8 Scicnfific Prncije<li)i(js, Hoj/al Duhlin Societn . 



with the volumetric method with Fehling solution may be made as follows : — 

 As usually made up, 100 c.c. of Fehling solution is decolourized by 0'5 gm. 

 dextrose, or slightly less sucrose. Eeading to 0'2 c.c., the probable error 

 is 0001 gm. 



With the cryoscopic method, readings of temperature may be obtained 

 with an error of + 0-003°; 0'01° corresponds to 0'2 per cent, of sucrose. 

 Only 2-5 c.c. is necessary for the determination, so that the probable error 

 is 0-0016 gm. 



Eefeeences. 



1. Davi.s, W.A.— Journ. Soc. Chem. Industry, Feb., 1916. 



2. Dixon, H. H.— A Thermo-electric Method of Cryoscopy. Proc. Eoy. 



Dublin Soc, 1911, vol. xii, p. 49. 



3. Dixon, H. H., and Atkins, W. R. G. — Osmotic Pressures in Plants. 



i. Methods of Extracting Sap. Proc. Eoy. Dublin Soc, 1913, 

 vol. xiii, p. 422. 



4. Hambueger, H. J.— Osmotischer Druck und lonenlehre. Wiesbaden, 



1902. 



