39 
1914-15.] The Optical Eotation of Sugars. 
The polarimetric results (cf. figs. 11 and 12) are given in the following 
table, in which Grossmann and Bloch’s figures for mutarotation in pyridine 
solution are for red light. Their comparison between aqueous and 
pyridine solutions shows a much greater change in the latter than in the 
former solution. For water, [aJJd eight minutes after solution is —85°, and 
when constant —74°; whereas for pyridine, fifteen minutes after 
solution is —115°, and when constant —25°. 
Solvent 
Water.* 
Pyridine G. and B. 
Formamide. 
Graph 
X 
0 
+ 
Concentration 
i 
grams in 100 
> 9-9870. 
0-9997. 
2-2600. 
c.c. solution. 
Time. 
Time. 
r 1 20 
Lajred. 
Time. 
r 120 
6 min. 
- 104-02° 
15 min. 
-115-03° 
17 min. 
- 139-60° 
55 
102-29 
20 5, 
11003 
21 „ 
136-94 
74 55 
100-56 
30 „ 
105-03 
24 „ 
135-39 
8 55 
98-84 
45 „ 
101-03 
29 „ 
133-62 
9 5 , 
97-96 
60 „ 
98-02 
35 ,5 
I 130-97 
10 „ 
97-44 
90 „ 
93-02 
45 „ 
127-65 
15 „ 
93-80 
120 „ 
89-02 
57 „ 
123-89 
20 „ 
92-76 
150 „ 
85-02 
1 hr. 7 „ 
121-45 
25 „ 
92-42 
180 5, 
80-02 
1 5, 18 „ 
119-24 
35 „ 
92-09 
240 „ 
22 hrs. 
72-02 
1 „ 29 5, 
117-25 
4| hrs. 
92-09 
25-0 
1 5 , 40 „ 
115-93 
48 „ 
- 92-09 
48 „ 
- 25-0 
1 5 , 54 ,5 
114-38 
2 ,5 3 ,5 
113-49 
3 55 8 „ 
110-61 
3 ,5 42 5, 
109-51 
24 5, 1 
- 109-51 
K - 0-00839. 
Calc, initial 
[«]d = 
-151-76°. 
Extrapolated 
initial 
[«]»=- 151”. 
* Tollens and Parens (Annalen, 1890, 257, 166). 
