l 7 2 SCIENCE PROGRESS 



acid rosaniline, pararosaniline, and methylene blue can be 

 completely extracted from aqueous solution by means of ether, 

 safranine being extracted by means of diethylketone, while 

 glucosidic pigments are completely removed by one extraction 

 with the amylalcohol acetophenone mixture. 



A new method of estimating glucose in solution is described 

 by Willstatter and Schudel (Berichte, 191 8, 51, 780) ; the 

 solution whose strength is to be determined is mixed with 

 twice the amount of N/10 iodine solution necessary for the 

 oxidation of the glucose to gluconic acid according to the 

 equation 



CeHjsOe + 3 NaOH + 1 8 = 2 NaI + 2 H 2 + CH 2 OH(CHOH) 4 COONa 



and decinormal caustic soda is then added. After some time 

 the solution is acidified with sulphuric acid and the excess of 

 iodine is titrated. The error is less than o'i per cent, for 

 solutions containing 1 per cent, of sugar, and less than 

 1 '5 per cent, for those containing about o*i per cent. Ketoses 

 and cane sugar are not affected by the reaction, and the 

 method may consequently be used for determining glucose 

 in admixture with these substances. 



Harden and de Zilwa (Biochem. J. 191 8, 12, 93) have pub- 

 lished a paper entitled " Differential Behaviour of Antineuritic 

 and Antiscorbutic Factors towards Adsorbents." They find 

 that the antineuritic substance contained in autolysed yeast is 

 quantitatively adsorbed by Fuller's earth or dialysed iron. If 

 equal volumes of autolysed yeast containing antineuritic sub- 

 stance and lemon juice containing antiscorbutic substance are 

 treated with Fuller's earth the former is quantitatively removed, 

 whilst the antiscorbutic substance remains unchanged. At- 

 tempts to regenerate the antineuritic substance from its ad- 

 sorption complex have so far been unsuccessful. 



GEOLOGY. By G. W. Tyrrell, A.R.C.Sc, F.G.S., University, Glasgow. 



Physical Geology. — Jutson, J. T., Erosion and the Resulting 

 Land Forms in Sub-arid Western Australia, including the 

 Origin and Growth of the Dry Lakes, Geogr. Journ. Dec, 191 7, 



418-37. 



, On the Formation of " Natural Quarries " in Sub-arid 



Western Australia, Proc. Roy. Soc. Vict. 191 8, 30 (N.S.), pt. 2, 



159-64. 



