108 Mr. F. C. Calvert on the Adultei'atiQn of Oils. 



If a fibrous mass is formed. If a fluid mass is formed. 



I • \ I * \ 



Animal. Vegetable. Fish. Animal, Vegetable. 



Neat's- \_..j„ Gallipoli.."! Sperm. Lard. Olive \ „!,;*„ 



foot Z"""^- India nut.. White. Seal. Pale raneseed j-wmte. 



Castor J Cod liver. Linseed yellowish. 



Freneh nut. . red. Poppy (I'ght) "| 



Hempseed {I'f^^^.^, Sesame {^-"Jj;.-)-^- 



Having given in a previous paragraph some of the most useful 

 reactions contained in this table, I shall simply call attention to 

 the following mixtures : — ncat'sfoot with rape, gallipoli with 

 poppjf, castor with poppy, hempseed with linseed, sperm with 

 French nut, and gallipoli with French nut. It is also necessary 

 here to mention, that the brown liquor on which the semi-sapo- 

 nified mass of sesame swims is a very delicate and characteristic 

 reaction. 



Phosphoric Acid. — One vol. of syrupy trihydrated phosphoric 

 acid was agitated with five vols, of oil and gave the following- 

 results : — 



Not coloured. Coloured. 



Animal. Vegetable. Fish. Vegetable. 



Lard. India nut. Sperm . . "1 j ,. Olive (slight) "l 



Neat'sfoot. Pale rapeseed. Seal.... \ ^ Gallipoli (slight) l„„„„ 



Poppy. CodliverJ ^'^^- Hempseed >green. 



Sesame. Linseed (brown yellow) J 



Castor. French nut brown yellow. 



The only reaction to be noticed is the dark red colour rapidly 

 becoming black, which phosphoric acid imparts exclusively to 

 the fish oils, as it enables us to detect one part of these oils in 

 1000 parts of any other animal or vegetable oil ; and even at 

 this great degree of dilution, a distinct coloration is communi- 

 cated to the mixture. 



Mixture of Bulphuric and Nitric Acids. 



The results given in the following table are obtained on agi- 

 tating one vol. of a mixture of equal volumes of sulphuric acid of 

 spec. grav. 1/845, and nitric acid of spec. grav. 1"330, with 

 five vols, of oil and allowing the whole to stand two minutes : — 



If coloured. 



, _ A . ^ 



Fish. Animal. Vegetable. 



Sperm . . ") Lard \, Gallipoli "1. , 



Seal.... Uark brown. Neat'sfoot (dark) /"'°""' Pale rapeseed ^ , 



CodUverJ French nut /brown. 



Sesame (becoming intense"! 



Hempseed (becoming black) f e'^een. 

 Linseed (becoming black) . . J 



Olive (orange) slight 'Iwiin^ 



Poppy (slight) J ye"°''' 



Indian nut (orange) slight . . white. 

 Castor {""rcT''^" 



