Declmber 28, 1899] 



NATURE 



215 



i.eld, which may prol;abIy depend on the circumstances of the 

 licounter when the molecule of salt is broken up, and so some 

 molecules may be broken up without being charged ; while 

 there is no reason to suppose that the absorption by a molecule 

 would be altered by its being charged with electricity. The 

 absorptions which are intensified by concentration and also by 

 heat must be ascribed to the condition of the molecules during 

 encounters, which will be more frequent in more concentrated 

 as well as in hotter solutions. The expansion of 

 certain bands with increased concentration by the nitrate, 

 must be ascribed to encounters of molecules derived from the 

 metal with those derived from the acid, which are much more 

 massive than the molecules of water and also than those de- 

 rived from the chloride. During such encounters the absorbent 

 molecules will be as it were loaded by the influence of the 

 other molecules. This view seems confirmed by the influence 

 which other solvents and other acids have on the absorptions. 

 Didymium chloride in alcohol gives the same bands as the 

 aqueous solution, but generally more diffuse and more or less 

 shifted a little towards the red. The same solution acidified 

 with hydrochloric acid exaggerates greatly these modifications, 

 almost washing out the more refrangible bands and breaking up 

 the very strong band in the yellow into several separate bands. 

 Glycerol as solvent gives modifications similar to, but more 

 strongly marked than, those of alcohol. The acetate in acetic 

 acid and the maleate in water gives similar but much less 

 marked modifications. The tartrate and the citrate in am- 

 moniacal solution also give similar modifications. The borate 

 in solid glass of borax also gives bands which are unmistakably 

 modifications of those produced by the aqueous solution. All 

 these modifications seem to be of the same character, though of 

 greater intensity, than the differences between the bands given 

 by nitrate and chloride, and may be attributed to the influence 

 of the comparatively complicated influences of the various 

 molecules during the times of encounter. In such cases as the 

 acid alcoholic solutions there will certainly be at least four chemi- 

 cal compounds mixed in the solvent, which may well produce a 

 complicated modification of the bands without destroying their 

 identity. — "Researches in the Sugar Group," by H. Jackson. 

 A summary is given of the joint researches of Mr. H. J. H. 

 Fenton and the author, which may be conveniently divided into 

 two parts. (o) Oxidation of the more common polyhydric 

 alcohols. The remarkable part which iron plays as a carrier of 

 oxygen was first pointed out by Mr. Fenton in the case of 

 tartaric acid, and has since been extended by him to other 

 hydroxy- compounds. An aqueous solution of the following 

 polyhydric alcohols, glycol, glycerine, erythrite, dulcite, nian- 

 nite and sorbite, was taken in turn, and after adding a small 

 quantity of ferrous salt to each, hydrogen peroxide was added : 

 in all cases a large evolution of heat took place. The oxidation 

 products in the case of glycol, glycerine and erythrite quickly 

 reduce Fehling's solution in the cold and restore the colour to 

 an alcoholic solution of magenta, which has been decolourised 

 by sulphur dioxide : on treatment with phenyl hydrazine acetate, 

 osazones were obtained which, on analysis, were found to 

 correspond respectively to glycolic aldehyde or diose, glyceric- 

 aldehyde or triose, and erythrose or tetrose. The oxidation 

 compounds of dulcite, mannite and sorbite do not reduce Fehling's 

 solution in cold, but quickly on warming ; they do not give the 

 "magenta" test; facts which serve to distinguish the hexoses 

 from the simpler members of the sugar group. On treatment 

 with phenyl hydrazine acetate there was obtained from dulcite 

 the osazone of inactive galactose, from mannite the hydrazone 

 of mannose, and from sorbite an osazone identical with gluco- 

 sazone. If an aqueous solution of glycol, glycerine or erythrite, 

 to which a very small quantity of ferrous salt has been added, 

 be exposed for a little time to the action of sunlight in the pre- 

 sence of atmospheric oxygen, it can be shown on examination 

 that a certain amount of the sugar has been formed. These 

 experiments may perhaps give a little support to the theory that 

 iron, which occurs in hasmoglobin and is associated so intimately 

 with chlorophyll, may act as a carrier of atmospheric oxygen. 

 (3) Isolation of diose in a crystalline state and its condensation 

 to a hexose. When dioxymaleic acid, suspended in water, is 

 distilled on the water bath under very diminished pressure and 

 the distillate evaporated to small bulk in a vacuum desiccator, a 

 syrup is left which on standing crystallises out in flat plates of 

 the oblique system. On analysis and examination it is shown 

 to be crystalline diose. A determination of its molecular weight 



NO. 1574, VOL. 61] 



by the depression of the freezing point of water shows the crystal 

 to be bimolecular, but on standing and taking frequent determin- 

 ations the molecular weight gradually becomes normal and corre- 

 sponds to the single formula C2H4OJ, and then remains quite 

 constant. If a dilute aqueous solution of diose be treated 

 with a I per cent, solution of soda at the ordinary temperature 

 it quickly turns yellow and finally brown. After standing a 

 few hours it no longer reduces Fehling's solution in the cold, 

 but readily on warming : it no longer gives the " magenta " 

 test : in fact, it has lost all the properties of diose and assumed 

 those of a true hexose. This is confirmed on examining the 

 osazone, which corresponds to a normal hexosazone. The 

 melting point and action towards solvents of the osazone prove 

 its identity with & acrosazone, which Fischer and Tafel isolated 

 from the condensation product of glycerose. — On a new mineral 

 by A. Hutchinson. A colourless transparent crystal of the new 

 mineral was found on a specimen of Axinite from Cornwall in 

 the Came collection recently acquired by the University. The 

 crystallographic and optical constants of the crystal prove it to 

 belong to the Prismatic system. The results of a quantitative 

 chemical analysis agree well with the formula CaSn(Si03)3.2H,0. 

 The mineral has been named Stokesite in honour of Sir George 

 Gabriel Stokes. — On the condition that five lines in space of 

 four dimensions should lie on a quadric, by H. W. Richmond. 

 In order that five straight lines situated in a space of four 

 dimensions should lie on a surface of the second order a con- 

 dition must be satisfied. It is here pointed out that the known 

 properties of quadrics in space of five dimensions suggest a 

 simple mode of expressing the necessary condition. 



St. Louis. 

 Academy of Science, December 4. — Dr. Edward H. 

 Keiser described some derivatives of acetylene, exhibiting 

 specimens of the new liquid acetylene iodide discovered by him 

 in January, 1899. He described the methods of making the 

 compounds, and gave an account of its chief physical and 

 chemical properties. The liquid acetylene di-iodide solidifies at 

 -21° C. and boils at 185°. It has the percentage composition 

 and molecular weight represented by the formula C2H2I2, and 

 is isomeric with the well-known solid acetylene di-iodide. The 

 speaker announced the discovery of a new method of makiiig 

 the liquid acetylene di-iodide, namely, by heating the solid 

 compound to 260° in a sealed tube. The solid compound is 

 thereby partially converted into the liquid compound. Simi- 

 larly, if the pure liquid di-iodide be heated to 260° in a sealed 

 tube, on cooling down the liquid will be found to have been 

 partially converted into the solid compound. All the facts 

 known indicate that these two iodides of acetylene are stereo- 

 isomers, and that their configuration must be represented by 

 the stereometric formulas 



Hs 



v" 



"\c/^ 



and 



i/^'Xh 



Since Dr. Keiser has found that the solid acetylene di-iodide can 

 be converted into fumaric acid, it would follow that the first 

 of the two formulas would represent the solid acetylene di-iodide 

 and the second one the liquid di-iodide. Further experiments 

 upon these compounds are under way, and the attempt will 

 be made to convert the liquid di-iodide into maleic acid.— Dr. 

 K. Bremer demonstrated some tests for glucose by means of 

 aniline dyes, showing that nearly all of the " alkaline " aniline 

 dyes, when rendered basic by the addition of sodium hydrate, 

 become decolourised, or have their colour greatly modified, on 

 heating, in case glucose is present. The reactions shown were 

 especially pretty in the case of methylene blue and safranine. — 

 Prof. Nipher announced that he had nearly completed prepar- 

 ations for the measurement of wind pressures on the sides of the 

 main building Of Washington University. The pressures are to 

 be measured at various points along the west end of the build- 

 ing, having a width of about 50 feet, and along the north front, 

 which is something over 200 feet in length. Simultaneous 

 measurements of wind pressure, and wind velocity and direction 

 will be made. The method used is that tested by him on the 

 trains of the Illinois Central Railroad during the summer of 



