396 
Journal of Agricultural Research 
Vol.XXVI, No. 9 
2.7 for the 20 slide. By looking at Figure 4 it is found that 1.1 mm., on 
the curve for the 5 slide, represents 23.4 mgm. per liter; 1.6, on the curve 
for the 10 slide, represents 24.8 mgm. per liter; and 2.7, on the curve for 
the 20 slide, represents 22.0 mgm. per liter; or, when averaged, they show 
that the solution under observation contained 23.4 mgm. of carotin per 
liter. 
Table VII .—Lovibond slide readings for a solution of carotin in ether 
Yellow Lovibond slide No. 
Date. 
Concentration of carotin in milligrams per liter. 
42. 0 
33- 6 
25.2 
16. 8 
8.4 
4.2 
c. 
Feb. i.. . 
Mm. 
0. 6 
Mm. 
0.8 
Mm. 
I. I 
Mm. 
1. 3 
Mm. 
2.7 
2. 7 
Mm. 
6 . 2 
Feb. 2... 
5 
0. 8 
0.9 
1.4 
4. 9 
Feb. 3... 
0. 6 
0.8 
I. I 
. 
i- 5 
2.9 
5 - 9 ' 
Feb.1... 
0. 9 
1. 2 
1. 6 
2-3 
4 - 5 
8. 1 
Feb. 2... 
1. 0 
1. 2 
i- 5 
2. 2 
5-2 
8. 6 
Feb. 3... 
1. 0 
1. 2 
1. 6 
2.3 
4. 4 
8. 8 
Feb. i... 
1. 6 
1.8 
2. 2 
3-2 
7.8 
14. 0 
Feb. 2.. . 
i- 5 
1.9 
2- 5 
3-4 
6.9 
12.3 
Feb. 3... 
i -5 
2. 0 
2. 7 
3-8 
7-3 
13. 6 
AVERAGE OP THE READINGS 
i 
o. 57 
t 1 
0. 8 1. 03 1. 40 
2. 76 
0. 96 
1. 2 ! 1. 56 2. 26 
4- 36 
i- 53 
1. 9 | 2. 46 | 3. 46 
7- 33 
Table VIII .—Lovibond slide readings for a solution of carotin in petroleum ether 
Yellow Lovibond slide No. 
Date. 
Concentration of carotin in milligrams per liter. 
42. 0 
33-6 
25.2 
16. 8 
8.4 
4.2 
Mm. 
Mm. 
Mm. 
Mm. 
Mm. 
Mm. 
Feb. I. . . 
O- 5 
O. 7 
I. I 
I. 2 
2.3 
6. 0 
Feb. 2. . . 
o- 5 
o. 7 : 
! I -° 
I. 4 
2. 5 
4. 9 
Feb. 3... 
o- 5 
0. 7 
!■ 5 
2. 9 
5 - 1 
Feb. 1.. . 
0. 7 
I. 0 
i- 5 
2. 2 
4.2 
9. 7 
Feb. 2... 
1. 0 
I. I 
i- 5 
2.3 
4 - 5 
8. 7 
Feb. 3.. . 
0.8 
I. I 
2.4 
4 - 5 
9.0 
Feb. 1. . . 
1. 2 
I- 5 
2. 1 
3 - 2 
6. 7 
r 5 ’ 5 
Feb. 2... 
1. 6 
1.8 
2. 6 
3 - 8 
7.0 
13.0 
Feb. 3.. . 
1.4 
1.9 
4. 2 
7-3 
i 3 - 5 
AVERAGE OP THE READINGS 
.1 
0. 50 I 0. 70 
0. 83 1. 06 
1.40 1.73 
I.05 
I. 50 
2-35 
I.36 
2. 30 
3- 73 
2. 56 
4. 40 
7. 00 
5- 33 
9- 1 3 - 
14. 00 
