172 



THE ROYAL SOCIETY OF CANADA 



small scale in the laboratory. As will be pointed out later, they are 

 also peculiar in their ratios of the alkalinities of soluble and insoluble 

 ash. Table VII, which refers to more representative samples, shows 

 no material difference in the variability of the ratios. If anything, 

 the conductivity is more closely related to the total alkalinity than to 

 the separate alkalinities of either the soluble or the insoluble ash. 

 The range of variation of any of these ratios is somewhat wider than 

 that of the ratios of the alkalinities to one another. 



Conductivity Value of the Ash. 



Among the data of Tables III and VI is included for 19 syrups a 

 figure designated "Conductivity Value of the Ash," This was deter- 

 mined according to the following method: 5 grams of syrup are ashed 

 in a platinum dish. The ash is boiled with 30 c,c, water for two minutes, 

 filtered through a 7 cm, filter and washed with hot water to a volume 

 of nearly 50 c.c, (the residue is ignited and weighed as the insoluble ash). 

 The cooled filtrate is made up to exactly 50 c.c, and the conductivity 

 measured at 25°C, The solution is washed out of the conductivity cell 

 and titrated for alkalinity of soluble ash. 



This method departs from the conventional one for determination 

 of soluble and insoluble ash in maple products in using only 50 c.c, of 

 hot water on the ash of 5 grams of syrup, instead of 100 c.c. Possibly 

 it might be preferable to adhere to the conventional method of separat- 

 ing soluble and insoluble ash and to make the determination of conduc- 

 tivity value of ash in a volume of 100 c.c. instead of 50 c.c* 



To determine whether there is any material difference between 

 the results obtained with the two different quantities of wash water, 

 Mr, Scott has repeated the determinations upon syrups Nos. 2, 5 and 

 1 1 using 100 c,c, of wash water : The results obtained by the two methods 

 are compared below: 



* In the A. O. A. C. provisional incthod for saccluirine products in general, 

 only 60 c.c. of water are used. See U. S. Dept. Agr., Bureau of Chemistry, Bulle- 

 tin 107, p. 68 (1908). Hortvet followed this method. 



