1894.] c^'tain IttMan Food Stuffs. 73 



or 250 c. 0. glycerin solution =25 c. c. — KM11O4 



10 



N 

 and 1 c. c. =rr KMnO^, =0*0046 gm, glycerin 



Total amount of glycerin =0*0046 X 25 gm.=0115 gm. 



whence percentage «= 11 03. 



N 

 But, 1 c.c. rrr KMa04 wheu titrated against pure oxalic acid was 



N 

 found to be equal to, 1 c. c. KMn04 (1-0-02) 



.*, percent, of glycerin (corrected) = n*03 (1—0*02) 



= 10*81. 

 2. 1'8877 gra. fat were saponified as above ; the heating was con= 

 tinned for 6 days on an average of 3| hours each day. 



The filtrate* ( = glycerin solution) was made up to 600 c. c. of which 

 50o. c. were oxidised to KO, &c. 



The CaO sol. was made up to 250c. c. of which 100c. c. required 

 N_ 

 10 



.*. 260C.O. CaO sol. =(1*7 x|)c. c. ^ KMnO^ 



N 

 or 50c. c. glyo. sol. =4'26c. c. — KMnO^ 



or 500 „ „ „ =»42*5 „ „ „ 

 whence percentage of glycerin = 1036 

 per cent, corrected =1036 (1-0*02) =10*16 

 Theoretical percentage of glycerin in mutton-fat, calculated as 

 tri-stearin= 1033. 



Determination op Glycerin in Niger-Seed Oil, 



1, 3" 165 gm. oil were treated with potash solution and asbestos, 

 &c., as in the case of mustard oil. 



The glycerin solution was made up to 250 c. c. of which 50 c. c. were 

 oxidised to 0, and the CaO sol. also made up to 250 c. c — 



_N 

 10 



1*7 o.c. T^KMnO^ 



50c. c. CaO sol. =3c. c. rr: KMnO^ 



* The filtrate in the above cases was very faintly milky. It waa therefore 

 surrounded by ice-cold water to solidify, if possible, minute traces of fatty acids 

 which might have remained in suspension. The opalescence, howevex', could not 

 be got rid of. On standing for 3 to 4 days the solution kept in a stoppered flask 

 became clear, but was at the same time the nidus of a kind of fungoid growth, 

 resembling flakes of cotton -wool, 

 J 11. 10 



