CHEMISTRY. (NEW SUBSTANCES.) 



113 



first iodosulphide, and the reaction is accom- 

 panied by the liberation of fumes of hydriodic 

 acid. They take fire upon warming in the air, 

 disseminating the odor of sulphur dioxide and 

 the violet vapor of iodine. Water dissolves 

 them rapidly, producing trisulphide of phos- 

 phorus and hydriodic and phosphoric acids, 

 and sulphureted hydrogen is subsequently 

 evolved owing to the decomposition of the tri- 

 sulphide. The third iodosulphide was obtained 

 by reacting with excess of tri-iodide of phos- 

 phorus upon the trisulphide. It is deposited 

 from carbon bisulphide in deep-red crystals, is 

 very rapidly decomposed by moist air, and its 

 composition is P 2 SI 4 . It thus appears that io- 

 dine is capable of replacing more or less of the 

 sulphur contained in the sulphides of phos- 

 phorus, although it does 'not succeed in totally 

 eliminating sulphur from its combination with 

 phosphorus. M. Ouvrard has also obtained sev- 

 eral new halogen derivatives of the sulphides of 

 arsenic and antimony. 



A new iodine compound, in which iodine is 

 the central, predominating, or grouping element, 

 has been formed by Prof. Victor Meyer and Dr. 

 Hartmann, in which that element acts in a triva- 

 lent capacity, like the nitrogen in ammonia. 

 The substance has further the novel character 

 for an iodine compound, of acting as a powerful 

 base, combining with acids to form well-defined 

 salts with elimination of water, precisely as when 

 a caustic alkali is neutralized by an acid. It is 

 derived from a still unisolated base similarly 

 constituted to hydroxylamine, iodine taking the 

 place of nitrogen. It is prepared by exposing 

 iodosobenzine to the action of sulphuric acid, 

 whereby the sulphate of the new base is formed. 

 The solution may be used advantageously to 

 prepare the insoluble halogen salts, when the 

 free base may be obtained from the precipitated 

 iodide by agitation with moist silver oxide; or 

 it may be obtained directly from the sulphate 

 by adding baryta water. The aqueous solution 

 reacts very strongly alkaline. The base can not 

 be readily obtained in the anhydrous condition, 

 as it concentrates to a thick gum. Analysis of 

 the iodide indicates that the empirical formula 

 of the salt is C 4 H 3 I, and its molecular formula 

 Ci 2 H 9 I 3 . The formula of the base itself must 

 consequently be C 1Q H 9 I 2 OH. The chloride, bro- 

 mide nitrate sulphate, acetate, periodide. and 

 several double salts are described. The salts of 

 the iodonium bases, as a rule, bear a remarkable 

 resemblance to those of lead, silver, and particu- 

 larly thallium. The free base absorbs carbon 

 dioxide with great avidity, forming a carbonate 

 of the base, which effervesces upon the addition 

 of a dilute acid. 



The physiological action of the chloride of the 

 base has been studied in detail by Dr. Gottlieb, 

 of the Heidelberg Pharmacological Institute. 

 The salt has been found to be very poisonous, 

 and its mode of action upon the animal muscles, 

 membranes, and nerves combines the character- 

 istics of the action of lead and thallium salts 

 with those of ammonia and the ammonium bases. 



The fluorides of the radicals propyl, isopropyl. 

 allyl, and acetyl. and the fluorine analogue of 

 chloroform, fluoroform, have been examined, 

 and are described by M. Moissan. Propyl flu- 

 oride may be obtained by reacting with the cor- 

 VOL. xxxiv. 8 A 



responding chloride, bromide, or iodide the 

 iodide being the most convenient upon anhy- 

 drous fluoride of silver. It is a colorless gas, 

 smelling like the analogous chloride, and burns 

 with a brilliant flame, giving rise to aqueous 

 vapor, carbon dioxide, and hydrofluoric acid. 

 It liquefies at 3 C. at the ordinary pressure to a 

 colorless mobile liquid which is without action 

 upon glass. Isopropyl fluoride and allyl fluoride 

 are prepared in a similar manner from" the corre- 

 sponding iodides. They are both gaseous sub- 

 stances capable of condensation to liquids by 

 reduction of temperature or augmentation of pres- 

 sure. A mixture of allyl .fluoride with four 

 times its volume of oxygen explodes with great 

 violence under the agency of an electric spark, 

 or when brought into contact with a flame. 



When free fluorine is allowed to escape into 

 chlorine an energetic reaction occurs, chlorine 

 is liberated, and" in a few moments an explosion 

 is produced, with copious formation of carbon 

 tetrafluoride and fluoroform (CHP 3 ). Fluoro- 

 form liquefies at C. under a pressure of twenty 

 atmospheres. It is incombustible, but imparts a 

 bluish-green color to a Bunsen flame when in- 

 jected into it. It is insoluble in water, and has 

 a feebler odor than that of chloroform, but simi- 

 lar to it. With free fluorine it forms hydro- 

 fluoric acid and gaseous carbon tetrafluoride. 



A series of compounds of sugar with mercap- 

 tans, the sulphur alcohols, similar in many re- 

 spects in nature to the glucosides formed by the 

 combination of the ordinary alcohols with the 

 sugars, are described by Prof. Emil Fischer. 

 They differ, however, from the glucosides of the 

 alcohols in constitution, for they contain two 

 equivalents of the sulphur alcohol to one equiv- 

 alent of the sugar ; hence they are more nearly 

 allied to the similarly constituted compounds of 

 mercaptans with ordinary aldehydes. The mem- 

 bers of the series fully described are the ethyl 

 mercaptals of grape sugar and of galactose, and 

 the amyl mercaptal of the former. In addition 

 to these, Prof. Fischer has isolated the ethyl mer- 

 captals of mannose, arabinose, rhamnose, and 

 aglucoheptose, and has qualitatively proved the 

 generality of the reaction for xylose, maltose, and 

 milk sugar. The compounds appear likely to 

 prove important, for they are so readily formed 

 that they will serve in many cases as valuable 

 aids in the identification of either the well-known 

 or the newly discovered sugars. 



Besides the true carbohydrates, such as starch, 

 sugar, etc., a class of bodies is recognized as oc- 

 curring more or less abundantly in most plant 

 tissues to which the name pentosans or pentose 

 carbohydrates has been given. They are soluble 

 in dilute alkalies, and are converted by the re- 

 action of dilute acids into sugarlike bodies which 

 respond to many of the reactions for the true 

 sugars or glucoses. The results of experiments 

 made by W. E. Stone to determine the digesti- 

 bility of these bodies show that they are to a 

 marked degree less digestible than the true car- 

 bohydrates, with which they have been indis- 

 criminately classified. 



A glucoside iridine exhibiting some remark- 

 able properties is described by MM. F. Tiemann 

 and G. De Laire, as obtained from the iris by 

 treating the alcoholic extract with a mixture of 

 acetone and chloroform of density 0*98. It crys- 



