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VALERIC ACID, or VALERIANIC ACID, C4H9-CO2H, an organic acid belonging to the fatty acid series, which exists in four isomeric forms, one of which contains an asymmetric carbon atom and consequently occurs in two optically active modifications and one opticall ...

... a highly acrid poison. Aniline is a weak base and forms salts with the mineral acids. Aniline hydrochloride forms large colourless tables, which become greenish on exposure; it is the " aniline salt " of commerce. The sulphate forms beautiful white plates. Al ...

... -4)(OCH,)(CH:CH-CH,.) It also contains methyl chavicol, anisic aldehyde, anisic acid, and a terpene. Most of the oil of commerce, however, of which anethol is also the chief constituent , comes from Illidum verum (order Uagnoliaceae, sub-order W inter eae), in ...

... in alcohol and ether, but readily soluble in hot benzene. It unites with picric acid to form a picrate, C,4H« C,H, (NO,),-OH, which crystallizes in needles, melting at 138° C. On exposure to sunlight a solution of anthracene in benzene or xylrne deposits para- ...

... s treatment, the mixture is run into lead-lined vats and treated with sulphuric acid, steam is blown through the mixture in order to bring it to the boil, and the anthracene is rapidly oxidized to anthraquinone. When the oxidation is complete, the anthraquinon ...

... rdization has been effected in many instances, and a water solution of carbolic acid of a certain fixed strength is now taken as the standard with which other antiseptics are compared. The more important of those in use to-day are carbolic acid, the perchlorid ...

... ent group Ca(F, Cl, OH) takes the place of one hydrogen atom in orthophosphoric acid HjPO<. The formula is sometimes written in the form 3Caj(PO«)i-fCaFj. Mangan-apatite is a variety in which calcium is largely replaced by manganese (up to 10% MnO). Cerium, di ...

... ested that the organic nitrogen becomes oxidized into nitrous, then into nitric acid, which lowers the carbonate values. A great deal of reduction of this nitrogenous contamination can be effected by filtration, a method first introduced successfully at Hambur ...

... ay now bite as in ordinary etching for your darker tones, stopping out what the acid is not to operate upon, or you may use a brush charged with acid, perchloride of iron being a very good mordant for the purpose. After cleaning the plate, you proceed with the ...

... ontractile vacuole. It can develop vacuoles, or rather fine bubbles of carbonic acid gas in its cytoplasm, to float up to the surface of the water.

... empire is thus quite different in character from the Parthian kingdom of the Arsacids, which had no national and religious basis but leant towards Hellenism, and whose organization had always been very loose. Ardashir extirpated the whole race of the Arsacids, ...

... horoughly known. Beyond variable quantities of moisture* and traces of carbonic acid, hydrogen, ammonia, &c., the only constituents recognized were nitrogen and oxygen. The analysis of air was conducted by determining the amount of oxygen present and assuming ...

... s of the Upper Greensand are covered by the basaltic lavas of Tertiary age. The acid and basic plutonic rocks (gabbros and granophyres) of Tertiary time occur in Ardnamurchan. A striking geological feature of the county is the number of dolerite and basalt dyk ...

... forming the trioxide. It is easily oxidized by heating with concentrated nitric acid to arsenic acid, and with concentrated sulphuric acid to arsenic trioxide; dilute nitric acid only oxidizes it to arsenious acid. It burns in an atmosphere of chlorine forming ...

... s mentioned in Trogus, Prol. xlii. 5. ARTABANUS II. c. A.D. 10-40, son of an Arsacid princess (Tac. Ann. vi. 48), lived in the East among the Dahan nomads. He was raised to the throne by those Parthian grandees who would not acknowledge Vonones I., whom August ...

... lso on its low thermal conductivity and its partial resistance to the attack of acids: hence it is used for jacketing boilers and steam-pipes, and as a filtering medium for corrosive liquids. It has also come into use as an electric insulator. , It is made int ...

... 457) synthesized the asparagincs from the monomcthyl ester of inactive aspartic acid by heating it with .iliuholic ammonia. In this way a mixture of the two asparagincs was obtained, which were separated by picking out the hrmihedral crystals.

... vith the marsh-mallow and some other plants, it contains asparagine or aspartic acidamidc. The roots of asparagus were formerly used as an aperient medicine, and the fruits were likewise employed as a diuretic. Under the name of Prussian asparagus, the spikes ...

... . wide, and the city has a water-front of about 5 m. and a deep, spacious and placid harbour. By dredging and the construction of jetties the Federal government has since 1885 greatly improved the channel at the mouth of the river. The business portion of the ...

... lytical discussion of the movements of Jupiter's satellites (Miscellonta, Turin Acid. t. iv.); and in the same year expanded Euler's adumbrated method of the variation of parameters into a highly effective engine of pcrturbational research. It was especially a ...

... ade some sort of compact with that emperor and, in 414, he married his sister Placidia, who had been since the siege of Rome a captive in the camp of the Goths. The ex-emperor At talus danced at the marriage festival, which was celebrated with great pomp at Na ...

... in winter. Hydrogen dioxide occurs in a manner closely resembling ozone. Nitric acid and lower nitrogen oxides are present, being formed by electrical discharges, and by the oxidation of atmospheric ammonia by ozone. The amount of nitric acid varies from place ...

... alkaline springs of Carlsbad, M.iricnb.id, Kranzenstud and liilin; the alkaline acidulated waters of (iiesshutx-l, largely used as table waters; the iron springs of Marienbad, Franzcnsbad and of Pyrawarth in Lower ria: the bitter waters of I'ullna, Saidschitz ...

... re pyro-electric, and he mentions the tartrates of potash and soda and tartaric acid as exhibiting this property in a very strong degree. He also made many experiments with the tourmaline when cut into thin slices, and reduced to the finest powder, in which st ...

... enbach's Institutions Physiologicae (1817); Cases of the Hydrocyanic or Prussic Acid (1820); Lectures on Diseases of the Heart (1830); Principles and Practice of Medicine (1839); Human Physiology (1840); and Surgical Operations in the Mesmeric Stale without Pa ...

... of the plant required for the manufacture of such chemical products as alkali, acids and dyes, and for the working of a wide range of industrial processes. The last great new branch is electrical engineering, which touches on the older branches at so many poi ...

... ines on metal plates (see LINEENGRAVING), or by the corrosion of the lines with acid (see ETCHING), or by the roughening of a metal surface without actual lines (see MEZZOTINT), or by cutting a wood surface away so as to leave lines in relief (see WOOD-ENGRAVI ...

... stack. When closely packed, the supply of oxygen is limited; and the attendant acid fermentation brings about the decomposition of the carbohydrates present into acetic, butyric and lactic acids. This product is named "sour silage." If, on the other hand, the ...

... t upon the bowels. Its nauseous bitter taste may to some extent be concealed by acidifying the solution with dilute sulphuric acid, and in some cases where full doses have failed the repeated administration of small ones has proved effectual. For the manufactu ...

... ms rose-coloured salts and a rose-coloured oxide. The oxide dissolves slowly in acids; it is not reduced by hydrogen and is infusible. The salts show a characteristic absorption spectrum. See J. F. Bahrand R. Bunsen {Ann., 1866, 137, p. i); A. v. Welsbach (Mon ...

... s also known as erythrol, erythroglucin and phycite. It corresponds to tartaric acid, and, like this substance, it occurs in four stereo-isomeric forms. The internally compensated modification, z'-erythrite, corresponding to mesotartaric acid, occurs free in t ...

... produced by the ploughing of the burin, the copper is eaten away or corroded by acid. To prepare a plate for etching it is first covered with etchingground, a composition which resists acid. The qualities of a ground are to be so adhesive that it will not quit ...

... n or air is violently explosive. The making of ether by the action of sulphuric acid on alcohol was known in about the i3th century; and later Basil Valentine and Valerius Cordus described its preparation and properties. The name ether appears to have been app ...

... r as mixed ethers. They may be prepared by the action of concentrated sulphuric acid on the alcohols, alkyl sulphuric acids being first formed, which yield ethers on heating with alcohols. The process may be made a continuous one by running a thin stream of al ...

... CHLORIC ETHER, C2H,C1, a chemical compound prepared by passing dry hydrochloric acid gas into absolute alcohol. It is a colourless liquid with a sweetish burning taste and an agreeable odour. It is extremely volatile, boiling at 12-5° C. (54-5° F.), and is the ...

... gas. It is usually prepared by healing a mixture of ethyl alcohol and sulphuric acid. G. S. Newth (Jour. Chem. Soc., 1901, 79, p. 915) obtains a purer product by dropping ethyl alcohol into syrupy phosphoric acid (sp. gr. 1-75) warmed to 200° C., subsequently ...

... nt producer of sulphur. Among other mineral products may be mentioned the boric acid and statuary marble of Tuscany, the statuary marble of Greece, the asphalt of Switzerland, Italy, Germany and Austria-Hungary, the slates of Wales, Scotland and France, the ka ...

... mbe in 1904 obtained the pure salts by fractional crystallization of the nitric acid solution with magnesium nitrate in the presence of bismuth nitrate. The salts have a faint pink colour, and show a faint absorption spectrum; the spark spectrum is brilliant a ...

... of water of crystallization, the anhydrous form melting at 234-235" C. Nitrous acid converts it into malic acid,

... ions (saccharimetry). They are neutral to litmus and do not combine with dilute acids or bases; strong bases, such as lime and baryta, yield saccharates, whilst, under certain conditions, acids and acid anhydrides may yield esters. Sugars are also liable to fe ...