2 ART. 1. — Y. OSAKA I 



quantity of water by warming. When it was cold, 5 c.c. of 2.5 

 normal liydroehloric acid were added and the solution was diluted 

 nearly to the mark. A small piece of camphor was then added 

 to the solution and the flask left in a thermostat at 25° over 

 night. On the next day water at 25° was added to the mark 

 and weighed. The two solutions thus prepared weighed : 



(a) 32.787, ib) 32.799; mean: 32.793. 



About 5 c.c. of the solution were taken out from each of 

 the solution into two weighed measuring flasks of 25 c.c. capacity 

 and weighed. About 4 c.c. of 2.5 norm, hydrochloric acid were 

 added to each of them and the solutions were diluted to about 

 20 c.c. The four diluted solutions thus prepared, together with 

 the two original solutions, were again left in the thermostat over 

 night. 



On the next day about 5 c.c. of the two original solutions 

 were taken out, each into two weighed measuring flasks of 

 25 c.c. capacity, and weighed. Tn order to prevent its further 

 inversion on dilution, 3.4 grams of sodium acetate were added to 

 the solutions taken out, which were then diluted to the mark. 

 The same amount of the salt was also introduced into each of 

 the solutions diluted the day previous to make them as nearly as 

 possible similar to those newly j^repared and then the solutions 

 were further diluted to the mark. It was ascertained by ex23eri- 

 ments that a small difference in the concentrations of hydro- 

 chloric acid exerts no remarkable influence on the optical rotation 

 of sugar solutions. 



The eight dilute solutions thus prepared were then subjected 

 to Polarimetrie observations, a polarisation apparatus after Landolt 

 being used with a Lippich's polariser. 



