required the per cent of CaS04:more tedious set of calculations than a superphosphate. I'1045: 0-508 :: 100: x=45'99 per cent CaCO3. Having frequently to do these calculations, I was induced CaCO3 to be deducted from the total quantity, for to make up the following set of tables, which give the I Ca contained in CaH P208: I. 2. Found. 3. 6. 9. Mg2P207 CaH4P208 1'05405 2·10810 3:16215 4'21620 5'27025 6°32430 7837835 8:43240 9.48645 Do. Ca3P208 I'39639 2.79278 4:18917 558556 6.98195 8.37834 9*77473 II'17112 12*56751 0945045 o'900go I'35135 1.80180 2'25225 2'70270 3:15315 3.60360 4'05405 Do. CaCO3 for! 6*75675 I'35135 2.70270 4'05405 5.40540 8.10810 CazP208 9.45945 10:81080 12'16215 OH, in Do. ! 0:81080 0·16216 0:32432 0.48648 0.64864 O'97296 I'13512 I'29728 I'45944 P205 0:63964 1'27928 1'91892 2955856 3:19820 3.83784 4'47748 5'11712 5'75676 9.88734 11'53523 13.18312 14:83101 3:52110 4'22532 4'92954 5:63376 6°33798 CaH4P208 / 0*70422 1040844 2·11266 2.81688 Do. CaCO3 for CazP208 Do. OH2 in 1•26760 1952112 1'77464 2'02816 2'28168 Calī,P208 | 0-25352 0·50704 0·76056 1'01408 CaCO3 1'36000 2.72000 4'08000 5'44000 6.80000 8:16000 9:52000 10:88000 12'24000 PtCI,2KCI K20 0'19287 0'38574 0.57861 0*77148 0096435 I'15722 I'35009 1'54296 1•73583 PCI 2Amci Am2SO4 0'29583 0859166 0.88749 I'18332 1'47915 1'77498 2'07081 2-36664 2.66247 P205 | 2-11268 4:22536 6-33804 8:45072 10°56340 12-67608 14°78876 16:90144 19-01412 CaSO4 |