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pose, and the bromide of silver, likewise spe- but is dissolved by ether. The nature of the cially prepared, for comparison. The mean of hydrocarbon oil may be determined after it a series of eight experiments gave 112:31 as the has been isolated, by observing its density, atomic weight of the metal. This determina- taste, smell, behavior with acids, and other tion is regarded as bearing against the validity qualities. of the hypothesis of Prout, that all atomic Professor G. Lunge, of Zürich, has perfected weights are multiples of that of hydrogen. and described a simple and inexpensive process

New PROCESSES.—Mr. Alfred H. Allen has in- for procuring pure naphthalen that will not dicated some valuable simple tests for the pres- discolor. Presuming that the discoloration of ence of hydrocarbon oils as adulterations in naphthalen is analogous to that of phenol, he animal and vegetable oils. The methods for sought to remove the agent which caused it by the detection of these oils are based on the oxidation. For this purpose he added an oxidensity of the sample, the lower flashing and dizing agent in the ordinary chemical washing boiling points, the fluorescent character of the of naphthalen, using manganese dioxide, with oils produced from petroleum, bituminous complete success. Other oxidizing agents might shale, and rosin, and the incomplete saponifi- be substituted for manganese dioxide, but a cation of the oil by alkalies. The taste of the cheaper one can hardly be obtained. Naphthaoil and its odor on being heated are also use- len prepared by this process has kept its pure ful indications. If undoubtedly fluorescent, an white color much longer than the chemically oil certainly contains a mixture of some hydro- pure " naphthalen made by the secret process carbon, but the converse is not strictly true, as of the manufacturers. the fluorescence of some varieties of mineral A patent has been taken out by M. Closson, oil can be destroyed by chemical treatment, of Paris, for a cheap and expeditious method and in other cases fluorescence is wanting. of obtaining magnesia from magnesium chloThe greater number of hydrocarbon oils em- ride. The crude lye of magnesium chloride is ployed for lubricating purposes are, however, treated with burned dolomite, or magnesian strongly fluorescent, and the remainder usually limestone, when the chlorine of the lye combecome so on treatment with an equal measure bines with the lime of the dolomite, so that if of strong sulphuric acid. If strongly marked, the latter is pure a magnesia of from 98 to 994 the fluorescence of a hydrocarbon oil may be per cent standard can be easily made on a large observed in presence of a very large proportion scale. The magnesia bricks prepared by this of fixed oil, but, if any doubt exist, the hydro- process at Leopoldshall resist even the flame of carbon oil may be isolated. The fluorescence the oxyhydrogen-blast. The cost is fifteen may be seen by holding a test-tube filled with shillings à ton. Sulphate of lime is obtained the oil in a vertical position in front of a win- as a by-product of the process through the use dow, when a bluish bloom" will be perceived of calcium chloride to remove the magnesium on looking at the sides of the tube from above. sulphate that is present in the magnesium chloA glass rod dipped in the oil and laid on a ride, and is used by paper-makers under the table in front of the window so that the oily end name of pearl-hardening. The value of the shall be projected in the view against the dark new process in its bearing on the manufacture background of the floor, or a piece of black of fire-proof furnace-linings, crucibles, etc., is marble or smoked glass rubbed with a streak very great. of oil and held horizontally before a window, Herr A. Wagner recommends the following will make a very slight fluorescence, readily process, which has proved very satisfactory perceptible. Turbid oil should be filtered, to for the limestone waters of Munich, for the get out the minute particles that might, by determination of the organic matter in water. reflection, give an appearance of fluorescence. After the determination of all the other conDilution with ether, to which a little mineral stituents of the water, he evaporates suitable oil imparts a strong blue fluorescence, gives an quantities to dryness and separates the dry excellent test. The hydrocarbon oil may be residue by means of distilled water into an driven off by heating it if its boiling-point is insoluble and a soluble portion, the latter of comparatively low, but may be better removed which contains the chief bulk of the organic and the quantity of it measured by saponifying bodies. In the insoluble portion, which in the it, and washing the solution of the soap with waters he has to deal with consists almost enether. The hydrocarbon may, in this case, be tirely of calcium and magnesium carbonates, recovered pure by separating the ethereal layer he determines the organic matter by igniting and evaporating it at or below a steam-heat. a dried specimen in a platinum crucible and A good alkaline preparation for this purpose treating subsequently with ammonium carboncan be made by dissolving caustic potash in ate in the customary manner. The portion methylated spirit. The washing with ether soluble in water, if nitrates are absent or are should be repeated several times. The etber- present only in a quantity too small to be deprocess is, however, not applicable to sperma- termined, is dried after evaporation in a platceti and the waxes, on account of the large inum capsule, weighed, heated to a very low quantities--so small in the other fats that it redness, and weighed again. If nitrates are need not be taken into account-of matter they present in larger quantities, so that the existcontain that is not acted upon by the alkalies ing organic matter would not suffice to con

vert the nitrates into carbonates, he adds to the arsenic as arsenious acid, is formed. This the soluble portion, after drying and weighing, is extracted with water till it has been made a little pure solution of sugar, evaporates to to give up its arsenic, and the reddish-brown dryness, and heats the platinum capsule gradu- fluid containing some organic matter is evapally and by piecemeal with a very small gas- orated to dryness. The residue is dissolved at flame, so that no deflagration may happen. a gentle heat with a definite quantity of dilute After prolonged but very gentle ignition, the sulphuric acid, and introduced to a Marsh's apsugar-charcoal is found burned away, when paratus for the decomposition of arseniuretted the residue is moistened with water containing hydrogen by artificial heat, to which a Buncarbonic acid, and weighed again after drying. sen wash-bottle and a device for graduating The loss of weight in this case expresses the the admission of the fluid have been added. weight of the organic substances and the dif- The resultant gas having been dried in a ference between the equivalent of the nitric chloride of calcium tube, is passed through a acid which was present and of the carbonic red-hot glass tube. Not a trace of arsenic acid which has taken its place. This difference passes by if the cooled tube is of proper can be easily calculated from the quantity of length. The apparatus is then filled with the nitrates as previously ascertained, and must hydrogen generated by the sulphuric acid-zinc be deducted. This process is not absolutely process, and the glass tube, having been accurate, but Herr Wagner considers it more heated to redness, the arsenical solution in certain than others. Herr Wagner calls atten- concentrated form is mixed with sulphuric tion to the necessity, in experiments for deter- acid, and the mixture is slowly passed into a mining the solid residues, of protecting the separating funnel; then more and stronger platinum or porcelain capsule in which the acid is added, and the heat is kept up till the water is treated against the accumulation of a decomposition is wholly effected. The arsenic deposit from the gas-flame, through which a being collected in the form of a mirror of liability to error in weight is incurred. For metal, the tube is cut, at a safe distance from this purpose he uses a thin sheet of platinum, the mirror, and weighed. The arsenic is reinstead of the ordinary wire gauze, between moved by heating, and the tube is weighed the capsule and the flame.

again, when the difference gives the amount of Mr. Thomas Moore has published the follow- metallic arsenic. The method is capable of ing new process for the separation of nickel detecting as little as the one thousandth of a and cobalt from iron: Having removed any milligramme of the metal. In organic matters excess of free acid by evaporation, and dis- the experimenters have detected a millionth of solving the residue in water, add to the solu- a gramme in urine and in an extract from beef. tion a sufficient quantity of ammonic sulphate The experiments are claimed to show that the to form a double sulphate with the nickel and presence of organic matter in considerable cobalt present. Dilute to about 150 c. C., and quantity does not interfere with the recovery add a rather large excess of oxalic acid, and of the entire amount of arsenic. stir well. In case a precipitate form, more VEGETABLE ANALYSIS.-Professor Henry B. ammonic sulphate should be added until a Parsons, of Washington, D. C., has described clear solution is obtained. Add ammonic hy- & method for the more accurate analysis of droxide in considerable excess; stir, heat plants. His apparatus includes a worm of gently for a few minutes, and filter; wash block-tin pipe, suitably connected with a glass well with water containing ammonia; or di- percolator, within which is suspended a smaller lute to about 500 C. C., and, after allowing the tube, having a bottom of filtering-paper and precipitate to settle, withdraw a given portion fine, washed linen. The weighed sample of the of the clear upper stratum of liquid. This, finely-powdered herb is placed within this tube after a further addition of ammonic sulphate, for extraction. The solvent is introduced in a to lessen the resistance to the electric current, glass flask, tightly fitted to the outer percolator, is ready for electrolysis or any other method and is volatilized by the application of heat of estimating the nickel or cobalt.

through a water-bath.

A tared filter, preMessrs. R. H. Chittenden and H. H. Donald- pared by allowing fine asbestus, held in water, son, of the Sheffield Laboratory, Yale College, to settle on the perforated bottom of a platidescribe a process for the detection and de- num crucible, is also provided and connected termination of arsenic in organic bodies, which with the receiving-vessel, while this in turn is they recommend as very accurate, delicate, and connected with a Bunsen's pump. The air-dried simple. It is based upon Gauthier's process, specimen of the plant to be analyzed should be and somewhat resembles it, but requires for ground or beaten till all the particles will pass reagents only nitric acid, sulphurio acid, and through a sieve having from forty to sixty zinc. The organic matter is destroyed by meshes to the linear inch. A part of this successive oxidations with nitric and sulphuric should be further pulverized till it will pass acids, as in Gauthier's method, but at a much through a sieve having from eighty to one lower temperature. The suspected matter is hundred meshes to the linear inch. The finer then treated for fifteen minutes at 200° C., and part of the sample is employed in the immediate allowed to cool, when a hard, carbonaceous analysis, while the coarser part is reserved for residue, free from nitric acid, and containing the separation of those proximate principles

which 'may seem, from the analysis, to be fibrine, and a considerable quantity of precipiworthy of more extended investigation. The tated papaine. Alcohol precipitates from it amount of moisture is estimated by ascertain- crude papaine; this, after being washed in aling the loss of weight on drying a small por- cohol and ether, to remove fatty matters, is tion of the sample. The crude ash left after again dissolved in water. The precipitate from ignition is separable into the constituents that this solution is pure papaine, which, when puriare soluble in water; those that are insoluble fied by dialysis, las the composition of an alin water, but are soluble in dilute hydrochloric buminoid substance. Papaine, refined with the acid; and those which, insoluble in those sub- subacetate of lead, offers several distinctive stances, are soluble in sodic brydrate. The resi- characteristics, among which are: 1. It is very due still undissolved consists usually of a little soluble in water, dissolving like a gum; 2. The unconsumed carbon. The amount of nitrogen solution makes a lather with water; 3. The is determined by combustion with excess of solution becomes turbid in boiling, without cosoda-lime. Exposure of a part of the sample to agulating; when it is curdy it sometimes leaves the action of pure coal-tar benzole gives the an insoluble residue in water; left to stand, benzole extract, which may consist of volatile the solution becomes turbid after some days, oil reinovable by evaporation; alkaloids, glu- and a microscopic examination shows it to be cosides, and organic acids, soluble in water; filled with vibriones; 4. In the presence of a alkaloids, and possibly glucosides, soluble in saccharine liquid, papaine acts as an alcoholic dilute acids; chlorophyl and resins, soluble in ferment with an extraordinary energy and 80 per cent alcohol; and wax, fats, and fixed promptitude, but the digestive property may oils which do not yield to either of the solvents. be arrested by the application of benzoic or The part of the plant not dissolved by benzole salicylic acid. The most important property is further treated with absolute alcohol, and of papaine, and one which puts it in the rank afterward with other agents, as water, sub- of the most powerful digestive ferments, is its acetate of lead, and dilute hydrochloric acid, action on meats. One part of papaine will dias special tests. The part which remains in- gest and transform into soluble peptone from soluble, after treatment in alcohol, is exposed two hundred and fifty to three hundred parts to the action of water; that part still remain- of meat. Its solubility in different fluids aling insoluble is boiled in concentrated sulphu- lows it to be used in a great many pharmaceuric acid, for the conversion of starch, etc., into tical forms; and, being a vegetable juice, it can dextro-glucose. Boiling the residue from this be preserved with more stability than animal fertreatment with sodic hydrate gives an extract ments, and can be kept indefinitely when dry. containing albuminous matter, modifications of REPORT ON PHOTOMETRIC STANDARDS.—The pectic acid, Fremy's “cutose,” coloring, humus, committee appointed by the British Board of and decomposition products. The crude fiber Trade to examine and report upon the different from this process, treated with chlorinated soda, standards of photometric measurement which bleached, and dried, leaves a residue of cellu- have been proposed for adoption, as well as upon lose. Treatment with benzole, 80 per cent the standard now used for testing the illuminatalcohol, and water, removes from nearly all ing power of coal-gas, bave made a report replants the constituents of greatest chemical commending the standard air-gas flame of Mr. G. and medicinal interest. In analyses of food Vernon Harcourt as the most exact and trustmaterials the compounds extracted by dilute worthy. This flame is produced by burning acids and alkalies have great value.

a mixture of air with that portion of AmeriA New DIGESTIVE AGENT.-In a paper be can petroleum which, after repeated rectificafore the French Academy of Sciences, M. Wurtz tions, distills at a temperature of 50° C. or 122° has drawn attention to the great chemical and Fahr. The portion is almost entirely comtherapeutical value of a substance called pa- posed of pentane, and is used in the proporpaine, which possesses the property of exciting tion of one volume of pentane at 60° Fahr. to the digestive function. It is derived from the 576 volumes of air. The flame is brought to juice of the common papaw-tree (Carica papa a height of two and a half inches with a burnya), which belongs to the family of the Cucur er a quarter of an inch in diameter. The light bitaceæ, or gourds. The milky juice which con- is quite uniform, the extreme difference obtained tains the papaine is slightly bitter and styptic, by two observers in nineteen observations befree from tartness, but with a weak acid reac- ing 0-3 of a candle, or 1.8 per cent. The comtion, and is so highly charged with albumen mittee found candles very objectionable as standthat Vauquelin compared it to blood deprived ards, and subject to a maximum variation in of its coloring matter. It flows from incisions 115 determinations of 22:7 per cent between made in the bark and the green fruits, and is two pairs of candles. Messrs. Keates and Sugg's immediately bottled and sent to market, either plan for burning sperm-oil with a two-inch pure or with the addition of ten or twelve per fame from a circular wick was found subject cent of alcohol to prevent fermentation. If to sudden variations; and Mr. Methven's syspure, it becomes coagulated; if mixed with tem of allowing only a particular part of a alcohol, it remains liquid, and, after standing, three-inch coal-gas flame to pass to the phoseparates into a clear liquid and a white pre- tometer was not considered sufficiently exact cipitate, composed in great part of albumen, for the work required of it.

COLOROMETRIC ESTIMATION OF CARBON IN fessor Eggertz, did not perceptibly affect the IRON.—The great extension which has taken color. place in the applications of steel has made it A New VEGETABLE COLORING PRINCIPLE. desirable to obtain tests for the presence of car- Messrs. S. P. Sadtler and W. L. Rowland have bon of a more minute degree of exactness than analyzed a new vegetable coloring matter has heretofore been deemed sufficient. Profes- found in the West-African wood called bethsor Eggertz has described, in the “Jern Kon- a-barra, a wood which is much valued for its torets Annalen," a method of colorometric esti- extreme toughness and its capability of receivmation which is applicable to cases in which an ing a high polish. The wood is compact, very exactness of 0.01 per cent is wanted. The basis heavy, and of nearly the color of black-walnut. of his process is the solution of ferric hydrate On close examination the interstices of the in nitric acid, to which a volume of water equal fibers are seen to be filled with a yellow, crysto that of the acid is added; when the quan- talline powder. In this respect the beth-atity of acid used is commensurate with the barra differs from logwood, barwood, camproportion of carbon in the iron, the yellow, wood, and red sandal-wood, with which it was green color of the solution is cleared on adding compared, in which the color is uniformly disan equal volume of water. Care must be taken seminated, and the fiber appears as if it had that no chlorine is present, for the slightest been soaked in a solution of corresponding trace of that substance gives a yellowish tint. color. The solution of the coloring matter The quantity of nitric acid required for solu- obtained by extracting from the sawdust or tion is regulated to a certain degree by the raspings was treated for precipitation with supposed amount of carbon in the iron. For a acetic acid, and the pure substance was obsolution with a lower amount of carbon than tained by successive crystallizations from the 0-25 per cent, 2.5 c. c. of nitric acid should be alcoholic solution of the precipitate. The maused for 0.1 gramme of iron; with carbon of 0-3 terial thus gotten is a tasteless, yellow comper cent, 3 c. C.; with carbon of 0.5 per cent, 3.5 pound, apparently crystallizing in scales and c. c.; and for carbon of 0.8 per cent, 4 c. c. of needles, which are found under the microscope acid. When the ainount of carbon is altogether to be made up of a series of flat prisms, joined unknown, begin with 2.5 c. c. of nitric acid, and laterally. The crystals are unchanged in dry afterward add more as soon as the color of the or moist air, insoluble in cold water, very solution or the amount of separated carbon slightly soluble in hot water, but readily solushows that more acid is required. Too little ble in alcohol and ether; they dissolve with a acid gives too deep a shade, while excess of deep claret-red color in the presence of even a acid may be remedied by adding more water. trace of alkali or alkaline carbonate, and melt The iron to be tested should be finely divided at 135° C. Analysis gives a composition for by filing, boring, planing, or crushing. The the material dried at 125° C. which is represolution should be made at 80° C., with shak- sented by the formula 0,8H,,Os, or possibly ing of the tube. It is often more convenient 02,H2,0s, and for that dried at 100° C., C28 to put the tube in boiling water; and speed H2,06 +31,0. The beth-a-barra presents a can be gained at the expense of having a red- similarity in many of its reactions leading dish-yellow film to deal with, by gently boils to the suspicion of a relationship with chrysoing the mixture. Special normal solutions, phanic acid and chrysarobin. for comparison, are prepared in the same man ACTION OF SEA-WATER ON CAST-IRON.-Proner and graduated by successive dilutions from fessor A. Liversidge, of the University of Sydthe normal, which represents 0.10 per cent of ney, has made a study of the action of sea-water carbon per c. c. of 0.1 gramme of iron, and may on cast-iron in the case of the screw of the steambe used for iron with 0.8 per cent and higher dredge Hunter, which became so rotten that it of carbon, down to the to normal which rep- had to be removed. Even on the most cursory resents 0·005 per cent of carbon, and is used examination the specimen was seen to differ for iron with from 0.04 to 0.08 per cent, or the entirely from the original cast-iron, except in lowest amount of carbon found. The distribu- its shape, which remained unchanged. The tion of the light in the room should be consid- material was so altered in composition that it ered in applying the test, and it should be ob- might be safely described as a pseudomorph, served that a tube held on the right is gener- since it was almost entirely made up of oxide ally a little weaker in color than one held on of iron and particles of graphite. It was quite the left. The presence of manganese in the sectile, being readily cut with a knife. The iron communicates a brown color, which is powder under the microscope presented a mixtchanged by heating to 100° C. to a weak red- ure of brilliant scales of graphite with brownviolet; chromium gives a grayish blue; vana- colored oxide of iron and a few widely scattered dium, a weak yellow; nickel, a green—all of minute particles of metallic iron. The exterwbich colors vanish under a greater or less di- nal part of the specimen was of a dull-gray lution with water. Cobalt gives a red color color, while within it was rusty brown, with which can not be regarded as absent till dark bands following more or less closely the the dilution has extended to 40 c. C. Phos- outer contour lines. The specific gravity was phorus, sulphur, copper, silicon, in the pro- found to be only 1.63. Phosphorus appeared portions in which they were tested by Pro- to have been completely eliminated by the

VOL. XXI.-7 A

action which had gone on, and the amount of air, especially when exposed to sunlight. If of sulphur was quite small. Several notices air is excluded it will remain unchanged for a of a similar transformation of cast-iron into long time. It is soluble in all proportions in graphite occur in the annals of chemistry, the water, alcohol, and ether, yielding colorless oldest one dating as far back as 1740. Wrought solutions, and produces a greasy stain on paper, or malleable iron does not appear to be subject which disappears after a time. It is a little to it. The plumbaginous masses thus formed heavier than water, is volatile at ordinary temfrequently but not invariably become red hot peratures, giving a vapor which forms a dense and spontaneously inflammable on exposure to fog with hydrochloric acid, irritates the mathe air. The transformation is attributable to cous membranes very much, and induces viothe local galvanic action set up between the lent headaches in those working with it. Its diffused scales of graphite, films of slag, or taste is acid and pungent, and very persistent; other foreign matter contained in the iron. its smell when fresh is very like that of nicoThe coating of plumbago and rust is negative tine, but after it has become darkened is more to the metal, and hence if left on assists in like that of pyridine. It neutralizes acids comfurther corrosion; but the rate of corrosion, pletely. Its composition is represented by the according to the observations of Mr. Robert formula C.H.N.. Mallet, appears as a decreasing one when the CULTIVATION OF NITRIO FERMENTS.-Mr. R.. coating first formed is removed prior to a sec- Warington has communicated some prelimiond immersion. When cast-iron is exposed to nary results of a course of experiments he has the combined action of fresh water and sea- been making on the conditions in fermentation water, the action is said to be much more which respectively determine the formation of rapid, for the heavier sea-water below, and nitric and nitrous acid. When a small quanthe lighter fresh water above, with the iron, tity of fresh soil is employed to seed solutions form a voltaic pile having two liquids and one of chloride of ammonium supplied with nutrisolid.

tive ingredients, a pure, or nearly pure, nitric A New MINERAL, BEEGERITE.-Mr. George fermentation is obtained if the solution is sufA. König has described and analyzed a new ficiently shallow and dilute, and the temperamineral from the Baltic lode of the Geneva ture low. Under such circumstances only a Mining Company, Park County, Colorado, to trace of nitrous acid is formed, and this changes which he has given the name of beegerite. into nitric acid before the conclusion of the The specimen on which the investigation was action. If the solutions employed are much made was composed of quartz, about one half, more concentrated, or the temperature is conand the new mineral in the two conditions of siderably raised, large quantities of nitrous acid a light gray mass, and of crystals showing are produced. In all cases in which soil has a darker gray color but exhibiting a very been used as seed, the nitrous acid exists only strong metallic luster, which were chemically temporarily in the solution, the final product of identical with the gray mass. Beegerite forms the fermentation being always nitric acid. Soil minute crystals of orthorhombic habit; has a added to a solution of nitrite of potassium, supspecific gravity of 7.273; acts before the blow- plied with nutritive ingredients, readily converts pipe like a mixture of galenite and bismuthite, the nitrite into nitrate. When solutions which with a small quantity of copper, and decrepi- have been seeded with soil and have undergone tates; and is dissolved by concentrated hydro- the nitric fermentation are themselves employed chloric acid, slowly in the cold, but rapidly in as seed for new solutions of ammonia, the final the heated acid. The analyses gave it a com- result as before is nitric acid, provided the soposition represented by the formula, Pbe Bilution used as seed is only a few months old. S, = 6 PbS+ BizSs, with some copper. The With older solutions the result of the fermencompound exhibits properties nearly coinciding tation is apparently only nitrous acid, which with those of galesite, and is qualitatively re- does not further change into nitric acid, except lated with the two species, cosalite and schir- when, as sometimes occurs, a white organism, merite.

a bacterium, after a considerable time, appears Tue ALKALOID OF PITURIE.—Professor Liver- on the surface of the liquid, and spreads, under sidge, of Sydney, New Sonth Wales, has ex- favorable circumstances, to cover it. When a tracted the alkaloid principle of piturie, a solution which has undergone the nitrous fervegetable substance obtained from a species of mentation is used as seed, it again produces a Duboisia, of the order Solanacea, which is purely nitrous fermentation. These results acchewed by the Australian natives, and exerts cord with the fact noticed by Pasteur, that the an action similar to that of tobacco. Baron energy of infectious organisms may be reduced von Mueller and M. A. Ladenburg had pre- by cultivation. The nitrifying ferment appears, viously experimented with the alkaloid, but then, to exist in the three conditions of the their accounts of it do not agree. As prepared nitric ferment of the soil, producing nitrates; by Professor Liversidge, by distillation of the the altered ferment producing nitrites; and the plant with caustic soda, solution in ether, and surface organism, which changes nitrites into removal of the ether by distillation, the alka- nitrates. loid, piturine, is at first clear and colorless, but RELATIONS OF BACTERIA AND VARIOUS GASES. becomes yellow and finally brown with access - Mr. F. Hatton has made some experiments to

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